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1. X RAY TUB TEMPERATURE S Spectrace Instruments QuanX Technical Manual 3 5 Product Description Figure 3 3 Right side view The X ray tube and shroud provide the primary X ray beam used to illuminate the sample The X ray tube is air cooled and may operate at up to 50 watts The target material of the X ray tube determines certain characteristics of the tube s spectral output and is therefore selected based on the intended application of the instrument For most applications a Rhodium Rh target X ray tube is used The shroud is part of the tube cooling system discussed below The X ray tube fan is dedicated to tube cooling The fan and shroud form a closed loop independent temperature control system The fan speed varies based on the temperature of an external sensor which is bonded to the shroud surrounding the X ray tube The shroud is mechanically coupled to the tube with a heat conductive interface Therefore as the tube heats up during use the fan speed increases to provide additional cooling This system serves to lower the fan speed when cooling demand is low thereby reducing noise It also serves to maintain a more constant tube temperature which is desirable for analysis stability The warmed exhaust air is vented outside the cabinet to avoid increasing the internal ambient temperature The fan is mounted on rubber isolators to prevent vibration of the detector Figure 3 4 shows a top view of a LN QuanX with
2. 1 Select the TRAY ACCURACY test from the procedure menu and press SETUP or set up the following conditions Overall setup ACQUISITION PARAMETERS ANALYSIS TECHNIQUE Tube voltage 20kV Method Linear Tube current 0 06 mA 0 12 ECD Mode Run unknowns Filter used Pd medium Std file 300 Livetime 100 sec Preset count Ok Max energy 20keV Atmosphere Air Warmup Do Ssec SPECTRUM PROCESSING SAVE ON DISK Ref file no 300 Spectrum Elements of int Brass Intensities File number Results Ext program Spectrum processing setup SPECTRUM PROCESSING 1 BRASS GROSS ROI lt 7200 10080 EV gt Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 30 Count rate range setup AMP COUNT RATE MEDIUM Highlight ACQUISITION PARAMETERS and press RUN Answer 1 for the number of unknowns to run The dead time should be approximately 50 If not press ACQU MENU amp ACQU PAR and adjust the tube current After the acquisition is complete highlight SPECTRUM PROCESSING and press RUN Answer 1 for the number of samples to run Display the spectrum by pressing DISP SPEC then typing C to select the current spectrum Write down the value of the ROI gross counts displayed on the upper right corner of the screen Add one washer under each tray pad and repeat the previous steps do not change the tube current Continue adding washers one at a time and noting the gross counts The count va
3. Faulty ADC interface Verify by substitution replace if required Figure cable 36 Faulty ADC board Verify by substitution replace if required Procedure 9 3 4 Faulty pulse processor module Verify by substitution replace if required Procedure 9 3 2 Noise pickup See Resolution is poor Faulty power supply Measure and adjust per procedure Replace Procedure 7 4 if required If dead time is high with X rays on The X ray tube voltage or current Lower the kV and or mA settings and restart is set too high the acquisition Improper filter selected Select a thicker filter Improper pulse processor count Select a higher range rate range selected Faulty ADC interface Verify by substitution replace if required Figure cable Alternate test note D T while acquiring a 3 6 spectrum and then select the ACQ PARAMETERS menu If D T drops when this menu is displayed it usually indicates a faulty cable noise is generated when spectral data is transmitted in acq par menu the data transfer is halted X ray control board requires Verify with X ray control voltage and Procedure 7 20 adjustment or is faulty anode current entries in the GEN STAT board test screen Replace if required Procedure 7 7 board adjust Filter positioning mechanism is Verify by exiting and restarting QUANX faulty An error message will appear if the mechanism doesn t initialize properly See Filters do not position correctly A
4. 7 18 Stray Lines Scope and purpose To verify that the intensities of any instrument sourced contamination in the X ray spectrum are below specified limits This is accomplished by analyzing a sample known to contain only very light elements which the instrument cannot detect The test is broken into two portions Test II checks for stray lines in the 4 to 10 keV range Test III checks for stray lines in the 10 to 25 keV range Test equipment Delrin sample Test conditions Optional The diagnostic diskette contents has been installed and the QUANX program has the active directory set as C SPECTRAC QTESTLN or C SPECTRAC QTESTECD for an LN or ECD system respectively 7 18 1 Stray Lines II 25kV Procedure 1 Place the plastic scatter block in the chamber Use the single sample tray horseshoe removed if the sample is not a standard 1 25 diameter size 1 Select STRAY LINES II test from the procedure menu or set up an acquisition with the following conditions Overall setup ACQUISITION PARAMETERS ANALYSIS TECHNIQUE Tube voltage 25kV Method Peak ratios Tube current 0 02 mA 0 04 ECD Mode Run unknowns Filter used Pd medium Std file 600 Livetime 500 sec Preset count Ok Max energy 40 keV Atmosphere Air Warmup Osec SPECTRUM PROCESSING SAVE ON DISK Ref file no 600 Spectrum Elements of int Cu Fe W R1 R2 Intensities File number Results Ext program Spectrace Instruments QuanX Tec
5. The chamber board detected a failure in the primary sample chamber lid interlock switch Cause Random noise event Hardware failure or adjustment required Technical reference Program too big to fit in memory Remed Open the sample chamber lid for one second and close it start the acquisition If unsuccessful turn the power off and on start the acquisition See the troubleshooting chart in the next section See schematic 5919 0217 chamber control board signal LID OPEN and INTERLOCK DOS error message DOS is unable to allocate sufficient memory to execute the program Cause Attempting to execute QUANX from within another program or shell Attempting to execute a large external program from within QUANX Insufficient base memory lower 640k available DOS is not loaded into high memory Computer memory failure Remed Run QUANX directly from the DOS prompt Exit QUANX and run the external program directly from the DOS prompt Computer must have minimum 1meg RAM installed Remove any memory resident programs from memory before running QUANX DOS 6 0 or higher required Add HIMEM SYS and DOS HIGH commands in CONFIG SYS file See Section 5 5 2 Run PC diagnostics Replace CPU board or repair as required System failed to calibrate hardware problem The system was unable to complete energy calibration with a sufficiently small error within 30 minutes The criteria is a funct
6. Dependent on standards quality and concentration Expected is 0 5 to 5 0 relative Dependent on concentration and analysis time Expected is 0 5 to 5 0 Typically monthly Solids powders filtrates liquids and thin films Standard single sample tray holds 1 4 inch 32mm diameter sample cups or large irregular samples up to the chamber size Optional trays available for multiple samples sample spinning 47mm diameter samples fixed disk data storage media and wafers 809 geometry between X ray tube sample and detector Distance from sample to LN detector 33 0mm ECD detector 28 5mm X ray tube target 80 3mm Side window Bremsstrahlung Rh target 50 watt 127 micrometer 5 mil Be window air cooled Optional targets and window thickness available Voltage range 4 to 50 kV in 1kV increments Current range 0 1 98mA in 0 02mA increments Maximum 50 watt output 0 25 RSD over any 8 hour period Automated 8 position filter selection AI cellulose 2 Cu and 3 Pd filters are provided 1mm 3 5mm 6 8mm Automated control of air vacuum optional or helium optional Spectrace Instruments QuanX Technical Manual 3 13 X RAY SENSOR ECD MODEL Detector Window Cooling Preamplifier Battery X RAY SENSOR LN MODEL Detector Window Cooling Preamplifier SIGNAL PROCESSING SYSTEM Pulse Processor Analog to Digital Converter Data Memory ADC interface board P
7. Hardware failure Failed to download file to ADC Remed Check the COMI connection at the back of the computer Cycle the power off and on Resume operation Verify by checking the sample tray after turning on the power If it never turns or never stops this is the problem See the troubleshooting chart in the next section Turn off the power Unplug the power cord ECD systems only Reseat the board firmly See the troubleshooting chart in the next section Not able to write the file INIT5500 into the ADC module because the computer cannot communicate with the ADC This file contains the ADC operating instructions and is sent to the ADC every time QUANX is executed from DOS Cause Remed See the Cause and Remedy for the message ADC failed to respond Retry previous task or check hardware and reload program Failed to initialize filters The filter wheel mechanism failed to establish the home reference position therefore the X ray transmission filters cannot be positioned accurately Cause Chamber control board requires a logic reset Hardware failure Technical reference Remed Cycle the power off and on restart the QUANX program See the troubleshooting chart in the next section See schematic 5919 0217 chamber control board signal FHD filter home detect Spectrace Instruments QuanX Technical Manual 10 8 Troubleshooting INTERLOCK CIRCUIT FAILURE DETECTED SERVICE REQUIRED
8. Options Schematic 0110 0634 0110 0609 50500 02 5919 0194 5919 0196 5919 0207 Assembly 5101 0201 5101 0225 02 5101 0232 02 5101 0233 5101 0382 5101 0366 5101 0367 5101 0368 5101 0371 5101 0372 5101 0373 5101 0374 5101 0375 5101 0378 Assembly 8100 7402 8100 7409 8100 7410 8100 7415 8100 7416 8100 7426 8100 7428 8100 6207 5911 0223 5911 0128 5911 0128 5911 0221 5101 0237 5101 0317 01 5101 0322 02 5101 0369 5101 0370 5101 0376 8100 7450 8100 7451 8100 7452 Optional Equipment 11 5 Title Filament Cable Vacuum Sensor Cable X ray Power Supply Control Cable ADC Interface Data Acquisition Cable old ADC Interface Cable new Chamber Feedthru Cable Chamber Lid Cable Warning Light Cable AC Distribution Power Tray Cable DC Power Cable Voltage Current Board Power Cable 24V PS2 AC Power Cable Cable Harness X ray Supply Power Cable Title Spinner Drive Assembly Helium Flush Tray Drive Assembly Cooler Power Supply 20 Position Sample Tray Assembly ECD Support Tray LN Sensor Ion Pump Assembly Pre amp Board ECD 4 Terminal FET Pre amp Board ECD 3 Terminal FET Pre amp Board LN 3 Terminal FET Bias Supply Board ECD Version Bias Supply Board LN Version ECD Control Board QuanX Fan Cable Ion Pump High Voltage Cable ECD Control Cable ECD Power Cable AC Power Cable Ion Pump Power Cable R Theta 2 Table R Theta 2 Slide R Theta 2 Disk Holder and Weight Set Spect
9. Procedure 1 Place the sample in sample tray position 20 12 Start the QUANX program Press SETUP then SYS STAT on the main menu and TEST PROCS on the PHA status page Select the RESOLUTION MANGANESE COPPER test from the menu 12 Press SETUP to verify Tube voltage 18 kV Tube current 0 04 mA 0 08 ECD Filter Pd medium Livetime 45 sec Preset count 0 Max energy 10 keV Atmosphere Air Warmup 5 sec 12 Press SYS STAT COUNT RATE and select Low or desired range count rate range Press EXIT Note normally only the low range values are of interest 12 Press EXIT and answer the prompts as follows Number of measurements 15 Resolution standard Mn or Cu as appropriate 12 Press RUN to start the test Press ACQU MENU amp SYS STAT The FAST DISC RATE should be between 1000 and 1500 cps If it is not press EXIT and ACQU PARM and adjust the tube current DT will be about 22 on low The system performs the selected number of acquisitions After each one it prints the following Full width at half max FWHM Running average of FWHM Peak to background ratio at 1 keV Peak to background ratio at 5 keV Averages for the two ratios Value of peak centroid Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 22 12 Verify that the final average resolution values are equal to or less than LN ECD Low Medium High Low Medium High Mn 155 eV 175 eV 250 eV 175 eV 195 eV 270 eV Cu 175 eV 195 eV n s
10. Shorted LED segment on the display board Faulty chamber control board The display board requires adjustment Troubleshooting Bypass the top cover and enclosure cover interlock switches by pulling out on their actuator rods If all internal interlocks are closed both the INTERLOCK LED on the X ray control board and the INTERLOCK IN LED on the chamber control board should be on If they are on see the next cause If not check the tube detector and chamber lid switches and the tube filament cable jumper J5 4 amp 5 Verify and replace the board Explanation The X rays are not really on no power is leaving the chamber control board to power the X ray HV supply The INTEROUT voltage is low it should be approximately 24V Verify and replace the board Explanation The current through the chamber board resistor R112 is high Verify by removing the board and turning on the X rays 3 or 4 of the 8 segments will be on unusually bright The remaining segments will be on dim If so replace the board Verify and replace the board High current signal trips at R112 voltage of 2 5V Best to replace the board If not available adjust the display board pot to achieve 2 10V at the chamber control board resistor R112 Allow the light to run 10 minutes before making the adjustment Spectrace Instruments QuanX Technical Manual 10 35 0110 0632 5919 0217 interlock 5919 0217 confirm Procedure 9 3 1
11. temperature status Helium high flow status Interlock status Diagnostic Software Usage Respons e EExx AAO AAF ABO ABF ACO ACF AHO AHF AIO AIF APO APF Ax AFF AGO AGF AHO AHF AIO AIF AIX 8 6 Response Description Convert xx from ASCII to binary then Bit Item Bit 0 Bit 1 0 coolers ON OFF 1 heat sink OK HOT 2 ext cooler V OK HIGH 3 ion pump ON OFF 4 ion pump curr OK HIGH 5 ecdinstalled YES NO 6 amp 7not used ECD is installed ECD is not installed Cooler voltage is OK Cooler voltage is HIGH Coolers ON Coolers OFF Heat sink OK Heat sink HOT Ion pump current is OK Ion pump current is HIGH Ion pump is ON Ion pump is OFF Filter is at position x 1 Error in filter initialization LN level or ECD temperature is OK LN level is LOW or ECD temp is HIGH High flow valve is ON High flow valve is OFF Interlock CLOSED Interlock OPEN Interlock FAILED to open when the chamber lid was opened Spectrace Instruments QuanX Technical Manual 8 7 Comman d query QJ QK QL QM QN QP QQ QR QS QS QS QT Name Warning light ON sense X ray confirm signal actual hardware check ECD cooler control status see QEC also ROM ID rev Number of sample tray positions X ray control status see QK also Warning light current status Chamber vent status up to air valve Sample tray posi
12. 195 eV 215 eV n s n s not specified and that the low range manganese peak to background final average values are equal to or greater than LN ECD 1 KeV 5 KeV 1 KeV 5 KeV Mn 1200 550 1200 400 copper peak to background values are not specified Note The peak to background ratio is indicative of the detector alone The resolution FWHM is indicative of the detector and its electronics Spectrace Instruments QuanX Technical Manual 7 23 Test and Adjustment Procedures 7 12 Stability Scope and purpose To verify that the X ray generation and detection subsystems are functioning correctly Also to differentiate between problems arising in the two systems Test equipment Copper sample Test conditions Complete fully functional system Procedure 1 Place a copper sample in tray position 20 1 Press SETUP then SYS STAT on the main menu and TEST PROCS on the PHA status page Select the RESOLUTION AND STABILITY test from the menu 1 Press SETUP and enter the following conditions Tube voltage 35 kV Tube current 0 20 mA 0 40 ECD Filter Cu thin Livetime 300 sec Preset count 0 Max energy 20 keV Atmosphere Air Warmup 600 sec Or the test may be run at the conditions normally used for unknowns analysis 1 Press SYS STAT COUNT RATE and select Medium count rate range or the range used for unknowns analysis Press EXIT twice Enter 8041 for the energy of the line 1 Highlight RESOLUTION AND STABILITY
13. 4 11 ADC Interface Board The part number for this board is 5911 0181 for the original version non shielded cable or 5911 0224 for the newer version shielded cable The circuit for this board 1s shown in schematic 5919 0181 The board provides memory for storing the spectra that are being collected It also provides the communication path between the computer and the analyzer This board occupies one expansion slot in the computer Memory The data memory is organized as 4K by 24 bits three bytes Both the ADC and the computer can access this memory The ADC accesses it 16 bits at a time reading or writing to the two least significant bytes In the computer the contents of this data memory are mapped into its RAM space as a 16Kx8 block Starting at the beginning of this block the first three bytes of RAM correspond to the first 24 bit data memory word The fourth byte does not exist and reading it returns zeros This pattern is repeated for the entire block of RAM one byte at a time Since both the ADC and the computer can access the data memory a bus arbitration circuit is used to prevent them from accessing it at the same time When the ADC access the data memory it generates a memory request and then waits until it receives a grant from the arbitration circuit When the computer accesses the data memory the VO CHANNEL READY line goes low causing wait states to be generated until the arbitration circuit sets it high again Whichever has
14. A fully charged battery will support the ion pump for 72 hours however this battery is used during shipping so the instrument should be connected to an AC power source immediately upon receipt If ion pump power is lost the housing vacuum will begin to decrease and within 3 hours it can deteriorate to a level at which the ion pump will not function properly when power is reapplied Such a condition should be avoided since it can only be corrected by repair or replacement of the ECD assembly Liquid nitrogen maintenance The LN level must be maintained whether or not the system is in use The LN dewar should be filled upon receipt of the instrument and at regular intervals thereafter Although it is unusual the detector crystal can be damaged by frequent temperature cycling experienced when the dewar is allowed to reach room temperature between fillings In addition condensation forms inside the dewar as it is approaching room temperature If this water is not removed before filling the dewar with LN ice will form inside The ice can lead to performance problems and corrosion of the dewar interior Spectrace Instruments QuanX Technical Manual Installation 5 5 5 4 QuanX Setup This section describes the procedures required to complete the basic setup in preparation for functional and performance testing Conditions The installation site must meet the requirements detailed in Section 5 2 Site Preparation Required equipment Basic hand
15. EAO Vacuum pump is on ETF Chamber lid is not locked ELID Chamber lid is open EPO X rays are on ERX R Theta stage linear axis failed to establish home position ERY R Theta stage rotation axis failed to establish home position 8 3 5 General Usage Notes Inconsistent chamber atmosphere requests such as vacuum and vent on at the same time are corrected automatically by setting the vent valve to the appropriate state no error message Requesting vacuum and helium operation at the same time generates an error message The chamber lid must be closed before locking the latch if it is not an error message will result The latch should be locked before turning on the X rays and the X rays should be off before unlocking the latch If these are not executed manually the chamber board program will carry them out automatically no error message The interlock interrupt should be reenabled every time an interlock is broken The star messages RST amp INT may be sent by the board at any time they are not in response to a Q or C input Any number of C commands may be issued before the execute CX command is sent The operations will be carried out sequentially in a predetermined order Commands received which generate an error response will not be carried out but any prior commands issued are not disturbed Spectrace Instruments QuanX Technical Manual 8 11 Diagnostic Software 8 4 QUANX Service Mode The QUANX analysis program
16. J6 located on left side of the power supply tray This allows the tray to slide forward farther 1 Hlip up the radiation shield Slide the tray forward Free cables as required to allow about 1 3 of the tray to protrude 1 Unplug both white connectors from the power supply Spectrace Instruments QuanX Technical Manual l Component Replacement 9 8 Rotate the tray 90 degrees clockwise Remove the ground lug with two black wires from the top of the power supply Remove the two screws securing the power supply to the tray Remove the green yellow wire safety ground wire from the supply chassis Install the replacement supply by executing the previous steps in reverse order For easier access to the 5V adjustment control do not replace the X ray high voltage power supply yet Be sure to not pinch any wires behind the power supply tray when reinstalling it Turn on the power and measure between TB2 10 and gnd TB2 8 Adjust the pot located below TB2 to obtain 5 20V 0 05V Check the other voltages per Table 7 1 which is part of Procedure 7 4 Power Supply Test and Adjustment Install the X ray high voltage power supply and enclosure cover 9 4 3 PS2 24V Switching l 1 Rh 2 2 See Figure 7 3 for the location of this supply Turn off the instrument power Disconnect the instrument power cord Remove the four rear panel screws which hold the enclosure cover in place Remove the enclosure cover by grasping it on the bo
17. Procedure 9 3 1 10 34 Shorted X ray tube Faulty X ray high voltage power supply Faulty X ray control board Symptom The X ray warning light is on but the computer says it is off One of the 8 LED segments in the light is open causing 4 to go out The display board is shorting against the chamber lead shield The display board requires adjustment Faulty chamber control board Symptom The computer says an interlock is open Power supply is faulty or requires adjustment Troubleshooting Use TXCONFIG to set SERVICE MODE to YES Disconnect the HV cable from the X ray high voltage power supply not from the tube To prevent excessive tube filament heating also disconnect the X ray control board J5 and jumper pins 4 amp 5 on the board Turn on X rays 10kV or less if the X ray warning light comes on as normal the tube is the most likely problem if not see next cause It s possible the HV supply is the problem but only under load Replace one of the two to verify Use TXCONFIG to set SERVICE MODE to YES Unplug J4 from the X ray control board to eliminate the HV supply To prevent excessive tube filament heating also disconnect J5 and jumper pins 4 amp 5 on the board If the X ray warning light comes on as normal now replace the HV supply Use TXCONFIG to set SERVICE MODE to YES Unplug J2 and J3 from the board Use a paper clip to short the cable ends together J2 pin 1 orange and J3 pin
18. Remove the screw that secures the front of the power supply tray to the enclosure 1 Disconnect the two white in line connectors J5 amp J6 located on left side of the power supply tray This allows the tray to slide forward farther 1 Hlip up the radiation shield Slide the tray forward Free cables as required to allow about 1 3 of the tray to protrude 1 Remove the perforated metal shield from the tray assembly 1 Disconnect the power supply s AC connector a white in line connector labeled J1 located between PS3 and PS4 1 Rotate the tray 90 degrees clockwise Remove the screws securing the power supply to the tray 1 Remove the green yellow wire safety ground wire from the supply chassis 1 Install the replacement supply by executing the previous steps in reverse order Do not install the enclosure cover 1 Check or adjust the supply outputs per Procedure 7 4 Power Supply Test and Adjustment 1 Install the enclosure cover Spectrace Instruments QuanX Technical Manual Component Replacement 9 10 9 4 6 PS5 ECD Cooler Supply 1 1 1 See Figure 3 5 for the location of this supply Turn off the instrument power Disconnect the instrument power cord Remove the four rear panel screws which hold the enclosure cover in place Remove the enclosure cover by grasping it on the bottom of each side and sliding it directly forward Disconnect J13 from the motherboard located behind the card cage This is the cable
19. Spectrace Instruments QuanX Technical Manual Procedure Number 7 12 N A N A Procedure Number N A Procedure Number 9 7 1 7 6 See pump manual 7 Test and Adjustment Procedures Table of Contents Til Introduction c irae d elie eee RE ELE te dd A Age een 7 1 7 2 Fast Discriminator Adjustment einne iine e e eetas EEEN TE ESE AE ES 7 2 7 3 Energy Calibration TEE 7 3 7 4 Power Supply Test and Adjustment essent enren rennen nenne 7 5 TAA System Power Supplies 2 i eae ent p iz 7 5 7 4 2 ECD Cooler Power Supply pie ed eee e euer tr Ie eerte teen 7 8 7 5 Lateh Adq stiment r o eene a A dere 7 9 4 6 Interlock Test e eee ee a Gh tana anne 7 11 7 7 X ray Power Supply Control Board Adjustment seen 7 12 T o Radiation Survey cence e e e ue ta e s 7 14 4 9 Initial Energy Calibration ette trente eret eee ehe Adeo tee tee eee dee dede co 7 16 7 10 Gain vs Count Rate Range Admstment sese nennen 7 18 REN EAO ee 7 21 APA MIN RM T 7 23 T EE e ET 7 26 7 14 Sample Tray Height Adjustment eese nennen nennen enne 7 29 TAS sample Tray DEEN ee T e SR ee Rees 7 31 LEE 7 34 PALE E EE 7 36 TAS Stray Lines ue n eee pa ee ee ee petet ee one de ER ene 7 38 JT I8 DS tray EMmes ll 25KV eoe eH bete tee ede tene 7 38 7 18 2 Stray Lines III SOKV cocida dias 7 39 7 19 Mimimum Detection Lit uta iia 7 42 120 Voltag and Current Steps ener ee cede ege eee bip tede d
20. X1 scale meter reading 0 4 mR h 0 4 x 1 7 20 0 02 mR h x10 scale meter reading 0 4 mR h 0 4 x 10 20 0 2 mR h Verify that the corrected reading is 0 25 mR h or less corresponds to an uncorrected reading of 5 mR h Turn off the X rays Place a lead sheet over the detector window to protect it from excessive X ray flux Do not block any part of the primary X ray beam with the lead Install the sample tray in the chamber and put the scatter block in place over the X ray beam Repeat the same tests for the scatter block condition Record the higher of the two readings no sample versus the scatter block Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 16 7 9 Initial Energy Calibration Scope and purpose To set the hardware gain and zero adjustments close to the correct setting so that the automatic energy calibration routine can locate the peaks This procedure is required when the pulse processor board is replaced Test conditions Complete fully functional system System warmed up for at least an hour Fast discriminator checked and adjusted before starting this calibration Test equipment Universal adjustment tool tweeker or small flat screwdriver Spectrace OFHC copper calibration standard Procedure 1 Verify that the pulse processor GAIN switch is set to the 1 position 1 Start the QUANX program and press SETUP then SYS STAT 1 Adjust the coarse zero on the pulse process
21. cooler supply has a variable voltage output if it s low it could be a bad power supply ECD control board or sensor see next 3 causes Test per procedure replace if required Verify by substitution replace if required Sensor resistance 2250 Q at 25 C 3080 Q at 18 C Unplug connector to measure The cooler power on off entry on the DET SUPPORT screen is generated by the cooler power relay relay closed coolers on If it says off the ECD board may be bad relay not closed Also measure the cooler voltage at the detector terminal strip 4 pos 7 neg Verify on the ECD STATUS screen the base should be less than 21 C If it is see following causes Verify on the ECD STATUS screen The int cooler power supply regulates the current not the voltage If the int cooler voltage is less than 5 the power supply is bad If it is greater than 7 5 there is high resistance in the path see next cause Measure the current it should be 3 8 A Test the power supply per procedure The cooler power on off entry on the DET SUPPORT screen is generated by the cooler power relay relay closed coolers on If it says off the ECD board may be bad relay not closed Also measure the cooler voltage at the detector terminal strip 8 pos 3 neg Spectrace Instruments QuanX Technical Manual Procedure 7 4 2 5919 0207 J3 3 sense 5919 0207 J4 pins 8 amp 6 5919 0207 J4 4 5 amp J3 7 5 relay K1
22. procedure Otherwise the system will reset the gain DAC and restart the acquisition automatically This process will continue until the error value is very low 1 When this occurs the procedure will automatically terminate and Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 4 save the new DAC value This value is stored and will be reused until this procedure is executed again even if the computer is turned off It normally takes 5 to 15 minutes to complete the energy calibration If this procedure is terminated prematurely by pressing EXIT it asks whether the latest gain DAC value should be saved If the error is acceptably low 3 for most applications respond with Y If the error is too high respond with N to retain the old DAC value The energy calibration routine must then be restarted if a lower error is desired Spectrace Instruments QuanX Technical Manual 7 5 Test and Adjustment Procedures 7 4 Power Supply Test and Adjustment This procedure is presented in two parts The first part covers the basic system power supplies and applies to all instruments The second part addresses only the ECD cooler power supply and applies only to instruments equipped with an ECD 7 4 1 System Power Supplies Scope and purpose To measure the power supply voltages and make any required adjustments Test equipment Digital voltmeter DMM Test conditions None Procedure 1 Remove the mothe
23. 1 Contact factory Reference 5911 0207 TP2 Procedure 7 4 2 Procedure 9 3 7 Troubleshooting 10 23 Faulty ECD assembly Verify by substitution Procedure 9 6 2 FAST DISCRIMINATOR CANNOT BE ADJUSTED PROPERLY Cause Remedy Reference Detector preamp cable is Connect preamp cable 0150 0111 disconnected Output cable between the bias supply Connect BNC cable board and the pulse processor board is disconnected Faulty power supply Measure and adjust per procedure Replace Procedure if required 7 4 1 Faulty pulse processor module Verify by substitution replace if required Procedure 9 3 2 Excessive noise pickup See Resolution is poor FILTERS DO NOT POSITION CORRECTLY FAILED TO INITIALIZE FILTERS Cause Remed Reference Mechanical jam Check that filter wheel can be rotated one full rotation by hand with the power off Motor or sensor connector is Check connections at the chamber Figure 3 4 unplugged or a wire is broken distribution board Motor is J6 sensor is J5 If motor turns when the power is first turned on see the following causes Filter home signal is not being Verify with FILTER HOME LED on the 5919 0217 generated correctly due to chamber control board With the power on FHD rotate the wheel by hand As the flag pin passes through the sensor the LED should turn on always off otherwise If bad see the following causes Flag is not breaking the light Verify by inserting opaq
24. 2 blue If the X ray warning light comes on as normal now replace the board Note most likely failure is shorted capacitor C13 Explanation This means the current flowing through the chamber control board resistor R112 is low which the computer evaluates as ofi 2 Verify visually every other segment will be out making a diffused light dark pattern Also the chamber control board LIGHT ON LED is off If so replace the display board Verify by removing lid cover screws and starting the X rays with the board well clear of the lead Best to replace the board If not available adjust the display board pot to achieve 2 10V at the chamber control board resistor R112 Allow the light to run 10 minutes before making the adjustment Verify and replace the board The off signal trips at R112 voltage of 1 8V Explanation Chamber board J1 7 INTERIN signal is not at 24V Measure the 24V PS2 A output per procedure Spectrace Instruments QuanX Technical Manual Procedure 9 7 1 Procedure 9 4 1 Procedure 9 3 6 Procedure 9 3 5 Procedure 9 3 5 None given Procedure 9 3 1 Drawing 0110 0632 for interlock overview Procedure 7 4 1 Open interlock switch or connection Faulty chamber control board generated a false signal Symptom The computer gives a confirm signal error message Faulty chamber control board Symptom The computer gives a light current is high message
25. 2 5 volts e TP1 3 Base temperature C 62 0 13 8V 0 68V where V is in volts A typical operating temperature is approximately 20 C or 3 8 volts Spectrace Instruments QuanX Technical Manual Theory of Operation 4 22 e TPI 9 Ion pump current This point is most useful for relative measurements such as tracking trends rather than absolute measurements To measure the true ion pump current a measurement directly across J5 pins 5 and 6 is best the conversion is ImV 1A Spectrace Instruments QuanX Technical Manual 4 12 Theory of Operation DISCARD THIS PAGE Spectrace Instruments QuanX Technical Manual Theory of Operation 4 12 2 DISCARD THIS PAGE 5 Installation Table of Contents 5 T Introduction e Ie e ree ette taret eet tb cles ote E teense Chee etn 5 1 SD Site Preparation eet nete bee ERE EG ae etri en erede Pe qe E 5 2 5 2 A C d eis 5 2 2 2 2 Atmosphere cac DEE REED Ote EES 5 2 5 2 3 Space Requiremerits nsn eee ei pee ee eed 5 2 e A VIDEO tias tri iria las 5 2 5 2 5 Temperature ni Ee AE od e DC o ab od e tbe eee 5 3 52 6 Power Requirements in ette tpe eee reino a pede eee esed 5 3 25 2 T Telephone icc ee tee EE 5 3 3 3 Special Precautions eisenii ereen eR E A 5 4 2 OuanX Setup ete eoe teret eer teet nee A edt aeree voee itte ere 5 5 2 5 Personal Computer Setup iie Ht rte Ha eie o ee eese eee tis pret ie bea te ei ec CoD Rn 5 7 3 5 1 QUANX Program Installation alicatados 5 7 5 5 2 DOS Operati
26. 6 OFF 1 2 3 5 OFF 1 2 3 5 6 2 Settings of SW2 I O address OFF 1 2 5 6 ON 3 4 7 8 ON 3 4 5 6 7 8 N 3 4 5 7 8 N 3 4 7 8 N 3 5 6 7 8 N 3 5 7 8 N 3 6 7 8 N 3 7 8 N 4 5 6 7 8 N 4 5 7 8 N 4 6 7 8 N 4 7 8 20000000000 Spectrace Instruments QuanX Technical Manual 5 12 Installation 4 Ifthe switch settings have been changed from the factory settings the CONFIG SYS file must be modified To prevent DOS from using the memory area required for the ADC interface board the address block chosen must be reserved via a statement similar to X D800 DBFF in the CONFIG SYS file Note that the address must be entered in a 4 digit format Simply drop the last character from the address listed in Table 1 The complete line in the CONFIG SYS file would appear as DEVICE C DOS EMM386 EXE NOEMS X D800 DBFF with the address block chosen replacing the default values shown To make the new value active reboot the computer by pressing CTRL ALT DEL simultaneously 3 If the switch settings have been changed from the factory settings turn on the computer and run TXCONFIG Select the type of system being installed press ENTER and select COMPUTER At the COMPUTER PRINTER menu on the MEMORY ADDRESS USED line enter the address block that corresponds to the switch settings used The space bar may be used to step through the available options 3 Start the QUANX program by typing C gt quanx and test spectrum acquisition by running
27. 953 8 ADC Interface Board i RU tuer De eee etes id 9 6 VE Power Supplies 452 Rte rt ete ett d AA ote teins ould nde A 9 7 9 4 1 X ray High Voltage Power Supp 9 7 94 X PSI al BATES A eiecti e oO debs Geant ea ewes 9 7 9 4 3 PS2 24V Switching iei teret e ee I RH E obese tabu HEP Le CE ER en ut 9 8 9 4 4 PSS 12V Lifieat eerte A Cer RR 9 8 OAS E EE 9 9 9 4 6 PS5 ECD Cooler Suppl yasni nsa niii ER E e 9 10 9 4 7 Ion Pump Power Supply eite age e NEE Bees 9 10 9 5 Sample Chamber Components eese eere eren nennen tenente tenente 9 12 9 5 T Filter Wheel Assembly irr ideada 9 12 9 5 2 Sample Tray Drive Assembly nennen enne senten enn 9 12 9 5 3 Sample Spinner Drive Assembly eese nennen nennen 9 12 9 6 Detector Assemblies eee ree etel Feet eae Eed EUR ENS 9 14 JOTEN Detecta ere tetra ore te e IRE SEES ERE ET SEHR egen Deg 9 14 9 6 2 Electrically Cooled Detector BC 9 15 977 Miscellaneous Items ne reete eee eoi cente eta art NEEN eege 9 18 OLD A X ray TUDE c s eee tret dase ade aree e n rn mh Pede ee tees 9 18 9 7 2 X ray Tube Cooling BAM vs ete ett o e ette ae e tete ES 9 18 97 3 Enclosure Cooling Fan coccion Ug rd estes Ie e 9 19 9 7 4 Sample Chamber Lid Latch Assembly essere 9 19 9 7 5 Vacuum Pump Power Relays orreee iui aiiin airi i e ai 9 20 Spectrace Instruments QuanX Technical Manual 9 1 Component Replacement 9 1 Introduction This section contains procedures for the field replacement of va
28. Cause The ADC requires a logic reset Hardware calibration is too far out of adjustment for the system to compensate Hardware failure ACQUISITION FAILED TO INITIATE Remed Exit the program cycle the power off and on and resume operation Adjust the hardware calibration per Procedure 7 9 Initial Calibration See the troubleshooting chart in the next section No X ray counts were detected during the first second of the acquisition Cause Excitation voltage set too low for the filter selected No sample in the tray position selected X ray tube anode current set to zero Fast discriminator requires adjustment ADC locked up Hardware failure Remed Raise the X ray kV setting or choose a different filter Install a sample Select a new mA value Adjust to 150 25 with X rays off see Procedure 7 2 Exit program cycle the power off and on restart program See the troubleshooting chart in the next section Spectrace Instruments QuanX Technical Manual 10 6 Troubleshooting ADC failed to respond Retry previous task or check hardware and reload program The computer is not able to communicate with the ADC board Cause Random noise event ADC locked up ADC interface cable is disconnected or loose ADC board not inserted correctly in the card cage Hardware failure CHECK PRINTER Remed Resume normal operation Exit program cycle the power off and on restart progr
29. DVM Clip leads 1 Ohm 1 50 watt resistor mounted on a heat sink Adjustment screwdriver Special precautions In the following procedure you will use a high power resistor to simulate a load Take care that the resistor does not over heat during the adjustment procedure Complete the adjustments quickly after applying power because the resistor value changes slightly as it heats up Procedure The internal cooler supply is a current supply and the external cooler supply is a voltage supply The location of these outputs are shown in below INTERNAL COOLER EXTERNAL COOLER CURRENT SUPPLY RER VOLTAGE SUPPLY ECD Power supply top view 1 Turn off the instrument power Disconnect the instrument power cord 1 Disconnect the ECD control board J3 connector 1 Connect voltage source S sense terminal to the output terminal with a clip lead 1 Connect the 1 Q resistor to the current supply output 1 Plug in the instrument power cord The ECD power supply will be on even when the instrument power switch is off 1 Connect the DVM across the 1 Q resistor and adjust the current supply s I ADJ pot for 3 80 volts across the resistor 1 Connect the DVM to the voltage supply output Adjust the VOLT ADJ pot for 5 6 volts 1 Disconnect the 1 Q resistor from the current supply and measure the output voltage without a load The voltage should be between 9 5 and 10 5 volts 1 Unplug the power cord Disconnect the sense terminal c
30. ECD ion pump to turn off The procedure should be carried out in 30 minutes or less See Figure 3 5 for the location of this supply Turn off the instrument power Disconnect the instrument power cord Remove the four rear panel screws which hold the enclosure cover in place Remove the enclosure cover by grasping it on the bottom of each side and sliding it directly forward Disconnect the white in line connector J1 located in the cable connected to the supply bracket Verify that the red LED turns off Disconnect the wires from the battery Disconnect the cable from the supply s BNC output connector Spectrace Instruments QuanX Technical Manual 9 11 Component Replacement Remove the two screws below the battery Lift the supply battery assembly out Remove the battery and replace the power supply Reassemble the components by following the previous steps in reverse order EO eO be E Plug in the power cord and turn on the power Tap firmly a few times on the ECD ion pump with a screwdriver handle or similar object to ensure that the ion pump has started See Figure 4 3 for the location of the ion pump 1 Measure the voltage between the supply s ground and I M connections black and violet wires The voltage is proportional to the ion pump current 1mV 1A it should be between 0 2 mV and 20 mV Spectrace Instruments QuanX Technical Manual Component Replacement 9 12 9 5 Sample Chamber Components Replacement of th
31. ImV 1uA If less than 300 mV the I P CURRENT OK light should be on If it is off replace the ECD control board Verify by measuring the ion pump current signal with a voltmeter at the ECD board U5 1 TP1 9 x 10 and comparing with the ECHOA QV06 response Replace chamber control board if required LOW ENERGY SENSITIVITY IS POOR Cause Analysis conditions and or method are not optimized for the elements of interest Fast discriminator requires adjustment Remedy Contact a factory applications specialist Adjust the fast discriminator control for 150 25 counts sec with the X rays off Spectrace Instruments QuanX Technical Manual 10 25 Procedure 7 5 Procedure 9 3 1 Adjust per Procedure 7 5 Reference Procedure 7 24 or ECD STATUS Screen Procedure 9 3 7 5919 0207 ion current ok Procedure 9 3 1 Reference Procedure 7 2 10 26 Noise pickup caused high fast discriminator values forcing a f d readjustment based on this artificially high background noise level The f d threshold is now so high it is cutting off the low energy portion of the spectrum Low detector bias supply voltage Faulty pulse processor module Faulty ADC board Contamination of the detector s beryllium window Faulty detector assembly NO SPECTRUM IS PRODUCED ACQUISITION FAILED TO INITIATE Cause Excitation voltage set too low for the filter selected No sample in the analysis po
32. Instruments 1275 Hammerwood Avenue Sunnyvale CA 94089 408 744 1414 Attn Customer Service 2 1 1 Responsibility for Safe Operation X ray producing equipment should be used only under the guidance and supervision of a responsible qualified person All equipment operators must be given adequate radiation safety instruction as specified by governing state regulations Adequate precautions should be taken to make it impossible for unauthorized or unqualified persons to operate this equipment or to expose themselves or others to its radiation or electrical dangers Before utilizing the equipment it is suggested that all persons designated or authorized to operate it or supervise its operation should have a full understanding of its nature and should also become familiar with established safe exposure factors by a careful study of the appropriate documents listed below Spectrace Instruments QuanX Technical Manual Safety 2 2 e Security X ray Cabinet Systems Bureau of Radiological Health Performance standard for Cabinet X ray Systems 21 CFR 1020 40 Order from Bureau of Radiological Health FDA Fishers Lane Rockville MD 20852 e Industrial X ray Equipment National Bureau of Standards Handbook 114 ANS N543 1974 SD Catalog No C13 11 114 e Industrial X ray Equipment and Analytical X ray Equipment National Bureau of Standards Handbook 111 ANS N43 2 1971 SD Catalog No 13 11 111 Order from Superintendent of Document U S
33. Instruments QuanX Technical Manual Component Replacement 9 6 9 3 8 ADC Interface Board 1 1 1 1 This board is located inside the personal computer Turn off the computer power Disconnect the ADC interface cable from the rear of the board Open the computer case Remove the screw securing the board in place and remove the board Set the SW1 switch segments on the replacement board to match the old board Verify that SW2 is also set the same Install the replacement board by repeating the previous steps in reverse order Test the board by acquiring a spectrum Verify that the peaks look normal and that there are no extra or missing lines in the spectrum Spectrace Instruments QuanX Technical Manual 9 7 Component Replacement 9 4 Power Supplies Replacement of all the system power supplies is detailed below It is possible to replace the entire power supply tray as one assembly however these procedures address each supply individually 9 4 1 X ray High Voltage Power Supply 1 See Figure 3 2 for the location of this supply Turn off the instrument power 1 Remove the four rear panel screws which hold the enclosure cover in place Remove the enclosure cover by grasping it on the bottom of each side and sliding it directly forward 1 Disconnect both cables from the front of the supply The locking tabs on the sides of the lower connector must be depressed to remove it Do not touch the end of the high voltage cabl
34. Spectrace Instruments QuanX Technical Manual Component Replacement 9 14 9 6 Detector Assemblies Replacement of the liquid nitrogen or electrically cooled detector assemblies is detailed below The procedures are broken up into Removal and Installation sections to more clearly describe certain steps 9 6 1 LN Detector CAUTION The detector s beryllium window is extremely fragile Read the precautions at the beginning of this chapter before continuing Removal 1 1 Turn off the instrument power Remove the four rear panel screws which hold the enclosure cover in place Remove the enclosure cover by grasping it on the bottom of each side and sliding it directly forward Remove the screws securing the top left frame member to the chassis and remove the frame member Remove the single screw which holds the dewar mounting frame to the bottom of the chassis Disconnect the preamp cable connector from the bias supply board located in the card cage Remove the sample tray and the metal plate which covers the sample chamber components or the special sample handling stage if installed The cover plate is secured with special vented screws save these for reuse Remove the two socket head screws which fasten the filter wheel assembly to the baseplate Move the assembly aside it is not necessary to disconnect its cables Remove the sample spinner drive assembly if installed screws and move it aside It is not necessary to dis
35. Technical Manual 2 9 Safety 2 6 Asphyxiation Hazard Cryogen Boil Off WARNING Prolonged boil off of cryogens displaces air and the oxygen in it This can lead to asphyxiation without warning Store or use cryogens only in well ventilated rooms Nature of the hazard Liquefied cryogen is always boiling off a cold dense gas from the dewar in which it is kept The gas is colorless odorless and non toxic However it displaces the air and the oxygen in it that people need to breathe Preventive measures Make absolutely sure that in any room where cryogens are used or stored the ventilation is adequate at all times Emergency measures If a person should be overcome by lack of oxygen ventilate the area or move the person to an area with normal oxygen levels and administer appropriate first aid and call for help Spectrace Instruments QuanX Technical Manual Safety DISCARD THIS PAGE Spectrace Instruments QuanX Technical Manual 2 6 2 6 Safety 2 DISCARD THIS PAGE 3 Product Description Table of Contents 3 1 Introduction ee ote e cep e eet Ue titm boe eine 3 1 3 2 A Lour Of RE E 3 2 332 1 Overall System ERE eee Ro tet 3 2 3 2 2 Component Identification and Descrppon nennen 3 2 3 3 S PEC CAOS int costes pce ai 3 12 3 4 Outline Drawing e E e EO nb pe ceo tires 3 17 Spectrace Instruments QuanX Technical Manual Safety 2 6 3 1 Product Description 3 1 Introduction The Spectrace QuanX is a compac
36. V MONITOR should be between 24 30 and 25 70 kV The X RAY TUBE ANODE CURRENT should be between 1 88 and 2 08 mA 1 Press HARD COPY to obtain a printout of the values File this printout in your maintenance log for future reference 1 Ifthe system is equipped with an ECD press EXIT and ECD STAT Wait 30 seconds and verify that all the values are within the range specified on the screen 1 Press HARD COPY to obtain a printout File the printout for future reference Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 48 7 23 Helium Flush Operation Scope and purpose To perform a basic operational test and a high pressure stress test of the helium flush feature This test is only applicable if the system is equipped with this option Test equipment 10 80 psi variable pressure compressed air source Flow meter p n 5305 0003 Matheson Gas 7263 or equivalent if meter not available see alternate procedure below Test conditions The helium flush manifold must have been adjusted per its subassembly level test procedure Procedure Note This is a relative performance test designed to compare the instrument s performance against an expected value Because the flow is measured on the supply side of the internal pressure regulator the flow rate values specified are only valid at the specified pressure and also do not represent the true flow rate 1 Set the compressed air source to 80 psi 1 Insert
37. Verify by substitution replace if required Spectrace Instruments QuanX Technical Manual 10 15 Procedure 9 3 4 Procedure 9 3 4 Procedure 7 4 1 Procedure 5 5 3 Procedure 9 3 8 Reference Section 39 Procedure 9 7 3 for replacement Procedure 9 3 1 Reference Procedure 7 2 Procedure 9 3 3 Procedure 9 3 2 10 16 Poor resolution or detector tailing Faulty detector assembly Troubleshooting Run resolution test with manganese to check for tailing 5k peak to background should be greater than 400 If the resolution is ok and the peak to background is low replace the detector assembly If the resolution is poor see Resolution is poor Verify by substitution replace if required CHAMBER CONTROL BOARD DOES NOT COMMUNICATE CHAMBER FAILED TO RESPOND Cause RS 232 serial communications connector is loose or disconnected from the computer Chamber control board requires a logic reset The enclosure control board is locked up attempting to locate the sample tray home position Faulty power supply or adjustment required Faulty chamber control board Faulty computer COMI port Bad connection in the RS 232 cable DEAD TIME IS HIGH Remedy Check the COMI connection on the back of the computer Turn the power off for 5 seconds and then back on Resume operation Verify by watching the tray after turning on the power It should rotate change direction
38. access to the memory will continue to have access to the memory until completion of the read or write cycle When both the ADC and the computer try to access the memory within one clock cycle the ADC is granted access first When the ADC reads or writes the two least significant bytes of the data memory the most significant byte is latched into a register or written into the memory from the same register This register is located in the ADC I O space When the computer reads the least significant byte of the data memory the two most significant bytes are latched into a pair of registers These two registers are read when the computer reads the next two memory locations When the computer writes the least significant byte of the data memory the two most significant bytes are written into memory from two different registers These two registers are written to when the computer writes to the next two memory locations Communication The ADC and the computer communicate with each other through registers located in their I O spaces The ADC uses interrupts for handshaking the computer employs polling Whenever the computer sends a command to the ADC it writes two bytes which represent the command into a pair of registers This generates an interrupt to the ADC that tells it the computer has a command for it The interrupt is cleared when the ADC reads the two bytes The computer will write into the registers only after it has determined that the
39. arcing is the problem by setting 5919 0161 J4 amp failure symptoms The error the program to service mode via the J5 messages listed above are a likely TXCONFIG program Run at the lowest kV response Typically arcing is kV setting check that the problem is gone sensitive Better test all the above plus unplug J4 amp J5 from the X ray control board and jumper J5 pins 4 amp 5 on the board Contaminated high voltage cable Remove the cable from the tube and power supply Clean both ends using isopropyl alcohol and a lint free cloth Reinstall without touching the clean ends Faulty high voltage cable Verify by substitution replace if required Contaminated high voltage connector Clean the inside of both connectors using on the tube or power supply isopropyl alcohol and a lint free swab Faulty X ray tube Verify by substitution replace if required Procedure 9 7 1 Faulty X ray high voltage power Verify by substitution replace if required Procedure supply 9 4 1 INTERLOCK CIRCUIT FAILURE DETECTED SERVICE REQUIRED Cause Remedy Reference Meaning The chamber board detected a state where the chamber lid was open but the interlocks were not broken Random noise event Open the chamber lid if the circuits are functioning correctly the error will be cleared automatically If unsuccessful try turning the power off and on to reset the board Spectrace Instruments QuanX Technical Manual As the sample chamber li
40. bending its lever with pliers This switch must open only when the lid is actually locked Use a tool to push the solenoid plunger back and forth Adjust the switch trip point click sound to be after the solenoid plunger has overlapped the tongue but before the end of the plunger travel to insure some switch over travel See Figure 7 5 b below BEND LEVER b S a FULLY LOCKED POSITION b SWITCH TRIP POINT ADJUSTMENT FULLY LOCKED POSITION SWITCH TRIP POINT Figure 7 5 Lid latch adjustment Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 10 The switch which is actuated by the lid tongue see Figure 7 6 must be adjusted to close before the large black chamber interlock switch closes Turn on the system power make sure all interlocks are closed so that when the chamber lid is closed the INTERLOCK DS2 LED on the x ray control board lights Bend the switch lever so that as the lid is closed this switch closes click sound well before the LED lights Close the lid completely and feel the switch lever it must have a tiny bit of free play If it doesn t it will push the chamber lid up and prevent it from sealing for vacuum properly The correct adjustment of this switch is a compromise between the two constraints BEND LEVER TO SET TRIP POINT LEVER i FREE PLAY Figure 7 6 LID CLOSED sense switch adjustment Spectrace Instruments QuanX Technical Manual 7 11 Test and Adjustment Pro
41. cause its output to be at maximum 30 or 50kV Applying half the reference voltage generates half the maximum output 5V control 2 25kV output for 50kV supply and so on Voltage control DAC U8 determines the percentage of the reference voltage that is connected to the control input The circuit that generates the control voltage consists of Q4 U8 and U9 The reference voltage from the power supply is used as the analog input voltage for digital to analog converter U8 after being buffered by half of U9 The digital input to U8 determines what fraction of the analog input voltage is output by U8 This output is amplified by the other half of U9 and by Q4 to produce the control voltage The gain of this amplifier is switch selectable for either 30 or 50kV systems This is necessary since full scale output of the DAC is a smaller percentage of the analog input voltage on 30kV systems than on 50kV systems The gain is increased on 30kV systems so that a 30kV setting produces a control voltage equal to the reference voltage R30 and R33 are gain trims for the two ranges Spectrace Instruments QuanX Technical Manual Theory of Operation 4 4 Interlocks Interlocks are designed to prevent operators technicians or bystanders from being exposed to X rays Connectors J3 and J5 on this board carry interlock signals and power for the X ray high voltage power supply The interlock circuit is described in the following section Spectrace Instruments QuanX
42. for up to 72 hours It is automatically recharged when the instrument power cord is plugged in The ion pump power supply is a high voltage 3kV low current power supply used to operate the ECD ion pump The power supply operates on 12V DC which is supplied by the instrument power supplies when the instrument power cord is connected to an AC power source or by the backup battery when the power cord is unplugged Spectrace Instruments QuanX Technical Manual Product Description 3 10 Figure 3 6 shows a rear view of the QuanX Each item identified with a callout is discussed below Error Not a valid link Figure 3 6 Rear view The power on off switch controls the power to part or all of the instrument depending on the model For instruments equipped with a LN detector the switch controls all power to the instrument For ECD equipped systems the power switch only controls the power to the card cage To prevent accidental warmup of the detector the power supplies that support the ECD coolers and ion pump remain on even when this switch is in the off position For these instruments the power cord must be disconnected to remove all power The instrument power input and fuse is the connection point for the primary power cord The connection is made via a standard IEC 320 inlet The inlet module has UL CSA and VDE safety agency approvals It is rated for line voltages of 115 or 230 VAC if the system line voltage selection switches are set
43. installation of the QUANX program ECHOA will be located in the SPECTRAC directory To run the ECHOA program the computer and the RS 232 serial communication path to the control board must be operational ECHOA obtains the information required to initialize the computer s serial communication port from a system configuration file This file is created and modified by use of the TXCONFIG program When ECHOA is executed the communications port address and interrupt level are displayed At this time the operator may specify new values for ECHOA to use during the communication session The default setting for COMI and IRQ4 are always used For reference the RS 232 parameters are 9600 baud 8 data bits 1 stop bit 8 3 1 Starting the ECHOA Program 1 Exit the QUANX program if required to return to the DOS prompt 1 Type the program name followed by the Q argument which sets the program to the baud rate used by the QuanX For example C gt ECHOA Q Typing ECHOA without the Q argument will cause an instruction menu to appear 1 When the program has finished loading press the ENTER key several times Z1 should appear on the screen indicating that communication with the chamber control board has been established If the message NO CR FROM CHAMBER is displayed it means that the communication has not been established Try pressing ENTER a few times if Z1 appears ignore the error message If there is no response verify that the serial co
44. is an adjustment to set the current through the luminator which vary from unit to unit due to the LED forward voltage drop Failure of any segment whether open or short will prevent X rays from being generated CAUTION The luminator Dl is susceptible to damage from the heat of soldering The maximum rated temperature for soldering is 500 F for 3 seconds The green Power light D2 is on anytime the instrument power switch is on The red Detector Temp light is a flashes when the LN detector LN level is low or when the ECD detector is above normal operating temperature The flasher circuit is on the chamber control board Spectrace Instruments QuanX Technical Manual 4 17 Theory of Operation 4 10 Bias Supply Board The circuit for this board is shown in schematic 5919 0189 The board consists of a detector bias supply a FET protection circuit and a liquid nitrogen level or detector temperature monitor Two versions of this board are used The LN detector version is part number 5911 0196 and the ECD version is 5911 0194 They differ only in the bias voltage setting and the low LN alarm circuit characteristics Detector bias supply The heart of the bias supply is a bridge oscillator whose amplitude is voltage controllable This oscillator consisting of amplifier U5 and its associated components C20 C23 R34 and R43 determines the operation frequency which is nominally 25 30 kHz The oscillation amplitude is determined by the
45. is not Check the yellow jumper wire inside the bias positioned correctly supply module It should be inserted in the 600V socket LN or the 300 or 400V socket ECD Faulty detector assembly Verify by substitution replace if required REPEATABILITY OF ANALYSIS RESULTS IS POOR Cause Remedy Analysis conditions and or method Contact a factory applications specialist are not optimized for the elements of interest Fast discriminator requires Adjust the fast discriminator control for 150 adjustment 25 counts sec with the X rays off X ray stability is poor Verify by running the Stability test per procedure If stability is poor see X ray stability is poor Detector resolution is poor or is not Verify by running the Stability test per stable procedure If the FWHM also the peak count stability is poor or if the FWHM is high see Resolution is poor Note resolution can be affected by fan vibration which changes with temperature If suspected run resolution with fans at maximum by unplugging sensor lead on tube fan and heating enclosure fan sensor Sample positioning problem For systems with a sample tray run the Tray Accuracy test or run with the single sample tray installed to verify RESOLUTION IS POOR ZERO WIDTH IS HIGH CHECK DETECTOR STATUS Cause Remedy Pulse processor count rate range Select a lower range selected is not suitable for the attempted analysis Pulse processor gain switch is not set
46. nature rather than liquid or oil an air stream may be sufficient to remove the particles Use the canned air to blow a stream of air parallel to the surface of the window as much as possible as shown in Figure 7 10 Start with the nozzle about 6 inches 15cm away and slowly move it closer to the window until the particles are removed Do not allow the nozzle to come closer than 2 inches 5cm to the window If the window appears clean replace the collimator and filter wheel assembly The flat portion of the collimator snout should be horizontal If an air stream is not sufficient to clean the window a liquid wash is required Place an absorbent towel in the sample chamber under the window area Using the squirt bottle of methanol direct a fine stream of liquid at the metal area above the window as shown in Figure 7 10 and allow the liquid to run over the window Do not allow the stream to strike the beryllium material directly Dry the window using the canned air as described above This process may be repeated if required If the window still isn t clean a stronger solvent or factory assistance is required Please contact the Customer Service department for advise Replace the collimator and filter wheel assembly AIR FLOW DIRECTION Figure 7 10 Window cleaning detail LN version shown Procedure X ray tube window The X ray tube window is approximately 10 times the thickness of the detector window Therefore it is not
47. ne nee 7 2 1 3 Energy Calibration rtt pe e eter etes 7 3 7 4 Power Supply Test and Adjustment essent rennen 7 5 7 5 Watch Adjustment i tete bet pet HR HE HERR RE tee pe pee elige lt ceo Haee eg 7 9 TO Interlock Test ette rm beet ENEE 7 1 7 7 X ray Power Supply Control Board Adjustment serene 7 12 TS Radiation Survey o eee ee tice eee ee e eee eb teet lade ind 7 14 7 9 Initial Energy Calibration pecenie e e i ie 7 16 7 10 Gain vs Count Rate Range Adrmustment esee 7 18 7 11 ResolutiOh ue niet n ere e ete Haee ere te pe et Hd 7 21 7 12 el e EE 7 23 7 13 Repeatability sie eot id iio deed 7 26 7 14 Sample Tray Height Adjustment sese 7 29 7 15 sample Tray ACCUracy ien eet eee eee reset tege ena 7 31 7 16 EK ce Uc EE 7 34 7 17 Pla Ree ru ese tette 7 36 7 18 Stray Lifi s oue t ale EEN EE 7 38 7 19 Minimum Detection Limits cessent 7 42 7 20 Voltage and Current Steps 7 44 7 21 Chamber Vacuum Fest ete e rent e eet eee retina 7 46 7 22 System Status Voltages eir ee ee e eret ree see teen 7 47 7 23 Helium Flush Operation eese 7 48 7 24 Detector Temperature Measurement ECD sees 7 50 7 25 Beryllium Window Cleaning Drocedure eee 7 51 8 Diagnostic Software Sel Ieren ee E 8 1 8 2 Diagnostic Disk Installation cessent rennen 8 2 83 BCHOA PROGRAM ette tecto d aet eet eset eel t Het E E Recte renes 8 3 8 4 QUANXA Service Mode onia e eoe ee Hee i
48. pan and X ray tube body Test the interlock circuit Replace the vacuum pump oil optional equipment Periodic Maintenance Comments The Resolution and Stability test performs repetitive analysis on a sample until it is stopped Instability due to changes in the X ray tube output or peak shift will be detected Save the printout in a maintenance log By maintaining a record of the system voltages trends may be detected Also this history information is very helpful for comparison purposes when diagnosing hardware problems Use the HARD COPY key to print a copy of the SYSTEM STATUS GENERAL STATUS and ECD STATUS if applicable screens Allow at least two screen updates before printing Save the printouts in a maintenance log The oil level should be in the middle of the sight glass Comments Some states require regular safety testing If so an interlock test and a radiation survey are normally required The results must be maintained in a log book See Section 2 Safety for more information Comments If the instrument is operating in a dirty environment the air pan may collect debris Also the X ray tube and shroud may be covered with dirt which reduces tube cooling efficiency If significant quantities of dirt are found fan filters should be installed To verify proper operation of the interlock circuit If the oil appears dark brown or has a burnt smell it should be changed using the same type of oil
49. substitution replace if required Measure and adjust per procedure Replace if required DETECTOR HEAT SINK TEMPERATURE IS HIGH ECD ACQ ABORTED COOLERS ARE OFF ACQ ABORTED ECD THERMAL SHUTDOWN Cause Blocked vent opening Disconnected hose ECD fan power is disconnected or polarity is reversed or the fan is faulty Remedy Vent opening on left side must have at least 4 inches clearance flexible hos n the heat Check larg connected betw sink and fan Check fan cable J11 on motherboard Check for 24V of correct polarity at the fan if good replace fan Spectrace Instruments QuanX Technical Manual Reference Procedure 7 2 Figure 3 4 Figure 3 6 Procedure 7 20 board test Procedure 7 7 board adjust Procedure 9 3 4 Procedure 9 3 2 Procedure 7 4 1 Reference Faulty ECD control board generated false signal Faulty temperature sensor or bad connection to it Troubleshooting Verify and replace the board Sensor resistance 2250 Q at 25 C 1470 Q at 35 C Unplug connector to measure DETECTOR HIGH VOLTAGE BIAS IS OFF ACQ ABORTED DET BIAS VOLTAGE OFF Cause Detector preamp cable is disconnected LN dewar is empty The detector coolers are not on ECD The detector coolers have not been on long enough ECD The detector temperature is too high ECD The HV light on the bias supply module is off because The bias supply module i
50. the X rays Highlight SAVE ON DISK and press SETUP Change the file number to 200 press ENTER and EXIT 1 Highlight SPECTRUM PROCESSING and press RUN Enter 15 for the number of samples to process 1 Highlight ANALYSIS TECHNIQUE and press SETUP Change the mode to Standardize Set print statistics to Yes EXIT back so that ANALYSIS TECHNIQUE is highlighted and press RUN Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 28 1 The system will print the deviation for each position and calculate an overall sigma 1 Verify that the sigma is 0 25 or less Spectrace Instruments QuanX Technical Manual 7 29 Test and Adjustment Procedures 7 14 Sample Tray Height Adjustment Scope and purpose To set the height of the sample tray to compensate for variations in the x ray spot location and alignment Proper height adjustment maximizes the detected flux and minimizes the sensitivity to tray flatness Test equipment Short tray pads or tray height adjustment fixture Thin about 0 015 washers Brass sample Test conditions Optional The diagnostic diskette contents has been installed and the QUANX program has the active directory set as C SPECTRAC QTESTLN or C SPECTRAC QTESTECD for an LN or ECD system respectively Procedure 1 Use special short tray pads or a tray height adjustment fixture to position the tray at a low starting point about 0 25 1 Place the brass sample in tray position 1
51. the bottom of each side and sliding it directly forward Remove the X ray high voltage power supply as described in Procedure 9 4 1 Detach both hoses from the X ray tube cooling shroud Disconnect both connectors from the X ray tube Do not touch the end of the high voltage cable or allow it to become dirty If required it may be cleaned with isopropyl alcohol Disconnect the white in line connector in the shroud temperature sensor cable Remove the sample tray and the metal plate which covers the sample chamber components or the special sample handling stage if installed The cover plate is secured with special vented screws save these for reuse Remove the two socket head screws which fasten the filter wheel assembly to the baseplate Move the assembly aside it is not necessary to disconnect its cables While supporting the tube with one hand remove the two screws holding it in place These Screws are accessed from inside the sample chamber on either side of the tube collimator These are special vacuum sealing screws with an integral o ring save them for reuse Remove the X ray tube and shroud Loosen the two screws in the shroud and slide the tube out If necessary remove the label from the new tube and place it on the outside of the shroud The label interferes with the tube cooling Slide the new tube in the shroud and tighten the shroud screws moderately just until the tube is held tightly Transfer the collimator fro
52. the energy calibration routine If spectrum acquisition does not function properly no peaks solid block random lines or dropouts etc choose a different address and repeat steps 2 5 Note The first time spectrum acquisition is attempted a few basic steps should be taken to ensure that the instrument is capable of producing X rays and generating a spectrum Failure to ensure this basic level of performance may cause an unrelated problem to be misinterpreted as an unsuitable address setting The following steps are recommended e Place the copper calibration disk in the sample chamber tray position 20 if installed e Before starting the energy calibration function check the fast discriminator setting on the system status screen If it is not between 50 and 300 it must be adjusted per procedure e Before starting the energy calibration function open the left top cover and bypass the interlock switch by pulling up on its actuator Verify that the PA RESET light on the pulse processor flashes at a rate of less than 5 per second with the X rays off and at a much higher rate even on constantly when the X rays turn on 5 5 4 Printer Configuration This section discusses the printer settings required to insure proper operation with the QUANX program Because many different printer models are compatible the information given is of a general nature and no specific models are addressed Any printer will print text such as procedure menus a
53. the previous steps in reverse order Press firmly on the board until it snaps into place Perform the following procedures a 7 2 Fast Discriminator Adjustment b 7 3 Energy Calibration c System standardization should be checked before beginning quantitative analysis 9 3 4 ADC Board l 1 1 1 See Figure 3 4 for the location of this board Turn off the instrument power switch Disconnect the ADC interface cable from the top of the board Remove the board by pulling out on the two ejection ears located on the top of the board Lift the board out of the card cage Install the replacement board by repeating the previous steps in reverse order Press firmly on the board until it snaps into place Perform the following procedures a 7 2 Fast Discriminator Adjustment b 7 9 Initial Energy Calibration d 7 3 Energy Calibration 9 3 5 Display Board 1 1 1 Turn off the instrument power switch Disconnect the X RAY ON warning light cable from the rear panel Open the sample chamber lid Remove the ten phillips head screws which attach the lid outer cover to the metal portion of the lid With the lid open gently lift the outer cover up and away from the metal portion of the lid 1f closed the lid will spring open rapidly due to the reduced weight The warning light cable will remain attached to the cover the cable connector must be routed through the cutouts in the lid hinge to finally free the cover
54. the vacuum sensor by 100 filters it and U33B acts as a comparator to generate the VACUUM OK signal when the TP11 voltage falls below the TP2 voltage set by SW3 SW3 is used as a simple means of calibrating the board to the individual sensor which is required because the sensor output varies from one to the next A switch is used so that a replacement board may be easily calibrated by matching the switch setting to the original board The OK trip point is set for 750 1000 mTorr VR3 is used to null the U33A input offset voltage R150 and R144 are used to bias the entire input stage slightly positive for noise rejection and single supply op amp operation The sensor output TP12 TP10 changes by about 3mV from atmosphere to 750 mTorr LED D1 is a visual indication of the VACUUM OK signal on 0K X ray tube power control The board controls the X ray tube voltage and current via a 3 wire serial interface to the 5911 0220 X ray control board The three control lines are DATA WRI and STR The data is sent over the DATA line most significant bit MSB first The MSB selects either the voltage or the Spectrace Instruments QuanX Technical Manual Theory of Operation 4 14 current control DAC The other seven bits set the value of the selected DAC The STR signal indicates a new bit The WRI signal writes the value into the DAC Communication with the computer The microcontroller communicates with the personal computer over the RS 232 serial in
55. to 34 C ECD model 32 to 86 F 0 to 30 C 20 to 80 RH non condensing Spectrace Instruments QuanX Technical Manual Product Description 3 16 UTILITY REQUIREMENTS amp FUSING Power not including PC or vacuum pump Power optional vacuum pump Power personal computer PC system Fuse instrument power Fuse vacuum pump power Fuse convenience outlets OPTIONAL EQUIPMENT Helium Flush 100 120 200 240 VAC 5 2 5 A 50 60 Hz single phase LN model 350 watts maximum ECD model 500 watts maximum 115 230 V AC 50 60 Hz 700 watts 300 500 watts typical Type 5x20mm fast acting high capacity IEC 115 VAC operation 5A 230 VAC operation 2 5A Type 5x20mm time lag 115 VAC operation 7A UL 230 V AC operation 4A IEC Not fused Input pressure range 15 to 65 psig 103 448 kPa Consumption flow rate 2 minute purge 15 scfh 425 1 h during acquisition 5 scfh 142 I h Fitting 4 inch hose barb Spectrace Instruments QuanX Technical Manual 3 17 Product Description 3 4 Outline Drawing 35 27 f ty d 9 nm fefr p prmpe fr Y LUN sc y N E Pd N LZ 5 ar i E lt N X N S S X N he Z IN S Ki ES Sa y c gt o C 2 gt 2 1 4 A i J RR Figure 3 7 Physical dimensions front and right side
56. to become a logic level signal called CONFIRM This signal is read by the computer and the chamber board EPROM program to determine if the X rays are actually on or off A series of LEDs is included at each step of this sequence for troubleshooting purposes The LED names which are self explanatory are D8 LID CLOSED D6 LID LOCKED D3 INTERLOCK IN D5 ENABLE LIGHT D4 LIGHT ON and D2 INTERLOCK OUT Also a logic level signal is available to the microcontroller at each step of the process so that automatic troubleshooting assistance can be provided in the form of operator error messages Spectrace Instruments QuanX Technical Manual Theory of Operation 4 16 4 9 Display Board X ray On Warning Light The part number of this board is 5911 0218 and the circuit for this board is shown in schematic 5919 0218 This board illuminates the X RAY ON warning light the Power On light and the Detector Temp light Each are described below The primary component of this board is the LED luminator D1 This device uses 8 red LED segments shining light into the edge of a plastic body The plastic is treated for maximum optical reflection The LED segments are wired as 2 parallel branches of 4 LEDs in series They are powered by a signal from the 5911 0217 chamber control board The current through the LEDs is monitored by the chamber board as part of the interlock circuit so a regulator U1 is used to eliminate sensitivity to input voltage variations R6
57. to locate the flag center and stop If it doesn t see Sample tray failed to locate home Check 5 V PS1 per procedure Adjust or replace as required Verify by substitution replace if required Perform port loop back test Jumper COMI port pins listed below on computer and run ECHOA Q Anything typed on keyboard should appear on the screen if the port is working correctly 9 pin connector 7 8 4 6 2 3 25 pin connector 4 5 6 20 2 3 Use an ohmmeter to perform a pin to pin check of each connection DEAD TIME TOO HIGH CHANGE PARAMETERS CHECK DETECTOR STATUS Cause If dead time is high with X rays off Fast discriminator requires adjustment ADC interface cable is loose A board is not inserted correctly in the card cage Remedy Adjust fast discriminator control for 150 25 counts sec with X rays off Turn off the power Reseat the ADC interface cable connections at each end Turn off the power Reseat all the boards firmly Spectrace Instruments QuanX Technical Manual Procedure 9 6 Reference Procedure 7 4 1 Procedure 9 3 1 Reference Procedure 7 2 Figure 3 6 Troubleshooting 10 17 Preamp reset rate X rays off is See Preamp reset rate is too high above 1 reset per 2 sec LN or 10 resets per sec ECD Detector temperature is above 190 See Detector temperature is too high ECD Ion pump current is above 20 See Jon pump current is high ECD
58. to tasks the operator may complete for technical troubleshooting tasks the reader is directed to the troubleshooting chart in the next section of this manual e A Technical reference is supplied for the service technician The information supplied includes the electrical signal responsible for the specific error message and its location in the system documentation Spectrace Instruments QuanX Technical Manual 10 4 ACQ ABORTED COOLERS ARE OFF Troubleshooting The acquisition was stopped because the X ray detector coolers are off Cause Attempting to run X rays when detector coolers are off Detector coolers turned off automatically due to high heat sink temperature Technical reference Remed Turn detector coolers on before starting an acquisition See the troubleshooting chart in the next section See schematic 5919 0207 ECD control board signal COOLERS ON ACQ ABORTED DET BIAS VOLTAGE OFF The acquisition was stopped because the detector high voltage bias is off Cause The detector coolers are not on ECD The liquid nitrogen level is low LN The preamp cable is not connected Hardware failure Technical reference Remed Turn on the detector coolers or fill the dewar Connect the cable to the bias supply in the lower card cage See the troubleshooting chart in the next section See schematic 5919 0194 bias supply board signal HV ON ACQ ABORTED ECD THERMAL SHUTDOWN The
59. tools Safety precautions Lifting hazard The QuanX weighs between 175 lb 80kg and 200 Ib 91kg depending on options installed If lifting must be done manually it requires two or more people The correct place to grasp the enclosure is directly under the frame rails located around the perimeter of the base Procedure 1 Unpack the QuanX from its shipping container Place it on a bench or table top 1 Verify that both AC line voltage selection switches on the rear panel are set correctly for the local line voltage If they are not reset both switches and also install the correct value instrument and vacuum pump fuses if required 1 Plug the instrument power cord into an appropriate outlet Do not turn on the power switch at this time Note For ECD version instruments the fans will start even when the power switch is off 1 LN version Fill the dewar with liquid nitrogen using a funnel and appropriate personal safety gear Expect large quantities of gas to escape rapidly as the LN contacts the warm dewar Pour slowly to reduce splashing until the LN begins to flow smoothly ECD version Open the left top cover and switch the COOLERS switch to the ON position left This switch is located on the ECD control board and is shown in Figure 3 5 The COOL ON light should turn on the EXT COOL OK light should turn off and the HEAT SINK OK and I P CUR OK lights should remain on The EXT COOL OK light should turn on within ten minute
60. view DIMEN NS CENTIMETER INCH Spectrace Instruments QuanX Technical Manual DISCARD THIS PAGE Spectrace Instruments QuanX Technical Manual DISCARD THIS PAGE 4 Theory of Operation Table of Contents 4T Introduction Aem e ree et teet esp ti lese tote d onset hee dea 4 1 4 2 X ray RL ierat e t Rte bete telae ee esee teo E 4 2 4 3 X ray Control Board ae UM ate rtm 4 3 4 4 Safety Interlock Circuit seneo ere ti unen ee reete eode we Ee ERE eed eee 4 5 4 5 Electrically Cooled X ray Detector PCD rennen emen 4 7 4 6 Liquid Nitrogen Cooled X ray Detector cee eeeeseceseceseceseeeseeeseeeseeeeseeesneseneseaeeeseeenaeenaees 4 9 Abed PPS AIP MTEL EE 4 11 4 8 Chamber Control Board uie e HH eet eei E Dose te 4 12 4 9 Display Board X ray On Warning Lehr 4 16 4 10 Bias Supply Board eene etre dert eet PR EH ete tee Het ees 4 17 4 11 ApCntetrt ce Borda 4 19 412 ECD Control Board 5 cce c p teo e EE 4 20 Spectrace Instruments QuanX Technical Manual 4 1 Theory of Operation 4 1 Introduction This section describes selected portions of the QuanX in detail The presentation consists of descriptions of the various components introduced in Section 3 For most descriptions it is assumed that the reader has the relevant schematic or block diagram at hand for reference Spectrace Instruments QuanX Technical Manual Theory of Operation 4 2 4 2 X ray Tube The source for illuminating the samp
61. with a red orange and two black wires Release this cable from any cable clamps all the way back to the ECD board J3 connector Disconnect J3 from the ECD control board Remove the two board mounting screws near J3 and free the J3 cable from under the board Disconnect the ECD cooler supply fan wires from J3 6 two red and J3 4 two black Remove the four screws which attach the ECD power supply bracket to the top of power supply and remove the bracket and cooling fans assembly Disconnect the white in line connector J1 located in the supply s transformer cable Remove the green yellow wire safety ground wire from the supply chassis This is the ground wire with a dedicated screw not the ground wire using a transformer screw Remove the two nuts and two socket head screws which secure the power supply to the ECD support tray Lift the power supply out of the instrument Install the replacement supply by executing the previous steps in reverse order Turn on the power and use the ECD STAT screen to verify that the cooler voltages are within the normal range The external cooler voltage will be high until the ECD has reached operating temperature 9 4 7 Ion Pump Power Supply WARNING Electrical shock hazard The power supply output is approximately 3000 volts DC Connect or disconnect the supply s output cable only when the red LED located near the bottom of the supply bracket is off CAUTION This procedure will cause the
62. 1 5 General Information Repackaging for Shipment Whenever possible packing materials should be saved for use when components must be returned Sensitive components such as the X ray tube and the detector assembly require special care in packing Call Spectrace Instruments customer service for instructions Spectrace Instruments QuanX Technical Manual 2 Safety Table of Contents ZA IO ee ehe p e eee eeu als eL eee do ese pet eoe pce Rn 2 1 2 1 1 Responsibility for Safe Operation esee eene rennen nennen 2 1 2 1 2 Responsibility for Maintenance sees nenne ener enne nennen enne 2 2 2 1 3 Survey Meters and Dosimeter Badges esee eren enne 2 2 2 1 4 State Mandated Safety Requirements essent nennen rennen 2 3 2 1 5 IEC 1010 1 Safety Requirement essere enne en rennen 2 3 2 2 Radiation Hazard 2 X rays ees ib 2 5 2 3 Electrical Shock Hazard High Voltage esee rennen 2 6 2 4 Poisoning Hazard Beryllium Window eese enne en nre 2 7 2 5 Cryogen Burn Hazard Liquid Nutrogen A 2 8 2 6 Asphyxiation Hazard Cryogen Boil Off AAA 2 9 Spectrace Instruments QuanX Technical Manual 2 1 Safety 2 1 Introduction The QuanX system has been designed to meet all safety requirements applicable to industrial electrical and radiation devices However potential hazards exist in the operation and service of all electrical equipment In addition the Q
63. 10 Gain vs Count Rate Range Adjustment Scope and purpose To adjust the gain trim pots of the pulse processor to eliminate variation in gain between the low medium and high ranges Test equipment Pulse processor extender board P N 5610 0159 20 inch BNC to BNC cable Small flat screwdriver or adjustment tool Copper sample Test conditions The energy calibration must be close enough to the correct setting to enable the computer to locate the peaks while running ENRGY CALIB If it is not perform Procedure 7 9 Initial Energy Calibration first Procedure 1 Put the pulse processor board on an extender board Use a long BNC cable to connect the input signal Verify that the pulse processor GAIN switch is set to the 1 position 1 Start the QUANX program Press SETUP and SYS STAT 1 Verify that the ZERO DAC value is less than 300 If it is not adjust the ZERO pot on the pulse processor Verify that the FAST DISCRIMINATOR is between 100 and 200 If it is not adjust the FAST DISC pot on the pulse processor power must have been on at least 15 minutes Calibration of high count rate range 4 Place a copper sample in tray position 20 Press ENRGY CALIB from the procedure menu to start an energy calibration acquisition 1 Press ACQU MENU SYS STAT COUNT RATE and set the pulse processor to the High range Press EXIT 1 Make sure that the dead time is approximately 50 If necessary press ACQU PARM and adjust the tu
64. 2 mA steps and checking the dead time See the LOW CURRENT TEST column of the table below for typical values Stop when the current is 02 mA NOTE It is normal for the dead time to fluctuate plus or minus a few percent about the nominal value Pause at each step long enough to determine an average value Spectrace Instruments QuanX Technical Manual 7 45 Test and Adjustment Procedures LOW CURRENT HIGH CURRENT DEAD TIME TEST mA TEST mA 96 0 10 1 00 50 0 90 47 0 08 0 80 43 0 70 39 0 06 0 60 36 0 50 33 0 04 0 40 29 0 30 24 0 02 0 20 20 4 Repeat step 3 starting at 20 kV 21 ECD and 1 00 mA If necessary adjust the tube voltage for 50 dead time Measure the dead time at currents from 1 00 to 0 20 in 0 10 increments Compare with the typical values in the HIGH CURRENT TEST column of the previous table 4 Setthe following conditions Tube voltage 4kV Tube current 0 02 mA Filter Cu thick 4 Press SYS STAT then GEN STAT to view the general status page Wait for the X RAY H V CONTROL to be updated at least once Check that the control voltage is within the range specified in the following table Press EXIT twice to return to the acquisition parameters menu Repeat for the other tube voltages in the table TUBE VOLTAGE X RAY H V CONTROL kV kV 4 3 90 4 10 10 9 70 10 30 20 19 40 20 60 30 29 10 30 90 40 38 80 41 20 50 48 50 51 50 7 Push EXIT twice to stop the acquisition Test complete Spe
65. 5101 0369 TB 8 amp 3 Procedure 7 4 2 5101 0369 TB 8 amp 3 5919 0207 J4 3 2 amp J3 8 9 relay K1 Detector temperature is good but false signal generated due to a bad stack sensor or connection Faulty ECD detector assembly Troubleshooting Measure the detector temperature per procedure Verify by substitution replace if required If desired measure the cooler s resistance off and unplugged to check their condition Internal 2 Q external 1 Q at room temperature This is not a comprehensive test but will identify a major failure ENERGY CALIBRATION FAILS TO EXECUTE SUCCESSFULLY SYSTEM FAILED TO CALIBRATE HARDWARE PROBLEM Cause PRESET COUNT set to non zero value Count rate is too low Fast discriminator requires adjustment Hardware calibration is too far out of adjustment for the system to compensate Short term peak shift caused by one of the following Faulty pulse processor module Faulty ADC board Faulty power supply Unstable detector resolution Remedy Enter ECAL CONFG and set the PRESET COUNT to 0 Raise mA to achieve approximately 5096 dead time Adjust the fast discriminator control for 150 25 counts sec with the X rays off Adjust the pulse processor calibration per procedure Verify by running the RESOLUTION STABILITY test Peak centroid deviation allowed is 3 eV max Verify by substitution replace if required Verify by substitution replace
66. 6 0 and Microsoft Windows version 3 1 or higher Spectrace Instruments QuanX Technical Manual 3 15 Diagnostics ENCLOSURE Type Installation Dimensions not including PC Weight not including PC or vacuum pump Sample Chamber SAFETY Interlocks Radiation Leakage Sound Pressure Level OPERATING ENVIRONMENT Ambient Temperature Relative Humidity Product Description PC monitoring of critical system parameters and system voltages Full remote control capability via modem Molded RIM polyurethane structural foam Indoor only bench top Height 16 2 in 41 1cm top lids closed 33 1 in 84 1cm top lids open Width 28 3 in 71 9cm Depth 23 3 in 59 2cm 27 0 in 68 6cm including clearance for cables and lid 175 200 Ib 80 91kg Approximate weight Actual weight varies based on installed options and LN level 12 0 in 30 5cm wide 16 2 in 41 1cm deep 2 6 in 6 6cm high Maximum sample height is 2 0 in 5 1cm high Implemented for both lids the presence of the X ray tube and detector the enclosure cover and the X RAY ON warning sign operation Fail safe circuit design Dual interlocks on sample chamber lid with separate circuits and mechanical actuators Primary sample chamber interlock uses a positive break EI type switch Less than 0 25 mR hr at 2 inch distance from any surface Less than 60 dbA at 1 meter from any surface LN model 32 to 93 F 0
67. 800 Livetime 300 sec Preset count Ok Max energy 20keV Atmosphere Air Warmup Osec SPECTRUM PROCESSING SAVE ON DISK Ref file no 800 Spectrum Elements of int be Ph Intensities File number Results Ext program Spectrum processing setup SPECTRUM PROCESSING 1 FE NET ROI lt 6120 6660 EV gt 2 PB NET ROI 10120 10860 EV Count rate range setup AMP COUNT RATE MEDIUM Spectrace Instruments QuanX Technical Manual 7 43 Test and Adjustment Procedures 3 Return to the procedure menu and RUN the OIL MINIMUM DETECTION LIMITS test enter 1 for the number of unknowns The dead time should be approximately 50 If not press ACQU MENU amp ACQU PARM and adjust the tube current 1 The system automatically runs spectrum processing and prints out peak and background intensities Calculate the MDL for Fe and Pb using the following formula 3X Csa X al Inn MDL ee peak where ad concentration in the standard ppm 100 for Conostan S 12 Ipeak peak intensity Ibkgna background intensity 1 Verify that the MDL values are equal or less than LN Fe3 0ppm ECD Fe7 0 ppm Pb 5 0 ppm Pb 5 0 ppm Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 44 7 20 Voltage and Current Steps Scope and purpose To verify that the X ray generator responds correctly to voltage and current commands Test equipment Copper sample Test conditions Procedure 7 7 X ray Po
68. DC power supplies e X ray high voltage power supply In addition the high voltages used to drive the detector bias and the ECD ion pump have severe shock potential Preventive measures Disconnect the AC power cord before working on electrical circuits WARNING The ion pump power supply system contains a battery backup and will continue to generate high voltage with the AC power cord disconnected Emergency measures When working on a live circuit have someone stand by clear of the equipment ready to provide assistance If an accident has occurs this person should 1 Immediately and carefully disconnect the power so as to cut off the electric current passing through the victim 1 Not touch the victim until AFTER the power is off Spectrace Instruments QuanX Technical Manual 2 7 Safety 2 4 Poisoning Hazard Beryllium Window WARNING Nature of the hazard The exit window of the X ray tube and the entrance window of the X ray detector are made of thin 10 mil beryllium foil Beryllium metal is highly toxic Do not touch or otherwise handle the foil Preventive measures The beryllium windows on the X ray tube and detector are extremely fragile and brittle When installing replacing or working around the X ray tube and the detector assemblies proceed with great caution DO NOT touch jar or subject the beryllium windows to mechanical or thermal shock DO NOT expose the beryllium windows to corrosive substances su
69. ENERAL STATUS screen Replace if required If only anode current is bad it could be the tube continue to next causes Verify with HV monitor entry on the GENERAL STATUS screen Replace if required If anode current is 0 measure resistance of tube filament Good 0 1 2 Q bad open If the filament is good tube may still be the problem Replace if required Verify by substitution replace if required Verify by substitution replace if required Measure and adjust per procedure Replace if required Verify by substitution replace if required PREAMP RESET RATE IS TOO HIGH WITH X RAYS OFF CHECK DETECTOR STATUS Cause LN level is low The detector coolers have not been on long enough ECD Remedy Fill the dewar and wait 1 2 hours Allow 2 hours for the detector to reach operating temperature Spectrace Instruments QuanX Technical Manual 10 27 Procedure 7 4 1 5919 0161 J5 pins 2 amp 3 cable side only Procedure 9 3 2 Procedure 9 3 4 Procedure 7 4 1 Procedure 9 3 8 Reference 10 28 Troubleshooting The detector temperature is too high Verify on the ECD STATUS screen detector ECD should be less than 190 K Or measure per procedure If high see Detector temperature is too high Bias supply voltage is too high Verify on the GENERAL STATUS screen Bias supply 1v should be less than 1 05 If high replace the bias supply module Bias voltage selection jumper
70. Figure 3 4 for the location of this board Turn off the instrument power switch Disconnect the signal cable from the front panel of the pulse processor Rh 2 ua Remove the board by pulling out on the two ejection ears located on the top of the board Lift the board out of the card cage 1 Install the replacement board by repeating the previous steps in reverse order Press firmly on the board until it snaps into place 1 Set the GAIN switch to the 1 position 1 Perform the following procedures a 7 2 Fast Discriminator Adjustment b 7 9 Initial Energy Calibration c 7 10 Gain vs Count Rate Range Adjustment check only d 7 3 Energy Calibration e System standardization should be checked before beginning quantitative analysis 9 3 3 Bias Supply Board 1 See Figure 3 4 for the location of this board 1 Turn off the instrument power switch 1 Wait one minute then disconnect the preamplifier and signal cables from the front panel of the module 1 Remove the board by pulling out on the two ejection ears located on the top of the board Lift the board out of the card cage Spectrace Instruments QuanX Technical Manual Component Replacement 9 4 Verify that the replacement board bias voltage selection wire is plugged into the same socket as the old board normally 600V for LN and 300 or 400V for ECD The jumper is a yellow wire located under the metal shield Install the replacement board by repeating
71. Government Printing Office Washington D C 20402 2 1 2 Responsibility for Maintenance The maximum operating voltages and currents or ranges of voltages or currents are set at and established by the factory and should not be altered except as explained in this Company s instructions By exceeding established limitations the effectiveness of the incorporated shielding may be reduced to a point where the penetrating or emergent radiation may exceed safe values If radiation shielding shows chemical or mechanical damage service personnel should be notified immediately to prevent accidental radiation exposure All parts of the equipment particularly interlock switches should be carefully maintained for proper operation Doors and covers should close sufficiently to prevent access before interlock switches close Interlock switches are built into the sample chamber baseplate and the instrument frame These switches should under no circumstances be tampered with and should be maintained in proper operating condition In no case should they be defeated or wired out since failure of automatic high voltage and X ray exposure protection will then result Before changing X ray tubes or making any internal adjustments to the X ray high voltage the equipment must be disconnected from the power supply to insure that no X ray emission can occur Care should be taken to assure that all high voltage condenser charges are removed using an insulated groundin
72. Make sure the helium hose is not kinked Reinstall the detector assembly per procedure Test the operation per Procedure 7 23 Spectrace Instruments QuanX Technical Manual 11 4 Optional Equipment 11 3 R Theta Sample Stage 11 3 1 Description The R Theta stage is used to hold fixed disk media The disk platters are held from the center rather than the edges as in a normal sample tray Sample positioning is fully automated and is under the control of the analysis program RTQUANX Positioning is accomplished by linear front to rear translation and up to 360 rotation See the QuanX Operators manual supplement for more information on the program operation The stage uses two stepping motors one for translation and one for rotation The translation axis uses the drive circuitry normally used for the sample tray rotation The rotation axis uses circuitry included only for optional equipment Each axis has an optical sensor and flag which are used to establish a home reference position The translation axis also includes emergency stop switches which interrupt the motor power if the stage travels beyond its normal operating range A special chamber board ROM chip P N 8140 0129 is required to operate the R Theta stage Also the chamber board switches SW1 and SW2 must be set to the THETA position For constant rotation option remove jumper between pins 7 and 8 of J7 on R Theta stage cable Retain jumper by taping to cable See Figur
73. N Once the acquisition begins press ACQU MENU SYS STAT GEN STAT Wait at least 20 seconds to be sure all the voltages have been updated at least once Check that the X RAY H V MONITOR is at approximately 50 kV and that the X RAY TUBE ANODE CURRENT is at approximately 1 00 mA If they are not the problem must be corrected before continuing with this test Turn the knob of the survey meter to BAT Verify that the meter reads in the green zone If not replace the battery Turn the knob to the x1 position and carefully remove the end cap Very very slowly move the probe around the instrument at a distance of 2 inches 5cm from the surface The probe must be held parallel to the direction from where X rays would be leaving the system Check all surfaces of the instrument Pay special attention to the following areas Gap between the chamber lid and baseplate front and right side All frontal surfaces on the chamber end of the instrument Top of the chamber lid Gap around chamber lid while pulling up on the chamber lid If a meter deflection above 0 2 mR h is observed hold the probe in that location to verify the measurement Vary the probe angle slowly to find the maximum reading Only stable readings are valid it is normal for the meter to jump to about 0 15 mR h occasionally due to background radiation To correct for the model 489 35 probe sensitivity at a tube voltage of 50 kV divide the meter reading by 20 For example
74. OA Program cccoocccoccnonononcnononononnnonononnnnnnn nono nennen enne enne eren 8 3 8 3 2 Command Language Description eene nennen nennen 8 3 8 33 ECHOX Command List i eee em e eerte eco e dee tertie dee 8 4 8 3 4 Error or Other Messages From the Chamber Board 8 10 8 3 3 General Usage Notes oie EES 8 10 8 4 QUANX Service Mode 8 11 Spectrace Instruments QuanX Technical Manual 8 1 Diagnostic Software 8 1 Introduction Diagnostic programs allow the service technician to evaluate the performance of various subsystems of the QuanX This capability makes them useful tools for verifying proper instrument operation as well as malfunctions The system status pages within the QUANX program provide system diagnostics Both pass fail status messages and numerical values for various system parameters such as voltages and temperatures are displayed on these pages By viewing them the technician may quickly spot abnormal conditions Access to these pages is described in the QuanX Operators manual This section describes the test procedure files located on the diagnostic diskette and the ECHOA program The test procedure files contain preset instrument parameters for some of the tests in Section 7 Test and Adjustment Procedures ECHOA is a program which allows various instrument functions to be individually exercised A procedure for installing these programs on the computer s hard disk is also included Operation of the computer may be evalua
75. Procedure 9 3 5 Procedure 9 3 1 None given DISCARD THIS PAGE Spectrace Instruments QuanX Technical Manual DISCARD THIS PAGE 11 Optional Equipment Table of Contents 111 Introduction ld 11 1 11 2 Helium Flash aaa 11 2 lr EG Ee e NO e ey de EE 11 2 1 12 72 Specifications ios ss eite dle ee nte ets oed etate e i sat 11 2 112 3 InstallatiOn tart et eoe Hee egt t Elect t e ett Hone EE lobes 11 3 11 3 R Theta Sample Stage Re ER RE eo de Ee 11 4 11 3 1 Descriptions nene Re eer t esee ean ee iain 11 4 11 4 Y2Theta Sample Stage DE et tet ettet lose isis 11 5 RER e Ce EE 11 5 115 XY Sample Stage eee e Reese ete ce e e HU ete Pee REED 11 6 A SST Descrip OM see Pach ME MD UK E EE 11 6 LE 52 InstallatiOB 2i ettet HR ce me Beacons lesb ase EU Tete ERE ica 11 5 1 11 5 3 Stage Position Calibration eese eene enne ren nre 11 5 4 Spectrace Instruments QuanX Technical Manual Optional Equipment 11 1 11 1 Introduction This section provides an overview of the some of the standard options available on the QuanX Each subsection includes a functional description and an installation guide if applicable Spectrace Instruments QuanX Technical Manual 11 2 Optional Equipment 11 2 Helium Flush 11 2 1 Description The helium flush option is required for light element analysis of liquid samples Because low energy X rays are absorbed by the air in the chamber the air must be removed to perform the analysis With non liquid s
76. ROI gross counts displayed on the upper right corner of the screen 1 Add one washer under each corner of the stage and repeat the previous steps do not change the tube current 1 Continue adding washers one at a time and noting the gross counts The count value should start low achieve a maximum and start dropping as more washers are added The correct stage height is the one with the highest gross counts 1 Install the corresponding number of washers under the stage If the X Y stage is to be removed and reinstalled in the future it is a good idea to glue the washers to the bottom of the stage to avoid losing them 11 5 3 Stage Position Calibration Scope and purpose The purpose of this procedure is to determine positional offset corrections which can be used to eliminate any errors between the actual and theoretical location of the home position x 0 y 0 Note that this calibration is required only if the X Y stage has not been setup at the factory for the specific instrument it is to be used with The positional accuracy of the stage is dependent on the accuracy of the home sensor locations Manually positioning the home sensors to within a few thousandths of an inch is difficult so a means of correcting for the actual home locations is used instead A calibration pin is built into the stage at the design location x 0 230 78 steps y 0 590 118 steps The actual location of the calibration pin is measured by using the T
77. Remove the four screws holding the board in place Disconnect the cable from the board Install the replacement board and cover by repeating the previous steps in reverse order Verify that the lead lining in the front of the lid is as close against the casting as possible This is important to prevent an electrical short circuit to the back of the board Start an acquisition If the light fails to illuminate or if the computer gives a warning light related error message try starting the acquisition with the outer cover pulled forward or lifted slightly to determine if the lead is shorting to the board Spectrace Instruments QuanX Technical Manual 9 5 Component Replacement 9 3 6 X ray Control Board 1 See Figure 3 2 for the location of this board 1 Turn off the instrument power switch 1 For ECD systems disconnect the instrument power cord This is required to remove all power from the board Remove the four rear panel screws which hold the enclosure cover in place Remove the enclosure cover by grasping it on the bottom of each side and sliding it directly forward 1 Disconnect all the cables from the board Remove the screws holding the board in place remove the board 1 Verify that the kV selection switch on the replacement board is set as on the old board SOKV 1 Install the replacement board by repeating the previous steps in reverse order Each connector is unique but some can be installed one pin off make sure
78. SPECTRAC VDIDY010 SYS R DEVICE C SPECTRAC VDIPRGRA SYS R DEVICEHIGH C SPECTRAC VDI SYS DEVICEHIGH C DOS ANSI SYS BREAK ON FILES 40 Notes 1 HIMEM SYS is a memory manager for upper memory 1 EMM386 EXE provides access to the upper memory area NOEMS restricts high memory for use as extended memory only not expanded memory X D800 DBFF prevents DOS from using the memory block specified This is required to reserve space for the Spectrace Instruments ADC Interface Board Note that the address must be entered in a 4 digit format Simply drop the last digit from the address listed in TXCONFIG The address block shown D800 to DBFF is the default The actual reserved block will be determined when the ADC interface board is installed Use a word processing program or the DOS EDIT function to modify the addresses in this file See the instructions for installing the ADC interface board for more information 1 Instructs DOS to load itself into high memory Graphics driver for EGA displays used in the QUANX analysis program Do not attempt to load this driver high 1 Graphics driver for the IBM Proprinter Do not attempt to load this driver high 1 VDI controller driver This driver may be loaded high 1 Screen and keyboard device driver 1 System environment setting 1 System environment setting The order that some of the CONFIG SYS commands are entered in the file is critical Any additional commands
79. Set the switch to the 1 position to ve E Fast discriminator requires Adjust the fast discriminator control for 150 adjustment 25 counts sec with the X rays off Spectrace Instruments QuanX Technical Manual Procedure 7 24 Procedure 9 3 3 Procedure 9 6 Reference Procedure 7 2 Procedure 7 12 Procedure 7 12 Procedure 7 15 Reference Procedure 7 2 System requires energy calibration Problem with the X ray detector Check system status X rays off for the following Preamp reset rate is above 1 reset per 2 seconds LN or 10 resets per second ECD Detector temperature is above 190 ECD Ion pump current is above 20 ECD Detector bias voltage is low Problem in the signal processing electronics due to Faulty pulse processor module Faulty detector bias supply module Faulty ADC board Detector body not isolated from ground Electrical noise pickup caused by Ion pump power supply ECD Troubleshooting 10 29 Run energy calibration zero width and Procedure 7 3 resolution measurements are only valid when the system is in calibration See Preamp reset rate is too high See Detector temperature is too high See Jon pump current is high Check the GENERAL STATUS screen bias supply 1V Should be greater than 0 95 Quick check disconnect the small cable between the bias supply output and the pulse processor input The zero width should be approximate
80. Technical Manual 4 5 Theory of Operation 4 4 Safety Interlock Circuit Refer to drawing number 0110 0632 SAFETY INTERLOCK CIRCUIT for a block diagram of the interlock circuit The QUANX BLOCK DIAGRAM drawing 0150 0112 gives the part numbers of the various boards and cables involved Safety Features The safety features implemented by the interlock circuit provide protection against the X rays being turned on when a potentially unsafe condition exists In particular the interlocks provide the following features e All interlocks must be closed for the X rays to turn on If any of the interlocks is opened the X rays are turned off immediately e The X RAYS ON warning light must be on for the X rays to turn on e Tf the interlock circuit is broken the X rays do not turn on again until the interlocks are closed and the analysis sequence is reinitiated by the operator e The current that powers the X ray high voltage power supply flows through most of the interlock circuit Thus if the circuit is broken at any one of the interlocks there is no power to the X ray tube regardless of the status of the logic circuits monitoring the interlock condition e The circuit is designed so that failure of any of the electrical components can only cause the X rays to turn off not to turn on e Every time the sample chamber lid is opened its interlock switch is tested for proper operation by a local microprocessor e The sample chamber lid h
81. Technical Manual Energy Dispersive X ray Fluorescence Analyzer Thermo NORAN Part Number 0120 0041 First Printing June 1996 Revision F Date April 7 1999 Copyright 2001 Thermo NORAN Inc Printed in the United States of America All rights reserved No part of this document may be reproduced or copied in any form without the written permission of Spectrace Instruments Information in this document is subject to change without notice All trademarks are the property of their respective companies Thermo NORAN Inc 2551 W Beltline Hwy Middleton WI 53562 Customer Support 800 495 3839 or 650 562 2500 Outside US and Canada Email supportOthermonoran com Web www thermonoran com Table of Contents General Information Spectrace Instruments QuanX Technical Manual EW oe eene EE 1 1 1 2Scope of the Manual nce et e e EEN 1 2 L3 Reterence Docurnents cttm eet enitn bet ieget ipe esa bee po eee 1 3 L4 Service and EE 1 4 Safety 2 TiIntroduction eases ttti eue etu ettet oett tette 2 1 2 2 Radiation Hazard X Tay S ee nage e ed EEN EEN 2 5 2 3 Electrical Shock Hazard High Voltage essere nennen 2 6 2 4 Poisoning Hazard Beryllium WindoW eese enne 2 7 2 5 Cryogen Burn Hazard Liquid Nitrogen sese 2 8 2 6 Asphyxiation Hazard Cryogen Boil Off cocooocconnccnocanocanoconocnnonncnnncon ccoo nono nocnoconecnnaccnnacns 2 9 Product Description 3 L Introductio
82. Troubleshooting 10 11 10 4 Troubleshooting Chart 10 4 1 Introduction The following troubleshooting chart is intended for use by a service technician The chart is alphabetized by failure symptom with any related error messages listed in italics just below the symptom An index of all the symptoms error messages and key words precedes the troubleshooting chart This allows the reader to scan the available entries and quickly locate items of interest Each failure symptom is followed by a cause remedy and reference chart These charts have the following features e The charts are arranged with those causes listed first which occur most often or are easiest to verify e The causes and remedies are presented in a logical sequence to assist the troubleshooting effort The instructions at any given level assume that the previous causes have been investigated and found to not apply It is important that the technician follow the sequence as presented e The reference column refers the technician to the appropriate location in the system documentation for more information Troubleshooting aids such as the schematic number signal name and connector pin numbers guide the technician to a logical starting point for the troubleshooting effort Also referenced are specific procedures documented elsewhere in the manual which are used to carry out the recommended operations A moderate level of technical ability and familiarity with the system is a
83. UTOEXEC BAK files into the SYS and BAT versions respectively Reboot the computer by pressing the CTRL ALT DEL keys simultaneously Run the Spectrace Instruments configuration program TXCONFIG to configure the software for the particular hardware options installed in the QuanX system Refer to the QuanX operators manual for more information on TXCONFIG To run the program type C gt txconfig and select QuanX from the model list Normally the only entries which may need modification are the detector type ECD or LN and the number of sample tray positions Press the space bar to step through the available options for each item Procedure Using UPDATE to install a new version The UPDATE program will copy all the required files from the release diskettes onto the hard disk It will also copy new versions of the AUTOEXEC BAT and CONFIG SYS as INSTALL does This applies to the new install discs that include the file TSRFont com Note Pressing ENTER return is implied for each of the following commands Also the notation C gt is used to indicate the DOS prompt and is not to by typed when entering DOS commands 1 Insert the master diskette in drive A and type C gt a update 1 Follow the on screen instructions as required 1 Reboot the computer by pressing the CTRL ALT DEL keys simultaneously 5 5 2 DOS Operating System Configuration This section discusses the settings required to establish an environment in which th
84. X Technical Manual 7 41 Test and Adjustment Procedures 3 Verify that the ratio percent for each element is 0 05 or less Verify that the ratio percent for R2 is 0 30 or less for ECD systems This parameter is not specified for LN systems NOTE If the result exceeds this value clean the surface of the test sample with a solvent and repeat the test Any contamination of the surface may cause high results Also check that the detector collimator is installed and properly aligned Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 42 7 19 Minimum Detection Limits Scope and purpose To measure the sensitivity of the system when analyzing an oil sample with known concentrations of iron and lead Test equipment Conostan S 12 100 ppm trace elements in oil Test conditions Optional The diagnostic diskette contents has been installed and the QUANX program has the active directory set as C SPECTRAC QTESTLN or C SPECTRAC QTESTECD for an LN or ECD system respectively Procedure 1 Shake the sample cup containing the oil to mix the elements thoroughly Place the sample cup in position 1 1 Select the OIL MINIMUM DETECTION LIMITS test from the procedure menu or set up an acquisition with the following conditions Overall setup ACQUISITION PARAMETERS ANALYSIS TECHNIQUE Tube voltage 22kV Method d No analysis Tube current 0 06 mA 0 12 ECD Mode Run unknowns Filter used Pd medium Std file
85. X rays are off state is detected The second diagnostic function monitors the operation of the primary sample chamber lid interlock switch When the chamber lid is open two signals are generated a lid open signal generated by the switch located on the lid latch assembly and an interlock open signal generated by the primary interlock switch The microprocessor located on the chamber control board continuously monitors the state of these two signals If ever a state exists such that the lid is open and the interlocks are not open an error condition is logged and saved even after the lid is closed again The next time an analysis is attempted an error message is displayed and continued operation of the system is not allowed The third function is a fail safe fallback condition Before the sample chamber is unlocked the chamber board microprocessor reads the CONFIRM signal to check that the X rays are off If the X rays are not off several more attempts are made to turn them off If they are still on the X ray tube power is reduced to zero and then the lid is unlocked Of course the chamber lid interlock switches will also stop the generation of X rays immediately when the lid is opened The operator is notified by the analysis program as described above Spectrace Instruments QuanX Technical Manual 4 7 Theory of Operation 4 5 Electrically Cooled X ray Detector ECD The X ray detector provides the means for sensing fluoresced X r
86. able mode to scan the pin A default XYTABLE file for this purpose is provided with the software or one can be created with a text editor Any difference between the measured location of the pin and its design location is an offset error The XYQUANX program will automatically correct for these offsets but their values must be manually entered The X and Y offsets are entered from the Test Procedures menu The maximum allowed correction is 20 steps for X and 12 steps for Y about 0 06 but typically the corrections will be only a few steps Test equipment 31 mm copper sample Spectrace Instruments QuanX Technical Manual 11 5 Optional Equipment 5 Test conditions The X Y stage the X Y filter wheel collimator X Y detector collimator X Y detector adapter ring if required and X Y chamber control ROM have been installed Optional The diagnostic diskette has been installed and the XYQUANX program has the active directory set as C SPECTRAC QTESTLN or C SPECTRAC QTESTECD for an LN or ECD system respectively Procedure 1 Verify that a file named XYTABLE CP is present in the same directory as XYQUANX EXE This is a text file with approximately 30 positions centered around x 078 steps y 118 steps If there is another file named XYTABLE rename it Now rename XYTABLE CP to XYTABLE There should be no file name extension 1 Start XYQUANXKX Verify energy calibration by running Energy Calibration using the copper s
87. accordingly It supports both North American single 4 x 1 14 3AG fuse or European IEC type single or dual 5 x 20 mm fuses shocksafe fusing requirements Beginning January 1997 all units are shipped with IEC type fuses See the Specifications section for fuse values The vacuum pump power input and fuse is the connection point for the second instrument power cord The vacuum pump power circuit is separate from the instrument power to reduce the required capacity of an uninterruptable power supply or power conditioner if one is used The connection is made via a standard IEC 320 inlet The inlet module has UL CSA and VDE safety agency approvals and is rated for line voltages of 115 or 230 VAC The shocksafe fuse drawer also accepts either North American or IEC type fuses Beginning January 1997 all units are shipped with IEC type fuses See the Specifications section for fuse values The X RAY ON warning light cable powers the display board located in the sample chamber lid This cable must be connected before the instrument will turn on the X ray source The AC distribution box assembly houses most of the AC wiring in the instrument It is a closed grounded metal box It is the connection point for all external and internal AC line voltage cables It also houses a line filter and a solid state relay for vacuum pump control The RS 232 port is a DB9M connector used to connect the chamber control board to the PC COMI port The external bat
88. ace Customer Service for instructions The sample spinner drive assembly optional used together with the special 10 position sample tray rotates the sample during spectral analysis Rotation is used on rough or odd shaped samples because the analysis results change depending on how the sample is placed in the tray By rotating during analysis the variances are averaged out The drive assembly uses a step motor which is controlled by the chamber control board located in the card cage The assembly may be easily removed or installed as a single unit The detector collimator limits the detector s field of view reducing the incidence of unwanted X rays The detector beryllium window is located just inside the collimator opening CAUTION The beryllium window is extremely fragile and can be broken by the lightest touch Never put anything down the collimator shaft or touch this window in any way If the window becomes contaminated contact Spectrace Customer Service for instructions The LN detector assembly includes the liquid nitrogen dewar the Si Li detector crystal the preamplifier and the beryllium window It converts the X rays emitted and scattered by the sample into electrical pulses These pulses are amplified by the preamp before transmission to the pulse processor board The LN dewar is a double wall vessel with super insulation and high vacuum in the space between the walls The Si Li crystal is mounted to a cold finger extending from
89. acquisition was stopped because the X ray detector heat sink temperature is high Cause Detector heat sink overheated due to low or no air flow Technical reference ACQ ABORTED ION PUMP IS OFF Remed Check that nothing is blocking the vent openings on the left side of the instrument See the troubleshooting chart in the next section See schematic 5919 0207 ECD control board signal HEAT SINK OK The acquisition was stopped because the X ray detector ion pump is off CAUTION Instrument damage may occur if the ion pump is off longer than 3 hours Cause Low or failed 12 volt power source for detector ion pump power supply Remed See the troubleshooting chart in the next section Spectrace Instruments QuanX Technical Manual Troubleshooting 10 5 Technical reference See schematic 5919 0207 ECD control board signal ION PUMP ON ACQ ABORTED STABILIZER LOST ZERO PEAK The system is not able to correct for zero shifts in the energy calibration Cause The ADC requires a logic reset Hardware calibration is too far out of adjustment for the system to compensate Hardware failure ACQ ABORTED ZERO DAC AT LIMIT Remed Exit the program cycle the power off and on and resume operation Adjust the hardware calibration per Procedure 7 9 Initial Calibration See the troubleshooting chart in the next section The system is not able to correct for zero shifts in the energy calibration
90. al Manual 7 7 Test and Adjustment Procedures outputB output B O A output A O O adjustment pot Cf fo e e output A Figure 7 4 PS2 Adjustment points dual output version shown black body 5 Ifadjustment of any other supply is required remove the screw securing the power supply tray and slide the tray forward it may not be removed but will travel forward enough to access the adjustments The linear power supplies PS3 amp PS4 have the adjustment pots labeled The smaller switching supply PS1 has a single adjustment pot below its output connector This pot adjusts the 5V output the 12V outputs are slaved to this output and will respond also The 5V setting is most critical 6 To measure the voltages directly on the power supply outputs rather than the at the motherboard connector refer to Table 7 1 Table 7 1 Power supply voltages VOLT METER VOLT METER SUPPLY POSITIVE NEGATIVE VOLTAGE PS1 TB2 10 TB2 8 5 20V 0 05V TB2 4 TB2 3 12 0V 0 5V TB2 1 TB2 2 12 0V 0 5V PS2 output B output B 24 0V 0 2V PS3 out com 12 0V 0 1V Out com 12 0V 0 1V PS4 out com 24 0V 0 2V out com 24 0V 0 2V Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 8 7 4 2 ECD Cooler Power Supply Scope and purpose To adjust and test the 8100 7415 DC power supply used for the ECD internal and external coolers in the QuanX Test equipment
91. all the pins align Perform the following procedures a 7 7 X ray Power Supply Control Board Adjustment check only b 7 20 Voltage and Current Steps c 7 12 Stability 9 3 7 ECD Control Board CAUTION This procedure will cause the ECD ion pump to turn off The procedure should be carried out in 30 minutes or less 1 See Figure 3 5 for the location of this board 1 Turn off the instrument power switch and disconnect the instrument power cord This is required to remove all power from the board Remove the four rear panel screws which hold the enclosure cover in place Remove the enclosure cover by grasping it on the bottom of each side and sliding it directly forward Disconnect all the cables from the board Remove the screws holding the board in place remove the board Install the replacement board by repeating the previous steps in reverse order Rh 2 bech Plug in the power cord and turn on the power Tap firmly a few times on the ECD ion pump with a screwdriver handle or similar object to ensure that the ion pump has started See Figure 4 3 for the location of the ion pump 1 Turn on the COOLER switch located on the board All the LEDs near the switch except the EXT COOL ON LED should be on The EXT COOL ON LED should turn on within ten minutes 1 Use the ECD STAT screen to check that the voltages and temperatures are within the normal range after the coolers have been on for two hours Spectrace
92. am Turn off the power Disconnect and reconnect the cable connections at each end Turn off the power Reseat ADC firmly See the troubleshooting chart in the next section The software detected a printer during boot up but the printer is not on line now Cause The printer is off line The printer is disconnected Remed Put the printer on line Connect the printer or exit and restart the analysis program with the printer disconnected DEAD TIME TOO HIGH CHANGE PARAMETERS The dead time is beyond the normal operating range Cause The X ray tube voltage or current is set too high Improper filter selected Fast discriminator requires adjustment Wrong pulse processor count rate range selected Hardware failure Remed Lower the kV and or mA settings and restart the acquisition Select a thicker filter Adjust to 150425 with X rays off see Procedure 7 2 Select a higher count rate range See the troubleshooting chart in the next section Spectrace Instruments QuanX Technical Manual Troubleshooting Chamber failed to respond 10 7 The computer is not able to communicate with the chamber control board Cause RS 232 serial communications connector is loose or disconnected from the computer Chamber control board requires a logic reset The board is locked up attempting to locate the sample tray home position Chamber control board not inserted correctly in the card cage
93. ample 1 Select the Manual Position Calibration test from the procedure menu and press SETUP or set up the following conditions in the Setup menu P procedure number from the Procedure menu Overall setup using the HIGH count rate range ACQUISITION PARAMETERS ANALYSIS TECHNIQUE Tube voltage 25kV Method No Analysis Tube current 0 50 mA ECD Mode Run unknowns Filter used Cellulose Std File P00 Livetime 25sec Preset count Ok Max energy 20keV Atmosphere Air Warm up Do Ssec SPECTRUM PROCESSING SAVE ON DISK Ref file no P00 Spectrum Elements of int CU Intensities File number Results Ext program Spectrum processing setup SPECTRUM PROCESSING 1 CU GROSS ROI lt 7900 8160 EV gt 3 Set the initial positional offset corrections to zero The offset corrections can be read and changed from the Test Procedure menu This menu is reached from the Setup menu by pressing F4 then F5 Push F3 for the x position correction and F4 for y position correction Spectrace Instruments QuanX Technical Manual Optional Equipment 11 5 6 Go to the Setup menu and select XY STAGE F7 Select TABLE mode and return to the top level Procedure menu Press RUN and then ENTER when the first sample name appears The dead time should be between 30 and 40 at some point during the run If not repeat the run with the tube current adjusted accordingly The peak copper counts should be printed after each
94. amples the chamber is evacuated with a vacuum pump Since liquid samples will vaporize in a vacuum the air is displaced using helium gas See Figure 11 1 for an illustration of the manifold The hardware consists of a manifold with a pressure regulator pressure switch and two solenoid valves mounted to it A hose is attached between the manifold and the sample chamber wall to carry the helium The two valves are used to provide dual flow rates When an acquisition is started a large volume of air must be displaced from the sample chamber A two minute high flow or purge cycle is initiated by the analysis program After the two minute period the high flow valve turns off and the low flow valve turns on Only a small flow is required during the analysis to maintain the chamber environment The pressure regulator is used to provide a known stable pressure inside the instrument regardless of the helium inlet pressure within the specified limits The flow rates are then set by the manifold orifices The pressure switch is used to detect a low flow condition which would adversely affect the analysis performance If the helium tank runs out the analysis program will not allow an analysis to begin or will stop an analysis already in progress and display a warning message 11 2 2 Specifications Inlet fitting 4 inch hose barb Inlet pressure 15 to 65 psig 103 448 kPa Consumption flow rate high flow cycle 15 scfh 425 1 h low flow cycl
95. and press RUN The dead time should be approximately 50 If not press ACQU MENU amp ACQU PARM and adjust the tube current press EXIT Allow the test to run for a minimum of 8 hours 1 The test results report the total system error instability This error is a combination of the instrument error and counting statistics To evaluate the instrument error alone use the following formula 10 000 N Instrument error RSD ES where N number of total or peak counts from the printout RSD cz total or peak deviation percentage e g total 2 0 1296 use 0 12 for RSD 1 Verify that the instrument error is 0 20 or less for TOTAL counts and 0 23 or less for PEAK counts Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 24 1 The other test values should be as follows Parameter Value Deviation during test FWHM resolution 215eV typical 5eV max Peak Centroid 8041 typical 3eV max Interpreting the test results If the TOTAL and PEAK stability is within specification no further interpretation is required Instrument stability precision may be divided into two components X ray source stability and X ray detection stability A problem in either area will result in poor analysis precision This test is designed to differentiate between the two In general X ray source instability will affect the entire spectrum equally For example if the X ray tube output drops by 1 all a
96. are to help evaluate the gain error Adjust the FINE GAIN pot so that the error is less than 10 with the gain DAC set forced at zero Note If the pot is over adjusted in one direction there will be some backlash when adjusted in the reverse direction It is best to continue turning past this point in the same direction before turning back in the opposite direction 1 Repeat the steps until the error is less than 10 when the gain DAC is forced to zero and the system automatically halts calibration The program halts energy calibration automatically when the error is very small less than 1 Note If the system halts acquisition before the gain pot is adjusted restart the energy calibration Calibration of medium count rate range 13 Restart the energy calibration acquisition by pressing ENRGY CALIB 1 Press ACQU MENU SYS STAT COUNT RATE and type M to set the pulse processor to the medium range Press EXIT 1 Make sure that the dead time is approximately 50 If necessary press ACQU PARM and adjust the tube current 1 Follow steps 7 12 as for calibration of high count rate range except use R102 instead of the FINE pot located just behind the PA RESET light on the front of the pulse processor PCB This pot may be accessed through the lower hole in the metal cover attached to the left side of the board Note R102 is much more sensitive than the FINE adjustment pot and has worse backlash Calibration of low count r
97. arked on the connectors Dress the cables inside the chamber for no interference with the stage Slowly lower the right side of the stage until it is resting flat on the baseplate being careful not to pinch any cables Verify there is no interference with cables by moving the stage over its full Y axis stroke forward backward Install the two 6 32 x 1 2 flat head screws item 7 first on the left side of the stage This aligns the stage with the baseplate center line Verify again that the stage is resting flat on the baseplate and that there is no interference Install the two remaining screws 416 32 x 4 socket head on the right side Manually slide the stage forward and backward and left and right It should slide smoothly without binding Do not power up the instrument until the chamber control board ROM has been changed 11 5 2 3 Changing the Chamber Control Board ROM Reference section 9 3 in the Technical Manual 1 1 Rh m bech See Figure 3 4 in the Technical Manual for the location of this board Turn off the instrument power switch For ECD systems disconnect the instrument power cord This is required to remove all power from the chamber board socket Remove the board by pulling out on the two ejection ears located on the top of the board Lift the board out of the card cage If a replacement board with the X Y Stage ROM already installed is available go to step 8 Otherwise continue Use a stati
98. as fragile as the detector window but caution must still be exercised 1 For particulate matter removal without removing the X ray tube a small vacuum may be used Remove the metal plate covering the sample chamber components Remove the two socket head screws holding the filter wheel assembly in place Move the assembly aside it is not necessary to disconnect its cables Spectrace Instruments QuanX Technical Manual 7 53 Test and Adjustment Procedures 1 Lower the vacuum nozzle to the X ray tube collimator opening Do not allow the vacuum nozzle to seal completely against the collimator surface 1 If vacuuming is not sufficient to clean the window remove the X ray tube by following the procedure in Section 9 Component Replacement 1 Remove the collimator from the tube The collimator is not fastened on it may have remained in the chamber wall when the tube was removed 1 Follow the procedure outlined above for the detector window Hold the tube with the window down so the liquid drains out 1 Replace the tube and other components Spectrace Instruments QuanX Technical Manual 8 Diagnostic Software Table of Contents 8 1 Introduction 8 1 8 2 Diagnostic Disk Installation 000 ceeceseeeseeceseeeseeeseeseneeececcneeseeeecneseaeecaeecaaecaaecsaeseaaeenaes 8 2 8 3 RCHOA PROGRAM eee t ret pee ete e HE Ge ED eee ee E EP pla ee nete aee 8 3 8 3 1 Starting the ECH
99. as opened 10 33 10 34 e problem lid is open 10 34 x rays not on hardware problem warning light is off 10 24 10 33 10 34 x rays not on hardware problem warning light current is high 10 34 x rays turn off during a x rays will not turn on Z zero dac at limit 10 14 n acquisition 10 33 10 34 zero width is high 10 29 Spectrace Instruments QuanX Technical Manual confirm signal failure 10 24 10 33 10 34 10 13 10 14 Troubleshooting ACQ ABORTED ION PUMP IS OFF Cause Low or failed 12v power ECD control supply on board Faulty ECD control board generated false signal Remedy Measure voltage to confirm Replace ECD control board Verify and replace the board ACQ ABORTED STABILIZER LOST ZERO PEAK Cause The hardware zero setting is too far out of adjustment for the ADC to compensate PS1 5 V power supply is low Faulty pulse processor module Faulty ADC board Remedy Adjust the zero control on the pulse processor module until the zero DAC is below 200 Measure per procedure or measure the voltage across the small capacitor above the ADC interface cable connector on the ADC Must be greater than 4 95 V Verify by substitution replace if required Verify by substitution replace if required ACQ ABORTED ZERO DAC AT LIMIT Cause The hardware zero setting is too far out of adjustment for the ADC to compensate PS1 5 V power supply
100. as two interlock switches with separate circuits and mechanical actuators e The sample chamber lid primary interlock switch uses a Positive Break E design the contacts are forced open by a mechanical drive mechanism rather than by a spring as in a normal switch It also features a bypass resistant actuator which requires a unique geometry actuator key to close the contacts Interlock Circuit The circuit starts with 24 volts at the output of power supply PS2 located on the power supply tray The 24 volts is carried by cable 5101 0273 which connects to the X ray control board schematic 5919 0161 on J2 pin 1 The 24 volts exits the X ray control board on J3 pin 4 and is routed in series through all of the interlock switches and returns on J3 pin 3 The interlock switches are located on the chamber detector and X ray tube ports the sample chamber lid the left cover and the enclosure cover The switch connections are part of cable 5101 0375 The 24V is then passed through a jumper in the X ray tube filament cable connector J5 pins 4 amp 5 to prevent generation of high voltage if the X ray tube is disconnected From there the 24V exits the X ray control board again on J3 pin 2 on its way to the chamber control board schematic 5911 0217 where the X rays on off control is accomplished The signal enters the chamber control board on J1 pin 7 and is named INTERIN It passes through relays K1 and K3 to turn on the X rays K1 is controlled by lo
101. ate range 17 Restart the energy calibration acquisition by pressing ENRGY CALIB 1 Press ACQU MENU SYS STAT COUNT RATE and type L to set the pulse processor to the low range Press EXIT 1 Make sure that the dead time is approximately 50 If necessary press ACQU PARM and adjust the tube current 1 Follow steps 7 12 as for calibration of high count rate range except use R101 instead of the FINE pot located just behind the PA RESET light on the front of the pulse processor PCB This pot may be accessed through the upper hole in the metal cover attached to the left side of the board Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 20 Note R101 is much more sensitive than the FINE adjustment pot and has worse backlash Note After the low range is calibrated recheck the high range If the high range needs to be readjusted then recheck and readjust the medium and low ranges again as well Spectrace Instruments QuanX Technical Manual 7 21 Test and Adjustment Procedures 7 11 Resolution Scope and purpose To verify the operation of the detector and related circuitry Either of two samples may be used manganese or copper Manganese is the industry standard 5 89keV for resolution specification Copper is convenient because it is readily available Test equipment MnO or Cu sample Test conditions The system must be energy calibrated otherwise the resolution results are meaningless
102. autions Routine Procedure 1 Run TXCONFIG to select the appropriate system options On the first menu select the type of system being installed press ENTER and select COMPUTER Atthe COMPUTER PRINTER menu on the MICROCHANNEL OR PC ISA BUS line enter P to choose PC bus The MEMORY ADDRESS USED will be D8000 1 Turn off the power to the computer and install the ADC interface board Turn on the power to the computer a Ifthe system boots up and initializes normally the current address setting will probably work Go to step 4 b Ifthe screen remains blank or does not function properly there is probably an address conflict If during initialization of the system there is an error message related to a hard disk interface or expanded memory this also indicates an step 3 address conflict Go to 3 Below is a list of the choices of memory mapped addresses for the ADC interface board The interface requires a contiguous block of open memory 16K in length Turn off the power set SW1 to one of the values listed in Table 1 turn on the power Return to step 2 Table 1 ADC Interface board address ADDRESS BLOCK USED C0000 C3FFF C4000 C7FFF CC000 CFFFF D0000 D3FFF D4000 D7FFF D8000 DBFFF DC000 DFFFF E0000 E3FFF E4000 E7FFF E8000 EBFFF EC000 EFFFF Notes 1 z Default setting SWITCH SETTING FOR SW 1 OFF 1 2 OFF 1 2 6 OFF 1 2 5 6 OFF 1 2 4 OFF 1 2 4 6 OFF 1 2 4 5 OFF 1 2 4 5 6 OFF 1 2 3 OFF 1 2 3
103. ay photons and converting them to electrical signals The detector assembly consists of a Si Li detector which is the X ray sensing device a vacuum tight housing an ion pump to maintain a good vacuum and thermoelectric coolers to cool the Si Li detector to its operating temperature The Si Li detector shown in Figure 4 2 is made from a high purity silicon crystal A bias voltage is applied to electrical contacts on opposite sides of the crystal to produce an electric field throughout the crystal volume When an X ray photon enters the active region of the detector electron hole pairs are created by the process of photo ionization These mobile charges are collected at the contacts by the action of the electric field which pushes the electrons to the signal contact and the holes to the Schottky barrier contact This collected charge is the sensor s output signal and is connected to the gate of the FET for amplification Since an electron hole pair is produced for each 3 8 eV of photon energy the signal amplitude is proportional the photon energy The guard ring contact which surrounds the signal contact intercepts surface leakage current which would contribute noise to the output signal A set of cascaded thermoelectric coolers is used to cool the Si Li detector to a temperature of 85 C At this temperature noise produced by thermally generated electron hole pairs within the detector is virtually eliminated Thermoelectric coolers are solid s
104. back loop is used When the output exceeds zero volts an LED inside the detector assembly is pulsed on Light striking the FET induces current to flow from its drain to gate This current removes the charge which has accumulated on the gate and resets the output to a negative voltage Si Li DETECTOR X X RAY UV d BIA 1 5 V K RESET CIRCUIT Figure 4 6 Pulsed optical preamplifier and FET Spectrace Instruments QuanX Technical Manual Theory of Operation 4 12 4 8 Chamber Control Board The part number of this board is 5911 0217 and the circuit is shown in schematic no 5919 0217 Overview The chamber control board is responsible for all machine functions some of which include e Monitoring safety interlocks e Communicating with the personal computer e Setting the X ray tube power e Controlling the chamber atmosphere e Driving the stepping motors for the sample tray and filter wheel The board is based on an 8031 microcontroller Communication with the personal computer is by means of a 3 wire RS 232 interface using RxD TxD and GND at 9600 baud no parity 8 data bits and 1 stop bit The program memory is stored in a 64K x 8 EPROM An 8282 octal latch is used to separate the address for the EPROM Two 8255s and a 74L S244 are used to increase the number of I O lines on the board Auto reset In order to ensure that the microcontroller will recover from a random error an automatic reset circuit is used Shoul
105. be current Note If the acquisition parameters must be changed to achieve 5046 dead time wait 20 seconds after making the changes before EXITing in order to allow the zero stabilizer to reach equilibrium 1 Observe the ERR number at the bottom left of your screen This indicates how far off the peak is from where it should be The GAIN DAC shows the amount of correction that the system has calculated is necessary to bring the peak into correct gain adjustment 1 Type CU and press ENTER to display the KLM markers for copper 1 Press ZERO GAIN to reset the gain DAC to zero Now observe the peak and marker locations If the center of the peak is near the K alpha marker turn the FINE adjust pot on the pulse processor to line up the peak and marker as close as possible If the peak is not close to the marker then start with the COARSE gain adjust pot to bring the peak close to the marker then use the FINE pot To move the peak up in energy a negative error reading Spectrace Instruments QuanX Technical Manual 7 19 Test and Adjustment Procedures turn the pot clockwise To move the peak down in energy a positive error reading turn the pot counter clockwise 1 Adjust the peak so that the error is less than 10 with the gain DAC at zero Note When adjusting to correct the error press the ZERO GAIN key as necessary so that gain DAC stays at 0 1 When the peak is as close to the marker as possible by visual inspection use the softw
106. but the chamber control board is reporting that the X rays are off because an interlock has been opened Cause An interlock is open Hardware failure Technical reference Remed Check the left top cover and enclosure cover switches and the mounting switches under the X ray tube and X ray detector See the troubleshooting chart in the next section See schematic 5919 0217 chamber control board signal INTERLOCKS and 0110 0632 safety interlock circuit Spectrace Instruments QuanX Technical Manual 10 10 Troubleshooting X RAYS NOT ON HARDWARE PROBLEM Light On signal failure The X rays should be on but the chamber control board is reporting that the X rays are off because the warning light is not illuminated Cause Warning light cable is not plugged in Hardware failure Technical reference Remed Check that the cable located on the rear panel is properly connected See the troubleshooting chart in the next section See schematic 5919 0217 chamber control board signal LIGHT ON X RAYS NOT ON HARDWARE PROBLEM Warning light current is high A failure in the X RAY ON warning light has been detected X rays can not be generated until the problem is corrected Cause Hardware failure Technical reference Remed See the troubleshooting chart in the next section See schematic 5919 0217 chamber control board signal LIGHT HIGH Spectrace Instruments QuanX Technical Manual
107. by other equipment in the plant Although internal power filters are employed this equipment is sensitive to power line noise These excess power line voltages exist at extremely high frequencies and can occur in nanosecond time periods Both normal mode line to line and common mode line to ground disturbances can cause a variety of problem ranging from intermittent performance degradation to actual component failure Due to modern power supply design moderate voltage variations are tolerated The use of a voltage stabilizer is not generally required nor recommended due to the nature of the switching mode power supplies used The best protection is provided by a low impedance power conditioner filter designed for use with switching power supplies A unit of this type may be ordered as optional equipment Due to the unpredictable and sometimes intermittent nature of power line disturbances diagnosis of a problem can be difficult costly and or cause a serious loss of productive work time Therefore a power line conditioner of the proper type is always a wise addition 5 2 7 Telephone A telephone within reach of the system should be considered a mandatory site requirement Eventually service or applications assistance will be required A telephone at the instrument s location often makes the difference between the quick resolution of a problem or days of downtime because an on site visit is required In addition to verbal support the instrumen
108. c guard or other means to remove any static electricity before touching the ROM IC Note the QuanX ROM location and orientation it is p n 8140 0127B Carefully remove the ROM using a small flat blade screwdriver to alternately pry each end up a small amount at a time Install the X Y Stage ROM p n 8140 0131 being careful not to bend any leads Verify that switches SW1 and SW2 are both set to the THETA position Install the board with the X Y stage ROM pressing firmly until it snaps into place Connect the power cord and turn on the power switch The stage should position itself at the home positions for X left most position and for Y most rearward position Spectrace Instruments QuanX Technical Manual 11 5 Optional Equipment 3 11 5 2 4 Stage Height Adjustment Scope and purpose Note that this adjustment is only required if the X Y stage has not been setup at the factory for the specific instrument it is to be used with Set the height of the X Y Stage to compensate for variations in the x ray spot location and alignment Proper height adjustment maximizes the detected flux and minimizes the sensitivity to stage height variations Test equipment Thin about 0 015 6 flat washers Brass or copper sample Single sample frame support Test conditions The X Y stage with collimators and the X Y stage ROM have been installed Optional The diagnostic diskette has been installed and the XYQUANX program has the active directo
109. cedures 7 6 Interlock Test Scope and purpose To test the operation of the interlock circuit This includes not only the operation of the switches but also that of the chamber board and the lid latch This is a safety related procedure Test equipment None Test conditions Procedure 7 5 Latch Adjustment must have been completed if the latch assembly or primary lid interlock switch were replaced Procedure 1 Remove the main enclosure cover 1 Turn on the system power Close the chamber lid 1 The INTERLOCK DS2 LED on the X ray power supply control board should be off Press in on the actuator of the front cover interlock switch the DS2 LED should light 1 Bypass the front cover interlock switch by pulling out on its actuator shaft DS2 should be on open the left top cover DS2 should turn off 1 Bypass the left top cover interlock switch by pulling up on its actuator shaft DS2 should be on open the chamber lid DS2 should turn off 1 Verify that the LID CLOSED LED on the chamber board is on when the chamber lid is closed and turns off when the lid is opened 1 Close the chamber lid start the QUANX program and start an acquisition Break the front cover interlock by pushing in and releasing its actuator rod The X rays should turn off and the computer should be displaying an open interlock message Bypass the interlock switch again the X rays should not turn back on 1 Restart the acquisition and set the tube vol
110. ch as acid acid vapor such as from caustic samples water water vapor or others substances Protect the surface of the beryllium window by installing a collimator with a protective mylar window attached Exercise caution when handling materials and samples in the vicinity of the beryllium window Any physical contact with the window will almost certainly rupture it even small particles can puncture the beryllium window Emergency measures If breakage of a beryllium window occurs proceed as follows 1 Avoid touching breathing or swallowing the particles and do not allow the particles to come into contact with your skin or clothing 1 Gather all broken pieces and particles immediately using a pair of tweezers or the sticky side of masking tape 1 Handle the beryllium pieces as you would a poison Place them in a sealed unbreakable container labeled CAUTION BERYLLIUM POISON and contact the proper authorities for transport and disposal guidelines If the beryllium particles have come into contact with skin remove them as described above and wash the affected area thoroughly If the beryllium particles have come into contact with clothes remove and discard the particles carefully as described above Wash the clothing thoroughly Check for beryllium particles on the skin as described above Spectrace Instruments QuanX Technical Manual Safety 2 8 2 5 Cryogen Burn Hazard Liquid Nitrogen WARNING Cryogenic liquids and gas
111. chematic Diagrams Some assemblies have both types of drawings for example PC boards The Table of Contents includes both drawing numbers for each item if they exist However the actual drawings are sorted numerically for easy access The Table of Contents is divided into System and Options sections The System section contains drawings common to all models System Schematic 0150 0112 0110 0632 0110 0633 5919 0161 5919 0181 5919 0224 5919 0225 5919 0216 5919 0217 5919 0218 5919 0219 5919 0222 Assembly 9100 4901 8100 7401 8100 7403 8100 7404 8100 7405 8100 7406 8100 7407 8100 7408 8100 7411 8100 7412 8100 7413 8100 7414 8100 7432 8100 7437 5911 0220 5911 0181 5911 0224 5911 0216 5911 0217 5911 0218 5911 0219 5911 0222 Table of Contents Title QuanX Block Diagram Safety Interlock Circuit QuanX Generic Filter Wheel Assembly Power Supplies Assembly SOKV 2mA Power Supply Assembly Card Cage Assembly Latch Assembly AC Distribution Box Vac He Flow Panel Assembly Base Plate Assembly Chamber Lid Assembly PS3 12V Linear Power Supply PS4 24V Linear Power Supply PS2 A amp B 24V Switching Power Supply Single Sample Tray Assembly Voltage Current Control Board ADC Interface Board old ADC Interface Board new ADC Micro Board Distribution Board Chamber Control Board Display Board Mother Board Pulse Processor Board Spectrace Instruments QuanX Technical Manual System Schematic
112. closure The fan speed is variable and is controlled by an external sensor mounted on the front of the card cage When the cooling demand is low such as when the room ambient temperature is low the fan runs slower to reduce noise The fan s output is ducted to an air plenum under the floor of the instrument Cooling air is directed upward through a series of holes in the floor In this way directed spot cooling of critical components and overall enclosure cooling are performed simultaneously The fan is mounted on rubber isolators to prevent vibration of the detector The pulse processor receives the detector preamplifier output signal It provides pulse shaping and other signal conditioning to prepare the signal for conversion in the ADC The controls for GAIN and Spectrace Instruments QuanX Technical Manual 3 7 Product Description ZERO used for initial energy calibration as well as the FAST DISCRIMINATOR threshold adjustment are located here The detector preamp cable connects the detector assembly to the bias supply board This cable carries the detector high voltage bias the detector output signal and several DC voltages The chamber distribution board is a connection point for the motors and sensors located inside the sample chamber One or two depending on options installed cables connect this board to the card cage motherboard via vacuum tight feedthru fittings in the chamber wall The sample tray drive assembly optional drive
113. connect its cable Remove the four screws which attach the detector to the sample chamber baseplate These screws have nylon insulators under them and are accessed from inside the sample chamber DO NOT remove any screws from the detector assembly itself as this will break its vacuum seal Support the detector neck area with one hand while removing the last screw 1 Grasp the dewar and the neck and carefully guide the detector out the end of the instrument Keep an eye on the beryllium end until it clears the chamber area Installation 1 Transfer the o ring from the old unit to the replacement unit if it didn t come with one installed If the o ring is dirty clean it off and reapply a thin coat of vacuum grease Transfer the insulator ring from the old unit to the replacement unit Apply a few spots of vacuum grease to the underside of the insulator ring align the holes in the ring with the flange screw holes and press it into place The grease will hold the ring in place making the final installation easier Normally the replacement unit will have the dewar mounting frame installed If so skip this step If not transfer the frame from the old to the new dewar The insulating nylon shoulder washers must be installed in the same way so that the frame is electrically isolated from the dewar Spectrace Instruments QuanX Technical Manual 9 15 Component Replacement 1 Transfer the collimator from the old unit to the replacement unit
114. contains an operational mode useful to the service technician The instrument contains a number of signals which the computer monitors during normal operation If an error condition is detected the program will respond accordingly quite often discontinuing all operations Occasionally the service technician will wish to intentionally operate the system in such a way that an error signal is generated By placing the program in SERVICE MODE the error will be ignored The following error conditions are ignored when operating in SERVICE MODE e No counts in the X ray spectrum e ECD coolers are off future software release SERVICE MODE does not disable the X ray interlock monitor One new feature is added while running in this mode The operator may choose to turn off the automatic zero stabilization feature in the ADC This is useful for diagnosing energy calibration drifts or for reducing the erratic operation which sometimes occurs when the ADC attempts to compensate for a failure in another component A new function key labeled ZSTAB OFF is presented on the DETECTOR STATUS screen After pushing this key the message Monitor only will appear on the screen The zero DAC is held at its present value and the zero offset may be used to monitor the zero drift To resume automatic zero stabilization press the ZSTAB ON function key To activate the SERVICE MODE a switch in the TXCONFIG program is set Run TXCONFIG directly from the DOS prompt by typi
115. control Execute command Set RTheta rotation position 0129 ROM only Enable disable Interlock Interrupt Name Vacuum status Sample spinner status X ray tube high voltage X ray tube current Helium low flow status Diagnostic Software Usage Error Response CRO CRF CSxx MAX CSxxx MAX CTO ELID CTF EPO CYxxx MAX CZO CZF Usage Respons e AAO AAF AAW ABO ABF Axx Axx ADO ADF Usage Description Turn vent valve ON Turn vent valve OFF Set tray to pos x 1 x 0 19 Set linear position to xxx 0 00694 inches forward from home 000 home Lock chamber lid Unlock chamber lid Executes all C_ commands since last CX Set rotation position to xxx degrees 000 home Enable interrupt Disable interrupt Response Description Pump ON amp chamber vacuum good Vacuum pump OFF Vacuum pump ON amp chamber vacuum not good WAITING for vacuum Sample spinner ON Sample spinner OFF Tube voltage xx kV Tube current 0 xx x2 mA Low flow valve is ON Low flow valve is OFF Spectrace Instruments QuanX Technical Manual Comman d query QE QEA QEB QEC QEH QEI QEP QF QG QH QI Name All ECD status ECD installed status ECD external cooler voltage status base drive ECD coolers status ECD heat sink temperature status ECD ion pump current status ECD ion pump power status Filter position LN level status or ECD detector
116. cted to the vacuum pump power inlet the instrument does not convert this voltage This outlet is a switched outlet under the control of the analysis software It is fused as previously described The computer power convenience outlets may be used to operate the PC They are standard NEMA 5 15R receptacles The voltage present at these outlets is identical to the AC line voltage connected to the instrument power inlet the instrument does not convert this voltage The outlets are not switched or fused The maximum power rating for all three combined is 800 watts WARNING AC line voltage is always present at the convenience outlets when the instrument power cord is plugged in even when the instrument power switch is off The AC line voltage selection switches configure the instrument for operation on 115 or 230 VAC Both switches must be set to the appropriate setting before the power cord is plugged in CAUTION Failure to select the correct AC line voltage switch setting may cause instrument damage Spectrace Instruments QuanX Technical Manual 3 3 Specifications PERFORMANCE Elements Determined Concentration Range Accuracy Precision Calibration SAMPLE PHYSICAL PROPERTIES Type Size EXCITATION X ray Optics X ray Tube X ray Generator X ray Stability Filters Filter Collimators optional Chamber Environment Product Description 3 12 Sodium through uranium Parts per million to percent
117. ction device on the QuanX Therefore ensure that the power cord is easily accessible at all times A Spectrace Instruments QuanX Technical Manual 2 5 Safety 2 2 Radiation Hazard X rays WARNING X rays are injurious to health Never energize the X ray tube if the safety features of the instrument have been damaged or defeated Nature of the hazard Although this equipment is safe to use and is designed to prevent accidental exposure any X ray producing equipment can be dangerous to both the operator and persons in the immediate vicinity unless safety precautions are strictly observed Exposure to X rays is injurious to health Therefore users should avoid exposure not only to the direct beam but also to secondary or scatted radiation which occurs when an X ray beam strikes or has passed through any material Preventive measures It is especially important that users and technicians not try to circumvent or defeat the safety features built into the instrument They should always be aware that the X ray beam can constitute a distinct hazard if not employed in strict accordance with instructions Human beings have no senses for X ray Therefore X ray measuring instruments such as low energy X ray Geiger counters must be used to detect X ray emission or radiation leakage When test or troubleshooting procedures call for interlocks to be defeated temporarily always disconnect the X ray tube from the high voltage power supply T
118. ctional system The power has been on for at least two hours Test equipment Universal adjustment tool tweeker or small flat blade screwdriver Test procedure 1 Start the QUANX program Press SETUP and SYS STAT 1 Read the FAST DISC RATE value This number changes about once per second and normally has a range of about 50 counts 150 25 1 If the average rate is not between 125 175 adjust the FAST DISC pot on the pulse processor board clockwise to decrease the count rate counterclockwise to increase to obtain an average value of approximately 150 Note that the X rays should have been off for at least 10 minutes and the power should have been on for at least two hours Figure 7 1 shows the locations of the adjustment pot INPUT be GAIN 4 0 COARSE CALIBRATE o FINE Q FD OUTPUT HIGH DT PA RESET 0 FAST DISC o ZERO PULSE PROCESSOR MODULE Figure 7 1 Pulse processor adjustment pots and indicator lights Spectrace Instruments QuanX Technical Manual 7 3 Test and Adjustment Procedures 7 3 Energy Calibration Scope and purpose To adjust the pulse processor gain so that detected X rays appear at the correct energy This is an automated process which should be executed daily Test conditions For the computer to locate the peaks and automatically adjust the system gain the hardware gain adjustment must be close to correct This adjustment is explained in Procedure 7 9 Initial Ener
119. ctors and the two solenoid power wires Remove the two screws holding the latch assembly to the chamber baseplate Install the replacement assembly Reconnect the solenoid wires no polarity and the two switch connectors For safety considerations it is important that the connectors are connected to the correct switch The violet black cable connects to the front most lock sense switch the brown black cable connects to the lid closed sense switch Adjust the latch according to Procedure 7 5 Ignore the portions of the procedure regarding the primary lid interlock switch Spectrace Instruments QuanX Technical Manual Component Replacement 9 20 9 7 5 Vacuum Pump Power Relay 1 EO REO m E E See Figure 3 6 for the location of the AC distribution box assembly The relay is located inside this box Turn off the instrument power Disconnect the instrument and vacuum inlet power cords Remove the four real panel screws holding the AC distribution box to the rear panel Slide the box out Several screw heads and wires may catch as it is pulled out but it does fit Remove the box cover panel The solid state relay is mounted to the wall Note the electrical connections before detaching any wires Remove and replace the relay Apply heat conductive paste to the new relay before installation If none is available use the paste from the old relay Reassemble the parts by following the previous steps in reverse order Spectrace In
120. ctrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 46 7 21 Chamber Vacuum Test Scope and purpose To test and adjust the sample chamber vacuum subsystem The test includes setting the vacuum sensor trip point and measuring the chamber pump down speed Test equipment 200 liter per minute vacuum pump Varian 801 vacuum thermocouple meter or equivalent Vacuum hose tee with a Varian TYPE 0531 or equivalent thermocouple gauge installed Test conditions No liquid samples may be in the sample chamber Procedure 1 Install the tee in line with the vacuum pump hose Connect the vacuum pump hose and power cord to the QuanX rear panel 1 Connect the meter to the thermocouple mounted in the tee 1 Open the left top cover and bypass its interlock switch by pulling up on its actuator 1 Set SW3 the VAC SET switch on the chamber control board as follows 1 5 ON down 6 8 OFF up The VACUUM OK LED on the left end of the chamber control board should be off 1 Start an acquisition with vacuum atmosphere zero seconds live time and any other conditions The pump should turn on and the computer should be displaying a Waiting for vacuum message 1 Watch the vacuum gauge meter and the VACUUM OK LED note the pressure when the LED turns on If the pressure is between 750 and 1000 millitorr microns go on to step 8 1 If the trip point pressure wasn t correct change the setting on SW3 one segment at a time an
121. d Measure and adjust per procedure Replace if required See Resolution is poor Spectrace Instruments QuanX Technical Manual Procedure 7 25 Procedure 9 6 Reference Procedure 7 12 Procedure 9 4 1 Procedure 9 3 6 Procedure 9 7 1 Procedure 7 12 Procedure 9 3 2 Procedure 9 3 4 Procedure 7 4 1 X RAYS DO NOT TURN OFF Troubleshooting X RAYS NOT OFF HARDWARE PROBLEM CONFIRM SIGNAL FAILURE Cause Faulty chamber control board Remed Replace chamber control board X RAYS TURN OFF DURING AN ACQUISITION X RAYS NOT ON HARDWARE PROBLEM CONFIRM SIGNAL FAILURE X RAYS NOT ON HARDWARE PROBLEM INTERLOCK HAS OPENED X RAYS NOT ON HARDWARE PROBLEM WARNING LIGHT IS NOT ON Cause Interlock opened High voltage arcing X RAYS WILL NOT TURN ON Remedy See the appropriate section of X rays will not turn on See High voltage arcing X RAYS NOT ON HARDWARE PROBLEM CONFIRM SIGNAL FAILURE X RAYS NOT ON HARDWARE PROBLEM INTERLOCK HAS OPENED X RAYS NOT ON HARDWARE PROBLEM LID IS OPEN X RAYS NOT ON HARDWARE PROBLEM WARNING LIGHT CURRENT IS HIGH X RAYS NOT ON HARDWARE PROBLEM WARNING LIGHT IS OFF Cause Symptom The X ray warning light is off it did not even flash on and the computer says it is off The warning light connector is unplugged Faulty display board Faulty chamber control board Symptom The X ray warnin
122. d repeat the test Setting more segments ON down causes the trip point to occur sooner higher pressure and setting more segments OFF up causes the trip point to occur later lower pressure 1 Stop the acquisition and allow the chamber to vent Open and close the chamber lid 1 Restart the acquisition note the time The chamber must begin pumping by itself without pressing on the lid If it doesn t the chamber lid or baseplate must be adjusted 1 Note the time when the VACUUM OK LED turns on 1 Verify that the VACUUM OK LED turned on in 90 seconds or less Verify that the pressure is less than 500 millitorr within 10 minutes Spectrace Instruments QuanX Technical Manual 7 47 Test and Adjustment Procedures 7 22 System Status Voltages Scope and purpose To verify that all the system status voltages are reading within the normal range This not only checks several instrument parameters it also tests the voltage measurement circuit Test equipment Printer Test conditions Complete fully functional system Procedure 1 Start an acquisition with the following parameters Tube voltage 25 kV Tube current 1 98 mA Filter Cu thin Livetime 0 sec Preset count 0 Max energy 20 keV Atmosphere Air Warmup 0 sec 1 Press ACQU MENU SYS STAT and GEN STAT 1 Wait 30 seconds to allow each value to be updated twice Verify that all the values are within the range specified on the screen The X RAY H V CONTROL and X RAY H
123. d an error cause the auto reset circuit to be serviced too often or not often enough the auto reset circuit generates a reset RST to the microcontroller The circuit senses the voltage on a capacitor C46 being charged to 5V Either one of two comparators will generate RST if the voltage on C46 is too high or too low A third comparator sends AZRO to the microcontroller to indicate that the reset circuit requires service Service consists of AZRI being sent to the reset circuit which discharges capacitor C46 Initialization The board will carry out an initialization procedure every time the power is first turned on or any time the auto reset circuit generates a RST signal The initialization process is controlled by the program stored in the EPROM U19 and does not require the personal computer The board will not communicate with the personal computer until the entire initialization process has been successfully completed The major steps are listed in the order performed e Configure I O ports including RS 232 settings and 8255 configuration Sets X rays off lid latch open ECD coolers on baud rate etc e Initialize the filter wheel Locate the home flag via the optical sensor If it fails to find home set an error bit and continue e Initialize the sample tray if installed or the linear motion for R Theta or X Theta stage if installed Locate the home flag via the optical sensor Failure to locate the sample tray home stops the ini
124. d and is shown in the inset The ECD fan provides cooling air for the ECD heat sink The ECD electrically cooled detector assembly includes the Si Li detector crystal the Peltier coolers the preamplifier and the beryllium window It converts the X rays emitted and scattered by the sample into electrical pulses These pulses are amplified by the preamp before transmission to the pulse processor board The Si Li crystal and Peltier coolers are under high vacuum inside the housing The beryllium window acts as an X ray transparent vacuum tight seal The cooler power supply is a linear DC power supply with two outputs one for the ECD external coolers and the other for the ECD internal coolers This power supply is on whenever the instrument power cord is connected to an AC power source even when the instrument power switch is in the off position Spectrace Instruments QuanX Technical Manual 3 9 Product Description BACKUP BATTERY N Figure 3 5 Top view ECD model The backup battery is a 12V 7Ah sealed lead acid battery It provides power to the ECD ion pump power supply whenever the instrument power cord is not connected to an AC power source The battery can support the ECD
125. d is closed the lid interlock switch closes before the lid closed sensing switch does This creates a state where the lid is open but the interlock is closed X ray tube arcing The noise generated during an arc can disrupt the chamber board Faulty chamber control board Faulty primary lid interlock switch Troubleshooting Adjust the switches per procedure Run at low tube voltage to verify See High voltage arcing Verify by substitution replace if required Test with an ohmmeter replace if required ION PUMP CURRENT IS HIGH ECD Cause High gas load on the ion pump due to temporary outgassing usually after a detector warm up Poor vacuum in the detector housing or faulty ion pump Faulty ECD control board generated a false error message Faulty chamber control board performed an inaccurate voltage measurement Remedy Wait 4 hours to allow the ion pump to remove the gas It is normal for the current to be 2 3 times higher at room temperature than when the coolers are on Verify by determining the minimum detector temperature attainable If the detector operates normally moderately high ion pump current less than 100 uA is tolerable but will reduce the ion pump s life If a detector temperature sufficient to operate less than 190 K is not possible replace the ECD detector assembly Verify by measuring the ion pump current signal with a voltmeter at the ECD board J5 pins 5 to 6
126. data point I f not push F6 when in Main menu set print results after each sample to YES The count values should increase to a maximum then decrease for the Y portion of the scan and then do the same for the X portion The maximum count values should be at least 100 000 If not increase the acquisition time Note the X and Y positions with the maximum peak counts Calculate the correction factors using the following formulas X Position Correction Xmax 78 and the Y Position Correction Ymax 118 These corrections must be entered into the program from the Test Procedures menu under X POS CORR F3 and Y POS CORR F4 respectively After entering the corrections run the test again to verify that the maximum counts occur at x 78 2 and y 1184 1 If not rerun the test with a longer preset livetime after resetting the corrections to zero If the maximum counts with corrections still do not occur at x 78 2 and yz 1184 1 further diagnostic tests are needed starting with a check of the stage installation and a stability test Refer to the Technical Manual sections 7 and 10 for the stability test and other diagnostics Rename XYTABLE back to XYTABLE CP so that new XYTABLE files can be created without erasing XYTABLE CP Spectrace Instruments QuanX Technical Manual 11 5 Optional Equipment DISCARD THIS PAGE 12 Drawings and Schematic Diagrams Two types of drawings are included in this section Assembly Drawings and S
127. e 5 scfh 142 I h CH O Figure 11 1 Helium flush manifold vacuum helium panel inside view Spectrace Instruments QuanX Technical Manual Optional Equipment 11 3 11 2 3 Installation Disregard this section if the option was installed at the factory 1 Remove the detector assembly as detailed in Procedure 9 6 This is required to gain access to the chamber wall fitting Remove the brass hole plug from the chamber wall It is located next to the detector port opening Install the hose barb nipple in the chamber wall Use sealant on the threads Remove the vacuum helium panel from the rear panel of the instrument This is the middle panel with the vacuum nipple Allow the panel to hang from the large vacuum hose Remove hole plugs and dummy screws as required from the panel and install the helium manifold Remove the motherboard access panel from the rear panel Connect the helium manifold cable to the motherboard J6 connector This is the white 6 pin connector located behind the large black J7 connector see drawing 5911 0219 for the location Align the connector locking ramps for proper orientation Also check that it is not one pin off front to rear as the connector has no protection against this Connect the small hose from the helium manifold to the hose barb fitting on the sample chamber Reinstall the vacuum helium panel
128. e 11 2 for an illustration of the R Theta stage Technical drawings are included in Section 12 Drawings and Schematic Diagrams Spectrace Instruments QuanX Technical Manual Optional Equipment i 3 Suis d fa HOME SENSOR AND Je MERCENCY STOP e z el E E RE COVER e YE deu 3 Ale 9 ROTATION po IN I o f CALIBRATION TRAY ANA A Figure 11 2 R Theta stage top view Spectrace Instruments QuanX Technical Manual MOTO R 11 5 11 5 Optional Equipment 11 4 Y Theta Sample Stage 11 4 1 Description The Y Theta stage is used to hold silicon wafers Sizes accommodated are 4 5 6 and 8 inch wafers Sample positioning is fully automated and is under the control of the analysis program YTQUANX Positioning is accomplished by linear front to rear translation and up to 360 rotation See the QuanX Operators manual supplement for more information on the program operation The stage uses two stepping motors one for translation and one for rotation The translation axis uses the drive circuitry normally used for the sample tray rotation The rotation axis uses circuitry included only for optional equipment Each axis has an optical sensor and flag which are used to establish a home reference position The translation axis also includes emergency s
129. e alarm may be silenced by pressing the ALARM MUTE button located on the bias supply board in the card cage Spectrace Instruments QuanX Technical Manual Installation 5 7 5 5 Personal Computer Setup This section is applicable only if the computer was not supplied by Spectrace Instruments If the computer was supplied with the instrument skip this section and continue with Section 5 6 Performance Testing This section describes the procedures required to install the computer Both hardware assembly and software installation are required 5 5 1 QUANX Program Installation This section discusses the process of installing the analysis program QUANX onto the computer s fixed disk from the master release diskette For a new installation the INSTALL program is used If the program has previously been installed on the computer the UPDATE program is used For instruments equipped with special options such as the R Theta sample stage the program name may be different Conditions The computer must be completely assembled and operational The DOS operating system must be installed on the computer s fixed disk in drive C in a directory call DOS Required equipment Spectrace Instruments master release diskettes Safety precautions Routine Procedure Using INSTALL for a new installation The master diskette contains an installation program which will automatically create the required sub directories on the fixed disk and transfer al
130. e analysis software will operate properly This section does not attempt to detail the basic installation of DOS rather it addresses the particular configuration required to operate the QuanX system Refer to the DOS documentation for step by step installation instructions Conditions The computer must be completely assembled and operational DOS 5 0 or higher must be installed on the computer s hard disk drive C in a directory called DOS The computer s hardware configuration must meet the minimum requirements detailed in the specifications portion of Section 3 PRODUCT DESCRIPTION Required equipment None Safety precautions Routine Procedure There are two files located in the root directory which set the operating parameters of the computer CONFIG SYS and AUTOEXEC BAT DOS reads these files only during the computer s boot up sequence Spectrace Instruments QuanX Technical Manual Installation 5 9 When the analysis software QUANX is installed a CONFIG SYS and AUTOEXEC BAT file are automatically created It is recommended that the installation of the QUANX program be completed before continuing with this procedure Following is an example of each file with a brief description of the function of each line Note that the type of computer and amount of memory installed may affect the file entries Sample CONFIG SYS file DEVICE CADOSMHIMEM SYS DEVICE C DOS EMM386 EXE NOEMS X D800 DBFF DOS HIGH UMB DEVICE C
131. e and its output switches high A stable oscillator U9 begins to operate and flash the board front panel LN LEVEL LED The LLN signal generated from Q4 is connected to the 5911 0217 chamber control board where it may be read by the personal computer and also starts the LED flasher circuit which drives the DETECTOR TEMP light on the instrument front panel If the ALARM MUTE switch is pushed Q7 turns off and Q6 turns on Since Q7 is now held turned off by Q6 the audio alarm is turned off but the both LEDs continue to flash When the dewar is refilled the output of U8 switches low thus stopping the oscillator U9 ECD version All the circuit functions are the same The temperature sensor is located on the stack assembly inside the ECD housing so that the board is monitoring the Si Li detector crystal temperature The circuit resistor values are different from the LN version because the alarm trip point is higher for the ECD as it runs well above LN temperature Jumper settings Jumpers E1 E3 and E6 should be installed for the LN version of this board These settings will cause the FET protection circuit to respond only to high detector reset rate Jumpers E1 E3 and E5 should be installed for the ECD version of this board These settings will cause the FET protection circuit to respond to high detector temperature low LN as well as high detector reset rate Spectrace Instruments QuanX Technical Manual 4 19 Theory of Operation
132. e its input must be positive and no larger than 1 999 volts Conditioning utilizes a voltage divider network and or polarity inversion using op amps The X ray tube current is measured by a differential amplifier circuit formed by U10A and supporting components This circuit measures the voltage generated by the tube anode current flowing through a resistor on the X ray control board The output of the ADC ADCO 3 is read by U14 and transmitted to the PC over the RS 232 link where it is multiplied or divided as required to restore the correct decimal place position magnitude and polarity A thermistor TR1 is part of a voltage divider which generates a voltage that is a function of temperature This voltage is called AMBIENT and is measured by the ADC so that the internal enclosure temperature may be remotely monitored by the PC I O lines and device control The 8255s U14 and UI5 are configurable for use as input or output ports The configuration is set during board initialization and is as follows U14 port A output port B input port C output U15 port A output port B input port C output The 8255s are selected by chip select signals CS0 2 decoded by U13A from DATA CS and SELECT DATA CS is a shared signal line it is used for 8255 addressing and for X ray tube voltage and current data These functions are never carried out simultaneously so the line may be shared U16 is a dedicated input port The lid latch chamber vent
133. e motorized assemblies located inside the sample chamber area is detailed below 9 5 1 Filter Wheel Assembly l 1 1 See Figure 3 4 for the location of this assembly Turn off the instrument power Remove the sample tray and the metal plate which covers the sample chamber components or the special sample handling stage 1f installed The cover plate is secured with special vented screws save these for reuse Remove the two socket head screws which hold the assembly to the baseplate Disconnect the motor drive cable and sensor cable from the chamber distribution board J6 and J5 Guide the cables under the sample tray drive assembly if installed and remove the filter wheel assembly Install the replacement assembly by following steps in reverse order Make sure no cables are near the moving parts under the sample tray drive mounting plate Verify that the home position is established when the power is turned on The wheel should rotate change direction to locate the home flag center and stop 9 5 2 Sample Tray Drive Assembly 1 1 1 See Figure 3 4 for the location of this assembly Turn off the instrument power Remove the sample tray and the metal plate which covers the sample chamber components or the special sample handling stage if installed The cover plate is secured with special vented screws save these for reuse Remove the four vented socket head screws which hold the assembly to the baseplate Disconn
134. e or allow it to become dirty If required it may be cleaned with isopropyl alcohol 1 Remove the two screws holding the shield box in place Remove the power supply shield box assembly 1 Ifthe replacement power supply was supplied in a shield box install it by following the previous steps in reverse order 1 Ifthe replacement power supply is not in a shield box remove the four nuts and slide the old power supply from the shield box Install the new supply in the box be sure to replace the shoulder washers so that the power supply case is electrically isolated from the shield box Replace the assembly and connect the cables 1 Perform the following procedures a Run at several voltages and verify that the HV MONITOR value on the GEN STAT screen approximately matches the voltage selected b 7 12 Stability c System standardization is required before beginning quantitative analysis 9 4 2 PS1 5 amp 12V Switching 1 See Figure 7 3 for the location of this supply 1 Turn off the instrument power Disconnect the instrument power cord 1 Remove the four rear panel screws which hold the enclosure cover in place Remove the enclosure cover by grasping it on the bottom of each side and sliding it directly forward 1 Remove the X ray high voltage power supply as described in Procedure 9 4 1 1 Remove the screw that secures the front of the power supply tray to the enclosure 1 Disconnect the two white in line connectors J5 amp
135. eatures a bypass resistant actuator which requires a unique geometry actuator key to close the contacts X RAY ON WARNING LIGHT NTERLOCK SWITCH SAMPLE CHAMBER LID N CHAMBER LID D LATCH ASSEMBLY INTERLOCK SWITCH EE LEFT LID UN N DETECTOR TEMP LIGHT ADC INTERFACE CABLE E E ENE N RADIATION SI X RAY ICH VOLTAG POWER SUPPLY X RAY CONTROL BOARD Figure 3 2 Front view The X ray high voltage power supply produces the high voltage required for X ray tube operation It operates on 24V DC and generates up to 50kV and up to 2mA with a 50 watt power limitation The power supply is mounted in a shielded box to prevent noise pickup by the detector Spectrace Instruments QuanX Technical Manual Product Description 3 4 The radiation shield is a hinged steel plate used as a stop for stray radiation emitted from the X ray tube housing It is designed such that it must be in the normal or down position before the enclosure cover will fit on the instrument The shield may be flipped up for service access WARNING To prevent exposure to radiation the radiation shield must be in the normal down position whenever X rays are being generated The power supply tray holds all the DC power
136. ect the motor drive cable and sensor cable from the chamber distribution board J3 and J4 Lift the assembly out Install the replacement assembly by following steps in reverse order Make sure no cables are near the moving parts under the mounting plate Verify that the home position is established when the power is turned on The tray drive wheel should rotate change direction to locate the home flag center and stop 9 5 3 Sample Spinner Drive Assembly 1 1 1 See Figure 3 4 for the location of this assembly Turn off the instrument power Remove the sample tray and the metal plate which covers the sample chamber components or the special sample handling stage if installed The cover plate is secured with special vented screws save these for reuse Remove the four vented screws which hold the assembly to the baseplate Spectrace Instruments QuanX Technical Manual 9 13 Component Replacement 1 Disconnect the motor cable from the chamber distribution board J7 Remove the cable clamp screw securing the motor cable to the baseplate near the detector snout 1 Guide the cable under the sample tray drive assembly Lift the spinner drive assembly out 1 Install the replacement assembly by following steps in reverse order Make sure no cables are near the moving parts under the sample tray drive assembly mounting plate 1 Verify that the motor turns for approximately 1 2 second immediately after the power is turned on
137. ection The PC sends commands X rays on vacuum pump on etc to and receives status from the chamber control board located in the QuanX card cage 3 2 2 Component Identification and Description Figure 3 2 shows a front view of the QuanX without a detector installed and with the enclosure cover removed Each item identified with a callout is discussed below The left lid on the top of the instrument can be opened to provide access to the detector and detector electronics The configuration of components is different for the LN and the ECD models In the LN model the dewar is under the access cover The dewar can be filled by removing the cap and adding LN until the level reaches the neck of the dewar The LN cooled detector should be refilled each week regardless of whether the unit will be used or not In the ECD model the front area under the cover holds the ECD support electronics Indicators and controls for the ECD Peltier coolers are located in this area The two interlock switches prevent the generation of X rays and high voltage when the left lid is open or when the enclosure cover is removed Both switches are of the pull to cheat design the switch may be bypassed by pulling out on its actuator lever Closing or installing the cover resets the actuator thereby restoring normal switch operation This feature is useful for service purposes The lid latch assembly contains a solenoid and two switches The solenoid is energized to
138. ector outputs Once the ion pump current has dropped the coolers are turned off again This cycling continues until the pump current stays below 300HA The QuanX ECD has extremely low leakage and gas buildup is rarely a problem Therefore software control of the coolers is not provided in the QUANX analysis program It is possible to initiate a warm up by software by using the diagnostic program ECHOA described in Section 8 of this manual Note that turning off the coolers by switch SW1 does not initiate the auto defrost cycle Temperature regulation The ECD has two sets of thermoelectric coolers They are referred to as the internal coolers inside the vacuum and the external coolers outside the vacuum The internal coolers operate at a fixed power level at all times The external cooler power is varied to maintain temperature regulation of the Si Li detector crystal The actual point of regulation is referred to as the base Spectrace Instruments QuanX Technical Manual 4 21 Theory of Operation The internal cooler power enters on J3 pin 8 and passes through relay K1 then out to the ECD on J4 pin 3 K1 is controlled by SW1 which is the primary means of turning the ECD coolers on and off The internal cooler voltage also goes out J1 pin 14 to be measured by the chamber control board ADC circuit The internal cooler power adjustment is made at the cooler power supply PS5 The external cooler voltage is varied by utilizing the sense input p
139. ede 7 44 7 21 Chamber Vacuum Fest im ee ei de iet entere Eb ete Ce OH aes 7 46 7 22 System Status V Oltages eee tee dere e Ede eed iege tee eden 7 47 7 23 Hehum Flush Operation ero ais 7 48 Spectrace Instruments QuanX Technical Manual 7 24 Detector Temperature Measurement BC 7 25 Beryllium Window Cleaning Procedure eese nennen Spectrace Instruments QuanX Technical Manual 7 1 Test and Adjustment Procedures 7 1 Introduction This section contains procedures for adjusting the operating characteristics of individual hardware modules and procedures which test the system or its modules on a pass fail basis They are used for checkout of the instrument after installation or replacement of a component and for troubleshooting Other sections of the manual reference the tests in this section The procedures assume that the reader need not be instructed on the use of a voltmeter or an oscilloscope to make a voltage measurement or signal waveform measurement or to get a program on diskette loaded and running on a personal computer Many of the test procedures are performed while running the QUANX program Directions to run this program and to make use of the soft keys available under its various menus are found in the Spectrace QuanX Operators manual In this section the QUANX soft keys are always identified by name of the function they invoke under a given menu rather than by the numbers F1 F10 by which they are labeled on
140. ee the QuanX Operators manual supplement for more information on the program operation The stage uses two stepping motors for translation The X translation axis uses the drive circuitry normally used for sample tray rotation The Y translation axis uses circuitry included only for optional equipment Each axis has an optical sensor and flag which are used to establish a home reference position Both axes also includes emergency stop switches which interrupt the motor power if the stage travels beyond its normal operating range A special chamber board ROM chip P N 8140 0131 is required to operate the XY stage Also the chamber board switches SW1 and SW2 must be set to the THETA position See Figure 11 4 for an illustration of the XY stage Technical drawings are included in Section 12 Drawings and Schematic Diagrams N e Ce L 7 e CNN Pela l 4 HB E Oto Le E za 8 B Lil pag ana ee Vo al Y le g e EIN E b 6 E E Y Ej E T El Spectrace i A Figure 11 4 XY stage top view Spectrace Instruments QuanX Technical Manual 11 5 Optional Equipment 11 5 2 Installation Disregard this
141. es can cause severe burns on contact with skin eyes or lungs Do not allow skin contact with the liquid and do not breathe the vapors boiling off the liquid Nature of the hazard Liquid nitrogen exists at extremely low temperatures 320 F 196 C 77K Skin contact with liquid cryogens or with boiled off gases that are still at cryogenic temperatures can cause burns as severe as high temperature burns Breathing the vapor boiling out of the dewar can cause injury to air passages and lungs that is just as severe as burns from breathing hot gases Delicate tissues especially the eyes can be damaged even by a brief exposure Preventive measures Always handle dewars very carefully Always wear protective gear gloves clothing goggles when handling cryogens Never breathe the gases boiling out of a dewar Stay clear of boiling and splashing LN LN will always boil when it is transferred to a warm container or when something is inserted into it Transfer LN slowly Never touch uninsulated plumbing or containers that hold LN Skin may adhere to these cold surfaces and tear when pulled away Never put hands in the LN Use only vessels designed for use with LN e g LN dewars for filling transferring and using LN When filling dewars use a metal funnel or one that is rated for low temperature Emergency measures Treat LN burns as you would a case of frostbite Contact a physician for medical attention Spectrace Instruments QuanX
142. f the sample is not a standard 1 25 diameter size 1 Select STRAY LINES III test from the procedure menu or set up an acquisition with the following conditions Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 40 Overall setup ACQUISITION PARAMETERS ANALYSIS TECHNIQUE Tube voltage SOkV Method i Peak ratios Tube current 0 20 mA 0 40 ECD Mode Run unknowns Filter used Cu thick Std file 700 Livetime 500 sec Preset count Ok Max energy 40 keV Atmosphere Air Warmup 0sec SPECTRUM PROCESSING SAVE ON DISK Ref file no 700 Spectrum Elements of int Ag Sn R1 R2 Intensities File number Results Ext program Spectrum processing setup SPECTRUM PROCESSING 1 AG NET ROI 21580 22580 EV 2 SN NET ROI 24600 25700 EV 3 R1 GROSS ROI lt 0 40920 EV gt 4 R2 GROSS ROI lt 15000 16000 EV gt Count rate range setup AMP COUNT RATE HIGH Peak ratio setup SETUP RATIO ELEMENT S ANALYZED 1 AG 2 SN 3 R2 RATIO TO R1 Return to the procedure menu and RUN the STRAY LINES III test enter 1 for the number of unknowns The system automatically runs the spectrum processing and analysis technique at the completion of the acquisition The dead time should be 40 to 50 If not press ACQU MENU amp ACQU PAR and adjust the tube current The result is the ratio of each element s intensity to the total spectrum Spectrace Instruments Quan
143. failure listed for X rays off is the See the causes and remedies for high dead cause but is only significant with the time with X rays off X rays on Spectrace Instruments QuanX Technical Manual 10 18 DEAD TIME IS LOW OR ERRATIC Cause The X ray tube voltage or current is set too low Improper filter selected Fast discriminator requires adjustment Improper pulse processor count rate range selected Detector high voltage bias is off ADC interface cable is loose A board is not inserted correctly in the card cage X ray control board requires adjustment or is faulty Filter positioning mechanism is faulty Faulty ADC board Faulty pulse processor board Faulty power supply Troubleshooting Remedy Raise the kV and or mA settings and restart the acquisition Select a thinner filter Adjust to 150 25 with X rays off Select a lower range Verify that the HV light on the bias supply is off then see Detector high voltage bias is off Turn off the power Reseat the ADC interface cable connections at each end Turn off the power Reseat all the boards firmly Verify with X ray control voltage and anode current entries in the GEN STAT screen Replace if required Verify by exiting and restarting QUANX An error message will appear if the mechanism doesn t initialize properly See Filters do not position correctly Verify by substitution replace if required Verify by
144. feedback network consisting of CR5 CR6 R21 R23 R33 and Q1 A variable resistor R20 is used to calibrate the gain of the oscillator to a nominal value FET Q1 functions as a voltage variable resistor and allows the oscillator amplitude to be varied by a control voltage from the stabilizing feedback network Transistors Q8 and Q9 provide the power gain necessary to drive a voltage multiplier circuit consisting of T1 C2 C8 CR1 CR4 and R16 R18 This circuit converts the oscillator output to 1000 VDC The desired detector bias voltage is selected by connecting resistor R3 to the appropriate tap on the voltage divider formed by resistors R5 R15 Thus the detector bias voltage is jumper selectable The default values of this jumper setting are 300V for the ECD and 600V for LN cooled detectors U3 and its associated components form a voltage stabilizing feedback network which compares the multiplier output voltage with a reference voltage Any deviation from 1000 VDC produces an error voltage which changes the oscillator amplitude to correct the deviation A variable resistor R26 is adjusted to set the output of the error amplifier U3 to its nominal value when the multiplier output is 1000 VDC Thus the bias voltage is very stable and has very low ripple FET Protection circuit The protection circuit is designed to guard the input FET against damage caused by system warm up due to loss of liquid nitrogen vacuum failure or by improper system
145. g lead before personal contact is established 2 1 3 Survey Meters and Dosimeter Badges Regular radiation survey of the instrument may be desired or in some cases required by your state A survey meter designed to be used with X radiation in the energy range of at least 30 to 50keV is required One such model is the Victoreen 493 with a 489 35 GM probe The response of this type of meter is kV dependent therefore the true reading is obtained by applying a correction factor to the apparent reading as explained in the meter manual It is available from Victoreen Inc 6000 Cochran Road Clevland Ohio 44139 3395 216 248 9300 Spectrace Instruments QuanX Technical Manual 2 3 Safety Spectrace Instruments recommends the use of personal dosimeter badges for all personal operating radiation producing devices This may be required by your state as well Normally a contract is established with a qualified vendor for monthly exchange and examination of badges One such company is Radiation Detection Company 162 Wolfe Road Sunnyvale CA 94088 408 735 8700 2 1 4 State Mandated Safety Requirements Most states in the USA require registration of any radiation producing device and several states require regular safety testing and on site inspections Contact your state department of health to determine your local requirements A typical requirement may include at least the following procedures e Semiannual safety interlock functional te
146. g light flashed on then off when the X rays were turned on The light stays off and the computer says it is off and the ENABLE LIGHT LED on the chamber board is off Note QUANX program version 1 35c has a bug which will cause a similar symptom If the confirm signal is bad the light will flash an error message will flash on the screen and the program will return to the menu In this case see the confirm signal symptom below Remed Plug in the rear panel connector Verify by checking the chamber board lights If the ENABLE LIGHT LED is on but the warning light is off replace the display board Otherwise see next cause Verify by checking its lights When the X rays attempt to turn on the ENABLE LIGHT LED should light if not replace the chamber board Explanation High current surge on the 24V supply when the X rays tried to turn on The 24V drops low and the chamber board registers this as an open interlock and turns off the warning light The 24V recovers so the PC doesn t detect an interlock failure but does detect the fact that the light is off The ENABLE light turned off from the voltage drop not by computer command The computer doesn t send an X ray off command until the error message is cleared from the screen by the operator Spectrace Instruments QuanX Technical Manual 10 33 Reference 5919 0217 confirm Procedure 9 3 1 Reference Reference Procedure 9 3 5 5919 0217 enable lamp
147. gic circuits which monitor the voltage level of INTERIN the status of the X RAYS ON light and the status of the lid closed and lid locked switches located on the chamber lid latch assembly 8100 7407 The Spectrace Instruments QuanX Technical Manual Theory of Operation 4 6 logic circuit will not energize relay K1 unless the computer issues an X ray on command and the INTERIN signal is at 24 volts switches are all closed and the X RAYS ON light is actually illuminated and the chamber lid is closed and locked Relay K3 forms part of the second redundant chamber lid interlock circuit It is controlled only by the lid closed and lid locked switches located on the lid latch assembly Note that these switches operate on an independent 5V logic signal they are not part of the 24V primary interlock loop Anytime the chamber lid is closed and locked K3 is energized In this condition K1 serves to turn the X rays on and off in response to computer command K1 and K3 are wired in series so that if either one is open the X rays will not be generated Once the 24 volt signal passes through relays K1 and K3 it is named INTEROUT and leaves the chamber control board on J1 pin 54 This voltage is connected again to the X ray control board on J3 pin 1 where it is routed directly to J4 pin 1 From J4 pin 1 cable 5101 0378 carries the 24V to the X ray high voltage power supply and X rays are generated Note that the 24V supply
148. gnals from the 8255 and raise the FET drive voltage to 12V The sample spinner and Theta stage options are never installed simultaneously and so are able to share a single set of driver transistors Q10 11 19 21 Switches SW1 and SW2 select which control signals are routed to the transistors The sample spinner motor doesn t require position control so U4 is used to generate the motor signals the microcontroller can only start and stop it via the OE pin The home sensors are read from the FHD filter home detect SHD sample tray and THD theta inputs These signals are logic high when the home flag is inside the optical sensor and low otherwise LEDs D9 11 give a visual indication of the home status for troubleshooting purposes on home Vacuum sense and control The status of the vacuum is determined using a thermocouple vacuum sensor mounted in the chamber It contains two crossed wires One of the wires is heated with an AC current resulting in a DC voltage between the two wires due to the dissimilar metals junction As the vacuum increases there are less gas molecules to conduct heat away from the junction and its temperature and hence the DC voltage increases The AC current is supplied to the vacuum sensor by transformer T1 U2 generates a square wave which drives T1 via Q14 Voltage regulator U34 is used to adjust the voltage supplied to T1 which regulates the AC current to the sensor The op amp U33A amplifies the signal from
149. gy Calibration The calibration should be performed on the count rate range used for unknowns analysis because there may be a small energy calibration deviation between the three count rate ranges Test equipment Spectrace OFHC copper calibration standard Procedure Note Steps 2 6 are to verify or set the correct acquisition parameters This setup will be saved and remain as the default configuration until it is changed again Therefore those steps are normally required only once and need not be executed daily 1 Start the QUANX program The PROCEDURE menu will be displayed 1 Press SETUP SYS STAT and ECAL CONFG Verify the acquisition parameters Tube voltage 20 kV Tube current 0 08 mA 0 16 ECD Filter Pd medium Livetime 600 sec Preset count OK Max energy 20 keV Atmosphere Air Warmup 20 sec 1 Press SYS STAT and COUNT RATE and set the desired range Medium for most applications Press EXIT twice Enter 8041 for copper Ka when prompted for the energy of the line Press EXIT two times to return to the PROCEDURE menu Press ENRGY CALIB to run the calibration procedure The dead time should be approximately 50 If not press ACQU MENU amp ACQU PARM and adjust the tube current Rh a p 1 The procedure displays the current value of the gain DAC and the difference error between the actual calibration and the ideal If the error is greater than 20 terminate this procedure and run the Initial Energy Calibration
150. he safety features of the QuanX include the following The X ray source the sample and the detector are installed in an enclosure which provides adequate radiation shielding The sample chamber access doors and X ray generation and detection components are protected by an interlock circuit A program called XRAYOFF is located in the AUTOEXEC BAT file so it is executed automatically every time the PC is booted to make sure that the X rays are turned off This is useful in the event the computer failed due to a power failure or some other cause when the X rays were still on Note that there is no inherent harm in leaving the X rays on as long as the interlocks are in proper working order Thus the user or technician can turn the X rays off by rebooting the computer power off on or press CNTL ALT DELETE Spectrace Instruments QuanX Technical Manual Safety 2 6 2 3 Electrical Shock Hazard High Voltage WARNING Voltages and currents used in electrical equipment are capable of causing severe injury or death from electrocution Avoid accidental contact with live circuit components Nature of the hazard In electrical equipment the shock hazard is associated primarily with components of the AC distribution system such as circuit components connectors wiring termination points and other exposed hot spots In the QuanX potentially lethal voltages and currents exist at the following locations e Inside the AC distribution box
151. hnical Manual 7 39 Test and Adjustment Procedures Spectrum processing setup SPECTRUM PROCESSING 1 CU NET ROI lt 7740 8320 EV gt 2 FE NET ROI lt 6120 6660 EV gt 3 W NET ROI 8100 8680 EV 4 R1 GROSS ROI 0 30000 EV 5 R2 GROSS ROI 5000 5500 EV Count rate range setup AMP COUNT RATE MEDIUM Peak ratio setup SETUP RATIO ELEMENT S ANALYZED 1 CU 2 FE 3 W 4 R2 RATIO TO R1 3 Return to the procedure menu and RUN the STRAY LINES II test enter 1 for the number of unknowns The system automatically runs the spectrum processing and analysis technique at the completion of the acquisition 3 The dead time should be 4046 to 5096 If not press ACQU MENU amp ACQU PAR and adjust the tube current 3 The result is the ratio of each element s intensity to the total spectrum 3 Verify that the ratio percent for each element is 0 015 or less R2 is a measure of the background level verify that the ratio percent is 0 12 or less for ECD systems This parameter is not specified for LN systems NOTE If the result exceeds this value clean the surface of the test sample with a solvent and repeat the test Any contamination of the surface may cause high results Also check that the detector collimator is installed and properly aligned 7 18 2 Stray Lines III 50kV Procedure 1 Place the plastic scatter block in the chamber Use the single sample tray horseshoe removed i
152. hout the crystal volume When an X ray photon enters the active region of the detector electron hole pairs are created by the process of photo ionization These mobile charges are collected at the contacts by the action of the electric field which pushes the electrons to the signal contact and the holes to the Schottky barrier contact This collected charge is the sensor s output signal and is connected to the gate of the FET for amplification Since an electron hole pair is produced for each 3 8 eV of photon energy the signal amplitude is proportional the photon energy The liquid nitrogen dewar shown in Figure 4 5 is an extremely well insulated double walled vessel The space between the vessels is lined with super insulation and is evacuated to a high vacuum in order to eliminate heat loss due to gas conduction A cold finger extends from the inner vessel to the stack assembly which holds the Si Li detector crystal and FET The cold finger and stack assembly are under the same high vacuum to prevent heat conduction and to prevent contamination of the detector crystal The detector crystal operates at liquid nitrogen temperature 196 C however the FET temperature is raised slightly with a heater resistor to reduce electrical noise The vacuum inside the dewar is maintained by activated carbon a type of molecular sieve or getter Due to its processing the carbon presents a very large surface area and is highly adsorptive when cooled to low tempe
153. ies Section 11 Optional Equipment This section gives an overview of some of the standard options available on the QuanX Section 12 Drawings and Schematic Diagrams This section contains electrical and mechanical drawings Spectrace Instruments QuanX Technical Manual 1 3 General Information 1 3 Reference Documents Spectrace Manuals and Publications QuanX Operator s manual part number 0120 0040 Energy Dispersive X ray Fluorescence Spectrometry An Introduction Spectrace Instruments 1994 Spectrace Instruments QuanX Technical Manual General Information 1 4 1 4 Service and Support Telephone Support A service technician is available for help or information normally the technician responsible for your geographic region To obtain the technician s direct number or if the technician is not available call Spectrace Instruments Customer Service 408 744 1414 Remote Diagnostic Troubleshooting Spectrace is equipped to troubleshoot the QuanX via a modem hookup with the instrument Extensive troubleshooting is provided if both parties feel the problem may be resolved over the telephone On Site Service On site service is available after initial contact and troubleshooting via the phone Service Contracts Spectrace offers a service contract that will provide the customer a means of maintaining the instrument with the highest on line time possible Various designs are available to suit the customers needs Contact a c
154. ies the DETECTOR STATUS screen typical minimum and maximum values for a properly functioning system The table is as presented on the computer screen The values given are the average values observed over several seconds The GENERAL STATUS and ECD STATUS screens have the nominal range listed on screen The table is only valid when the X rays are off the detector coolers have been on at least two hours and the power has been on at least 15 minutes DETECTOR STATUS PHA STATUS BIAS VOLTAGE AMP COUNT RATE ERI DEAD TIME 20 PREAMP RESETS SEC LN SYSTEMS per 10 sec 1 per 3 sec ECD SYSTEMS o 10 ZERO OFFSET eV o 0 4 0 4 ZERO WIDTH eV LN SYSTEMS LOW RANGE MED RANGE HIGH RANGE ECD SYSTEMS LOW RANGE MED RANGE HIGH RANGE ZERO DAC GAIN DAC DETECTOR TEMPERATURE K ECD SYSTEMS ONLY Spectrace Instruments QuanX Technical Manual Troubleshooting 10 3 10 3 Hardware Error Messages Introduction Most of the system error messages which are not software related are listed here in alphabetical order This section is primarily intended for use by the system operator although the service technician will also find it useful Each message is followed by an explanation of its meaning a warning or caution if appropriate and a cause and remedy chart The cause and remedy charts have the following features e The charts are arranged with the most common causes listed first e The remedies are targeted
155. if required 1 Install the detector assembly Verify that its flange depresses the interlock switch lever located on the chamber port 1 Due to variations from part to part the location of the dewar varies slightly The design intent is that the flange to baseplate screws determine the location then a leveling set screw is used to support the dewar weight and relieve stress on the neck Turn the set screw on the dewar frame counter clockwise to raise it Install the four screws which hold the flange to the chamber baseplate The screws must have nylon shoulder insulators around them Tighten the screws evenly 1 Turn the set screw on the dewar frame just until it contacts the floor and starts to lift the dewar Install and tighten the screw that fastens the dewar frame to the chassis 1 Before connecting the preamp cable use an ohmmeter to measure the resistance between the detector body non painted area and chassis ground There must be no electrical contact open or infinite reading If there is electrical contact make sure the preamp cable housing isn t touching ground and check that the dewar does not touch the X ray control board mounting bracket The cause of the short must be found and corrected before continuing 1 Connect the preamp cable to the bias supply board 1 Fill the dewar with LN if necessary if it was dry wait two hours before testing Reassemble the remaining components 1 Perform the following procedure
156. if required Measure and adjust per procedure Replace if required Verify by running the RESOLUTION STABILITY test If peak centroid deviation is good and resolution deviation is gt 5 eV or is high see Resolution is poor ENERGY CALIBRATION IS UNSTABLE LONG TERM PEAK SHIFT SYSTEM FAILED TO CALIBRATE HARDWARE PROBLEM Cause Fast discriminator requires adjustment Hardware calibration is too far out of adjustment Remedy Adjust the fast discriminator control for 150 25 counts sec with the X rays off Adjust the pulse processor calibration per procedure Spectrace Instruments QuanX Technical Manual 10 21 Procedure 7 24 Procedure 9 6 2 Int TB 8 amp 3 Ext TB 7 amp 4 Reference Procedure 7 2 Procedure 7 9 Procedure 7 12 Procedure 9 3 2 Procedure 9 3 4 Procedure 7 4 1 Procedure 7 12 Reference Procedure 72 Procedure 7 9 10 22 Long term peak shift large gain DAC variations between successful calibrations caused by one of the following Faulty pulse processor module Faulty ADC board Faulty power supply Faulty detector preamplifier board Troubleshooting Verify by substitution replace if required Verify by substitution replace if required Measure and adjust per procedure Replace if required Verify by substitution replace if required EXTERNAL COOLER VOLTAGE IS HIGH EXTERNAL COOLER VOLTAGE IS HIGH Cause Ambient te
157. ink temperature Read ECD external cooler voltage Read ECD battery voltage Read ECD ion pump current Read 12V PS1 sw Read X ray high voltage monitor Read X ray high voltage control Read X ray H V power supply source HV 24 Read 12V PS3 lin Read 424V PS4 lin Usage Diagnostic Software Respons e AUF AUL AUH AUB AUX AXXXX AXXXX AXXXX AXXXX AXXXX AXXXX AXXXX AXXXX AXXXX AXXXX AXXXX AXXXX AXXXX 8 8 Response Description Helium flush is OFF Low flow valve is ON High flow valve is ON Both low and high flow valves are ON Helium option not installed or incoming pressure is low Temp C 69 481358 0 177285xxxx 0 0001 18 xxxx 2 V xxxx 100 V xxxx 100 Temp C 69 481358 0 177285xxxx 0 0001 18 xxxx 2 V xxxx 100 V xxxx 100 MA xxxx 10 V xxxx 100 kV 0 05 xxxx Control voltage 2 xxxx 100 kV 5 control voltage V xxxx 10 V xxxx 100 V xxxx 10 Spectrace Instruments QuanX Technical Manual 8 9 Comman d query QVI3 QV14 QVIS QV16 QV17 QVI18 QV19 QV20 QV21 QV22 QV23 QW QY if supported QZ Name Read detector bias 1V test point Read 12V PS3 lin Read 24V PS4 lin Read 5V PS1 sw Read 12V PS1 sw Read 424V PS2B sw Read INTEROUT interlock signal Read ECD stack temperature Read ECD stack temperature Read X ray t
158. interrupt has been cleared Whenever the ADC sends data to the computer in response to a command it writes two bytes into another pair of registers This sets a bit in a register the computer uses for polling When the computer sees that this bit is set it reads the information sent to it This action clears the bit that was set The ADC also sends status information to the computer This is a byte written to its own register and sets its own polling bit Spectrace Instruments QuanX Technical Manual Theory of Operation 4 20 4 12 ECD Control Board The part number of this board is 5911 0207 and the circuit is shown in schematic 5919 0207 references to the model 8000 apply to the QuanX This board is responsible for regulating the ECD temperature protecting the ECD from damage generating alarm signals and supporting the ECD ion pump Power supplies The board runs on a single 24 VDC power source supplied via J3 pin 6 Three voltage regulators U6 8 are used to generate local supply voltages U8 is adjusted to 12V output by R41 This supply is used to operate the integrated circuits on the board U7 is set for approximately 14 3V output by R40 and is used to charge the ion pump backup battery The battery charging voltage is 13 6V after the D3 diode drop U6 is fixed at 12V output and is used to operate the ion pump when the instrument power cord is plugged into an AC power source Connector J2 is not used in the QuanX Ion pump
159. ion 1 1 Select the PILEUP TEST from the procedure menu or set up an acquisition with the following conditions Overall setup ACQUISITION PARAMETERS ANALYSIS TECHNIQUE Tube voltage 20kV Method Peak ratios Tube current 0 18 mA 0 36 ECD Mode Run unknowns Filter used Pd medium Std file 500 Livetime 500 sec Preset count Ok Max energy 20keV Atmosphere Air Warmup 10sec SPECTRUM PROCESSING SAVE ON DISK Ref file no 500 Spectrum Elements of int Mn RI Intensities File number Results Ext program Spectrum processing setup SPECTRUM PROCESSING 1 MN NET ROI 5320 6220 EV 2 R1 NET ROI 11460 12120 EV Count rate range setup AMP COUNT RATE MEDIUM Spectrace Instruments QuanX Technical Manual 7 37 Test and Adjustment Procedures Peak ratio setup SETUP RATIO ELEMENT S ANALYZED 1 R1 2 RATIO TO MN 3 Return to the procedure menu and RUN the PILEUP TEST enter 1 for the number of unknowns The system automatically runs the spectrum processing and analysis technique at the completion of the acquisition 3 The dead time should be approximately 5096 If not press ACQU MENU amp ACQU PAR and adjust the tube current 3 The system will automatically calculate the ratio of the sum peak region R1 to the parent peak region MN 3 Verify that the ratio percent is 0 30 or less Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 38
160. ion of the absolute error the number of counts in the peak and the peak position stability Cause PRESET COUNT set to non zero value Count rate is too low Remed Enter ECAL CONFG and set the PRESET COUNT 0 Raise mA to achieve approximately 50 dead time Spectrace Instruments QuanX Technical Manual Troubleshooting 10 9 Hardware calibration is too far out of adjustment for the system to compensate Fast discriminator requires adjustment Hardware problem Adjust the hardware calibration per Procedure 7 9 Initial Energy Calibration Adjust to 150 25 with X rays off see Procedure 7 2 See the troubleshooting chart in the next section X RAYS NOT OFF HARDWARE PROBLEM Confirm signal failure The computer attempted to turn off the X rays but the chamber control board is reporting that the X rays are still on Cause Hardware failure Technical reference Remed See the troubleshooting chart in the next section See schematic 5919 0217 chamber control board signal CONFIRM X RAYS NOT ON HARDWARE PROBLEM Confirm signal failure The X rays should be on but the chamber control board is reporting that the X rays are off Cause Hardware failure Technical reference Remed See the troubleshooting chart in the next section See schematic 5919 0217 chamber control board signal CONFIRM X RAYS NOT ON HARDWARE PROBLEM Interlock has opened The X rays should be on
161. is low Faulty pulse processor module Faulty ADC board Remedy Adjust the zero control on the pulse processor module until the zero DAC is below 200 Measure per procedure or measure the voltage across the small capacitor above the ADC interface cable connector on the ADC Must be greater than 4 95 V Verify by substitution replace if required Verify by substitution replace if required ADC BOARD DOES NOT COMMUNICATE FAILED TO DOWNLOAD FILE TO ADC Reference 5919 0207 LEE R23 5919 0207 ion pump on Reference Procedure 7 9 Procedure 7 4 1 Procedure 9 3 2 Procedure 9 3 4 Reference Procedure 7 9 Procedure 7 4 1 Procedure 9 3 2 Procedure 9 3 4 ADC FAILED TO RESPOND RETRY PREVIOUS TASK OR CHECK HARDWARE AND RELOAD PROGRAM Cause ADC requires a logic reset ADC interface cable is disconnected or loose Remedy Exit the program cycle the power off and on restart the program Turn off the power Reseat the ADC interface cable connections at each end Spectrace Instruments QuanX Technical Manual Reference Figure 3 6 Troubleshooting ADC board is not inserted correctly in the card cage Faulty ADC board Turn off the power Reseat the ADC firmly Verify by substitution replace if required Faulty power supply Measure and adjust per procedure Replace if required Switch S2 I O port address on the ADC interface board
162. is not set correctly Set the switch as specified in the installation procedure Faulty ADC interface board Verify by substitution replace if required AMBIENT TEMPERATURE INSIDE THE INSTRUMENT IS HIGH HIGH AMBIENT TEMP CHECK SYSTEM STATUS Cause Remedy Outside ambient Reduce th xternal ambient temperature is above 32 temperature Es Fan inlet on rear panel is blocked Verify that there is at least 4 inches of free space behind the inlet Loose or disconnected hose Check the enclosure cooling fan flexible hose connections Cooling system clogged with dirt Visually inspect the holes under the card cage motherboard Faulty cooling fan Blow a heat gun on the sensor located on the front of the card cage The fan speed should increase Check for air flow out of the holes in the floor Replace fan if required Faulty chamber control board generated a false error signal Verify and replace the appropriate board BACKGROUND LEVEL IS HIGH Cause Remedy Analysis conditions and or method are not optimized for the elements of interest Contact a factory applications specialist Fast discriminator requires adjustment Adjust the fast discriminator control for 150 25 counts sec with the X rays off Verify on the GENERAL STATUS screen The bias supply 1v should be greater than 0 95 If it is low replace the bias supply module Low detector bias supply voltage Faulty pulse processor module
163. l the required files A new copy of the files AUTOEXEC BAT and CONFIG SYS will be installed in the root directory of drive C Previously existing versions of these files if any will be renamed with the extension BAK to AUTOEXEC BAK and CONFIG BAK and stored in the root directory Because these files may contain entries unique to the particular configuration of your computer such as hardware device drivers it may be necessary to edit the new version and add any required instructions A word processing program or the DOS EDIT function may be used to view and modify the files The new AUTOEXEC BAT and CONFIG SYS files contain the default parameters for a typical installation The CONFIG SYS file contains a statement which reserves a block of memory for the ADC interface board If an address other than the default is chosen for this board the CONFIG SYS file must be modified See the sections DOS Operating System Configuration and ADC Interface Board Installation in this chapter for more information Note Pressing ENTER return is implied for each of the following commands Also the notation C gt is used to indicate the DOS prompt and is not to be typed when entering DOS commands 1 Insert the master diskette into drive A and type C gt a install follow the on screen instructions as required Spectrace Instruments QuanX Technical Manual 5 8 Installation 2 Use DOS EDIT to copy any required statements from the CONFIG BAK and A
164. late holding the detector adapter assembly with two mounting screws 1 Remove the set screws and verify that the adapter flange depresses the interlock switch lever located on the chamber port 1 Install the two remaining mounting screws which hold the detector to the chamber baseplate Tighten all four screws evenly 1 Follow the Technical Manual instructions section 9 6 1 or 9 6 2 to complete the detector installation 1 Replace the old detector collimator with the new one provided 11 5 2 2 Attaching the Stage 1 Ifadetector adapter ring has just been installed go to step 5 1 Turn off the instrument power switch For ECD systems disconnect the instrument power cord This is required to remove all power from the chamber board socket 1 Remove the baseplate cover and tray support pads if present from the baseplate 1 Remove the tray drive assembly if present 1 Replace the old filter wheel collimator with the new one provided Spectrace Instruments QuanX Technical Manual Optional Equipment 11 5 2 You should now see the distribution board with connectors for the X Y stage cables Note the markings on the connectors on both the cables and the distribution board Rest the left side of the stage on the left side of the baseplate holding up the right side of the stage to allow access to the distribution board connectors Connect all four connectors to the chamber distribution board by matching the numbers m
165. le spinner tray then load 10 brass samples in the spinner cups This test must be performed with the samples rotating If the system has both types of tray or spare trays repeat the test for the additional tray s 1 Select the TRAY ACCURACY test from the procedure menu and press SETUP or set up the following conditions Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 32 Overall setup ACQUISITION PARAMETERS ANALYSIS TECHNIQUE Tube voltage 20kV Method Linear Tube current 0 06 mA 0 12 ECD Mode Run unknowns Filter used Pd medium Std file 300 Livetime 100 sec Preset count Ok Max energy 20keV Atmosphere Air Warmup 600 sec SPECTRUM PROCESSING SAVE ON DISK Ref file no 300 Spectrum Elements of int Brass Intensities File number Results Ext program Spectrum processing setup SPECTRUM PROCESSING 1 BRASS GROSS ROI lt 7200 10080 EV gt Standards file setup STANDARDS FILE ELEMENTS OF INTEREST File no 200 Inten Position 1 IN Position 2 IN Entries 1 to 20 are identical Enter only 1 to 10 for the spinner tray Position 20 IN Zero ref IN Count rate range setup AMP COUNT RATE MEDIUM 5 Highlight ACQUISITION PARAMETERS and press RUN Answer the prompts as follows No unknowns 20 10 for the spinner tray All others Press ENTER 4 Highlight SPECTRUM PROCESSING and press RUN Enter 20 10 for the spinner tray for the number of samp
166. le with X rays is the X ray tube shown schematically in Figure 4 1 The tungsten filament is heated by a pulse width modulated AC current from the X ray control board The heated filament cathode emits electrons which are attracted to the anode by a positive potential During transit they gain energy from the electric field which exists between the anode and cathode When the electrons strike the anode they lose this energy by producing both X rays and heat A focusing electrode causes the electrons to impact the anode in a spot about Imm The magnitude of the electron current is controlled by the X ray control board and is limited to 1 98 mA The anode also called the target consists of a thin disk of rhodium or other material plated on a copper block The anode is typically cut such that the angle between the face of the target and the normal to the exit window is 20 The window is made of thin 0 005 beryllium foil which allows X rays to escape and at the same time holds a high vacuum Filament Primary radiation filter Window Sample Figure 4 1 X ray tube schematic Use of the X ray tube in quantitative analysis requires attention to the following three considerations It is important to measure the spectrum from the X ray tube to make sure that the correct target material is used This can be done by observing the scattered spectrum The characteristic K and L lines of the target should be present Slight changes occu
167. les Spectrace Instruments QuanX Technical Manual 7 33 Test and Adjustment Procedures 4 Highlight ANALYSIS TECHNIQUE and press SETUP Change the mode to Standardize Set print statistics to Yes EXIT back so that ANALYSIS TECHNIQUE is highlighted and press RUN 4 The system prints out the difference and relative error for each tray position and an overall sigma value 4 Verify that the sigma value is 0 30 or less and that the relative error for any single position is 0 50 or less 4 If the test fails perform Procedure 7 14 Sample Tray Height Adjustment The correct height greatly minimizes the sensitivity to tray flatness Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 34 7 16 Livetime Scope and purpose To test the pulse processor dead time correction circuit and thus make sure that analysis results are reproducible regardless of the mix of elements in a sample Test equipment Sample cup with copper foil approximately 0 150 diameter disk fixed in place between mylar sheets MnO powder Test conditions Optional The diagnostic diskette contents has been installed and the QUANX program has the active directory set as C SPECTRAC QTESTLN or CASPECTRACIQTESTECD for an LN or ECD system respectively Procedure Note The dead time with and without manganese is critical for this test Steps 1 3 4 amp 5 are included to determine the correct tube current for the particular sample
168. lip lead Reconnect the ECD board J3 connector Connect the power cord Spectrace Instruments QuanX Technical Manual 7 9 Test and Adjustment Procedures 7 5 Latch Adjustment Scope and purpose To adjust the lid latch and interlock switches This is required for proper operation and is also a critical safety related procedure Test equipment Long nose pliers Test conditions The main enclosure cover should be removed Procedure 1 Loosen the screws holding the chamber lid interlock switch large black switch bracket to the baseplate Adjust the switch body position so that the actuator key enters and exits the switch smoothly as the lid is opened and closed Tighten the bracket to baseplate screws 1 Loosen the screws which hold the chamber interlock switch to its bracket Close the chamber lid Push the interlock switch body up until it hits the actuator key plastic trim plate Lower the switch body about 0 1 inch and tighten the screws 1 Loosen the screws which hold the latch assembly to the baseplate Close the chamber lid Energize the latch solenoid using the ECHOA program CTO CX or a 24 volt power supply Rotate the latch assembly to achieve the maximum overlap of the solenoid plunger and the chamber lid tongue while not allowing the collar mounted on the solenoid plunger to hit the chamber lid tongue See Figure 7 2 a below Tighten the screws and de energize the solenoid CTF CX 1 1 Adjust the lock sense switch by
169. lock the chamber lid closed whenever the X rays are on One switch detects if the solenoid plunger has traveled far enough to lock the lid the other switch senses if the chamber lid is closed Both switches must be activated before X rays can be generated Spectrace Instruments QuanX Technical Manual 3 3 Product Description The sample chamber lid is lead lined for radiation safety and is vacuum tight for analysis of low atomic number elements The X RAYS ON warning light is located in the sample chamber lid This light indicates the status of the X ray generator Next to the warning light are the Power On and Detector Temp lights The Power On light is on whenever the AC power switch located on the back of the unit is turned on The Detector Temp light is normally off but will flash if the detector is not at the correct operating temperature For an LN detector this indicates that LN should be added For an ECD this means the detector coolers are not maintaining the proper temperature All the lights are mounted on a PC board called the display board The chamber lid interlock switch is the primary safety interlock device used to prevent X ray generation when the chamber lid is open A second lid interlock switch is part of the lid latch assembly previously described The primary switch uses a Positive Break design the contacts are forced open by a mechanical drive mechanism rather than by a spring as in a normal switch It also f
170. lue should start low achieve a maximum and start dropping as more washers are added The correct tray height is the one with the highest gross count Install the corresponding washers or corrected height tray pads in the chamber Spectrace Instruments QuanX Technical Manual 7 31 Test and Adjustment Procedures 7 15 Sample Tray Accuracy Scope and purpose To verify that the system gives the same results when analyzing the same sample in any position The test uses a set of identical brass plugs analyzes one in each tray position and calculates the deviation in counts between positions Test equipment 20 1 25 identical brass plugs cut from the same bar Test conditions Optional The diagnostic diskette contents has been installed and the QUANX program has the active directory set as C SPECTRAC QTESTLN or C SPECTRAC QTESTECD for an LN or ECD system respectively Procedure 1 Load the standard sample tray with 20 identical brass samples for spinner trays see step 2 1 For systems equipped with the optional sample spinner test the spinner as follows Exit out of the QUANX program Type ECHOA Q to start the communication program Type CBO J CX J Verify that the spinner motor is turning Check that an empty spinner cup turns smoothly in the tray Place a brass sample in the cup and check that it turns smoothly in the tray Press ESC to exit ECHOA Restart the QUANX program 1 Ifthe system only has a 10 position samp
171. ly When ion pump power is lost the housing vacuum will begin to decrease and within 3 hours it can deteriorate to a level at which the ion pump will not function properly when power is reapplied Such a condition should be avoided since it can only be corrected by repair or replacement of the ECD assembly Therefore plan ahead to carry out these procedures in a timely fashion Procedures of this nature contain a cautionary statement Spectrace Instruments QuanX Technical Manual 9 3 Component Replacement 9 3 Circuit Boards Replacement of the PC boards located in the card cage and elsewhere is detailed below 9 3 1 Chamber Control Board 1 See Figure 3 4 for the location of this board 1 Turn off the instrument power switch 1 For ECD systems disconnect the instrument power cord This is required to remove all power from the chamber board socket 1 Remove the board by pulling out on the two ejection ears located on the top of the board Lift the board out of the card cage 1 Set the switches on the replacement board to match the old board settings SW1 and SW2 are normally both set to the SPINNER position unless the system is equipped with an R Theta or Y Theta sample stage in which case both are set to the THETA position SW3 sets the chamber vacuum trip point 1 Install the replacement board by repeating the previous steps in reverse order Press firmly on the board until it snaps into place 9 3 2 Pulse Processor 1 See
172. ly 30 in medium range If high this is the problem Not a comprehensive test substitution is better Verify by substitution replace if required Procedure 9 3 2 Verify by substitution replace if required Procedure 9 3 3 Verify by substitution replace if required Procedure 9 3 4 Turn off the power Disconnect the preamp See Installation cable from the bias supply board portion of For ECD Disconnect the in line connector JI Procedure 9 6 near the ion pump power supply disconnect for hints the ion pump cable from the ion pump disconnect the ECD control board J4 connector Measure the resistance between the detector body and a non painted surface on the chamber wall There should be no continuity infinite resistance If there is continuity locate and eliminate the source Best diagnostic method is process of Procedure 7 11 elimination Watch for drops in the zero width and or fast discriminator values while eliminating possible sources Run resolution test with source removed if possible Remember to reconnect it when done Disconnect the in line connector J1 near the ion pump power supply Spectrace Instruments QuanX Technical Manual 10 30 X ray voltage current control board Noise on AC power line Faulty ADC interface cable Noisy DC power supply Microphonic vibration induced noise pickup caused by An external vibration source Loud external noise source Cooling fan vib
173. m the old to the new tube Note the collimator is not fastened to the tube it may have remained in the chamber wall when the tube was removed Install the tube and shroud by following the previous steps in reverse order Verify that the tube flange depresses the interlock switch lever located on the chamber port Perform Procedure 7 12 Stability If the tube hasn t been operated for a long period an overnight burn in at moderate power may be required to improve its stability 9 7 2 X ray Tube Cooling Fan 1 1 1 See Figure 3 3 for the location of the fan Turn off the instrument power Remove the four rear panel screws which hold the enclosure cover in place Remove the enclosure cover by grasping it on the bottom of each side and sliding it directly forward Detach the flexible hose from the fan duct Spectrace Instruments QuanX Technical Manual 9 19 Component Replacement Disconnect the white in line connectors located in the fan power lead and the X ray tube shroud temperature sensor cable Remove the screws which hold the rubber mounts to the instrument chassis Remove the fan Transfer the duct and rubber mounts from the old fan to the replacement fan Install the replacement fan by following the previous steps in reverse order 9 7 3 Enclosure Cooling Fan 1 1 1 See Figure 3 4 for the location of the fan Turn off the instrument power Disconnect the instrument power cord Remove the four rear panel screw
174. mmunication cable is connected between the PC COMI connector and the QuanX Turn the QuanX power off for 10 seconds and then on again Verify that the filter wheel and sample tray if equipped establish home position correctly the board will not communicate with the PC until the sample tray initialization is complete 1 To exit the program press ESC or CRTL C 8 3 2 Command Language Description ECHOA commands are entered by typing them on the keyboard The commands are classified as either action commands or query commands Action commands initiate actions which change the hardware status such as moving the filter wheel to a new position These commands begin with the letter C Query commands request information on the hardware status such as the sample tray position They begin with the letter Q Action commands are issued by typing the command for the desired function pressing the ENTER key typing CX and pressing the ENTER key again Action commands are not executed until the CX command is entered The following example illustrates an action command to move the filter wheel CF3 ENTER CX ENTER Spectrace Instruments QuanX Technical Manual Diagnostic Software 8 4 A sequence of actions can be initiated by entering several action commands followed by a single CX command In this case each command will be executed in a predetermined order Query commands are issued by typing the appropriate command for the information desi
175. mperature is high Blocked ECD fan vent opening Enclosure temperature is too high ECD fan inlet duct not sealed against inlet wall Disconnected or loose ECD heat sink cooling hose Temperature set point needs adjustment ECD cooler power supply needs adjustment Faulty ECD control board Faulty ECD cooler power supply Poor housing vacuum causing high heat load Remedy Reduce ambient temperature to below 30 C 86 F Vent opening on the left side must have at least 4 inches clearance See Ambient temperature inside the instrument is high Loosen screws and adjust the duct so that the rubber seal touches the enclosure cover when it is installed flexible hos n the heat Check the larg connected betw sink and fan ECD board TP2 should be 3 75V adjust R5 This adjustment sets the base temperature Set the nominal output level with sense lines shorted to output per procedure This setting acts as an offset bias to move the output range higher or lower It doesn t directly set the detector temperature or cooler voltage Verify by substitution Verify by substitution Or if desired test by varying the sense input and verifying that the output voltage changes R5 on ECD control board may be used but must be reset for 3 75V at TP2 See Jon pump current is high Spectrace Instruments QuanX Technical Manual Procedure 9 3 2 Procedure 9 3 4 Procedure 7 4
176. n uoc ee t o e td m al e E IR deoa 3 1 3 2 A Tour HE The QUINN 525 tects vine o 3 2 33 Specifications tesi A eR LP EE es ER sen decease deed 3 12 34 Outline Drawing iiie dea ER eta dtes 3 17 Theory of Operation 4 1 Introduction e e Ie Eee epe d d e e tdeo HORE po cag 4 1 42 X ray TUDE eee fme et ee etie e ep t end ume obese ket pi eise 4 2 4 3 X ray Control BOa docs cis EUREN 4 3 4 4 Safety Interlock Circuit sustento dete pee tre ee 4 5 4 5 Electrically Cooled X ray Detector CID 4 7 4 6 Liquid Nitrogen Cooled X ray Detector nennen rennen 4 9 Al Preamp iier too sn er e ete pe p eu e t ene hoe 4 11 4 8 Chamber Control Board mii E SERA ge ENEE iie 4 12 4 9 Display Board X ray On Warning Lghtt rennen 4 16 4 10 Bias SupplyJBoard EE 4 17 4 11 ADE Interface Boa td 2 oaa tere aem eee 4 19 4 12 ECD Control Board nsn ee ep et ene 4 20 Installation S NIU IO RII 5 1 312 Site Preparation cnr eet A Pete ete b ebrei tet e epe a 5 2 3 3 Special Precautions 3 ete pee see e Lo edicere coded ede as 5 4 SA Quan X Setup aueh tonc pi ev Re eee e REO e Eben 5 5 3 3 Personal Computer Setup eoi ede eo ene Shes 5 7 35 6 Performance Testing Le eder e Be HR CL 5 14 6 Periodic Maintenance Gel Fotto 6 1 6 2 Maintenance Procedures 9 iie etd en eee ier er ene tee 6 2 7 Test and Adjustment Procedures Tl Introducton ime EE de e atc 7 1 7 2 Fast Discriminator Adjustment esses eren eterne enne tense
177. n ISA bus The purpose of the procedure is to set the board address that will be used for communication between the PC and the ADC interface board This address may be different for some systems due to the presence of other interface devices in the PC that conflict with the board address preset at the factory The ADC interface board uses an upper memory block memory mapped address for spectral data transfer and an I O mapped address for control communication between the PC and the ADC board This procedure is used to select a memory mapped address the I O address is fixed at 330H The DOS 5 0 and higher operating systems use the same high memory area as the ADC interface board Due to this after an address is selected the CONFIG SYS file must be modified to prevent DOS from using the memory area chosen for the board The file may be modified using Word processing program or by using the DOS EDIT function To allow the QUANX analysis program to locate the ADC interface board the address selected must be entered in the TXCONFIG program Conditions The computer must be completely assembled and operational Spectrace Instruments QuanX Technical Manual Installation 5 11 In order to perform the final test of the board operation spectral display the entire QuanX system must be connected and operational Required equipment Spectrace Instruments part number 5911 0224 or old version 5911 0181 ADC interface board Safety prec
178. n each side for the cooling fan inlets additional free space for samples or supplies is helpful The area in front of the instrument should be free of obstructions for at least 3 feet 0 9 m to allow removal of the enclosure cover for servicing The QuanX requires about 3 feet 0 9 m of vertical clearance above the table top The personal computer and printer also require an area of about 27 by 36 inches 69 by 91 cm The computer CPU may be installed up to approximately 5 feet 1 5 m away from the QuanX if it is located on the left side or up to approximately 3 feet 0 9 m away if it is located on the right side To avoid possible electrical noise pickup the PC monitor should not be placed closer than 1 foot 0 3 m away from the QuanX Refer to Section 3 4 for a dimensioned outline drawing of the QuanX Ample room for a vacuum pump and or helium gas cylinder will be required if vacuum or helium operation is anticipated The vacuum pump may not be placed on the same table as the QuanX 5 2 4 Vibration The instrument is moderately sensitive to vibration Microphonic noise is generated by capacitive coupling between the internal components of the X ray detector The result is degraded resolution which will adversely affect accuracy and precision Spectrace Instruments QuanX Technical Manual Installation 5 3 Both the amplitude and frequency of the vibration are important factors In general the lower the frequency of vibration the large
179. n sample as an unknown is an excellent N A empirical method of checking instrument performance The sample should be similar to those normally analyzed it should also be mechanically and chemically stable Procedure Comments Number This is an absolute minimum frequency twice a week is N A the preferred fill schedule The dewar should be filled to the bottom of the neck or if filled to the top wait until it boils down to perform quantitative analysis The increased boiling when LN is in the neck area can degrade resolution CAUTION The LN level must be maintained whether or not the system is in use The detector crystal may be damaged by frequent temperature cycling caused by allowing the LN to run out The fast discriminator value is located on the system 7 2 status screen If the FD is set too low the minimum energy limit will be too high causing low energy peaks to be lost If the FD is set too high the dead time readings can be inaccurate and will be higher than normal The FD does not normally require much adjustment Drastic changes 2100 may indicate some other problem with the system Spectrace Instruments QuanX Technical Manual 6 3 6 2 3 Monthly Action Run an overnight stability test Print the system status screens Check the vacuum pump oil level optional equipment 6 2 4 Semiannually Action Perform state mandated safety checks 6 2 5 Annually Action Remove dirt from the air
180. n the window with a cotton swab or to pick debris off of it using tweezers Beryllium metal is also very susceptible to corrosion from water acid or other caustic substances Corrosion destroys the vacuum integrity of the window Do not use cleaning solvents other than those specified without contacting the Customer Service department first Rupture of the window destroys the detector assembly necessitating its complete replacement Replacement due to window damage is not covered under warranty or service contract and costs several thousand dollars Warning Beryllium metal is highly toxic if ingested Do not touch or otherwise handle the foil If the window is ruptured follow the emergency measures in Section 2 4 Poisoning Hazard Beryllium Window Warning Methanol is extremely flammable and toxic Remove all ignition sources from the area before beginning this procedure Follow all local site regulations regarding chemical handling Procedure X ray detector window 1 Remove the sample tray and the metal plate covering the components of the sample chamber Remove the two socket head screws holding the filter wheel assembly in place Move the assembly to the side it is not necessary to disconnect its cables 1 Loosen the nylon screws holding the detector collimator in place Gently remove the collimator Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 52 If the contamination is particulate in
181. nd analysis results To print the graphics images spectrum and calibration curves a compatible graphics printer is required Spectrace Instruments QuanX Technical Manual Installation 5 13 The analysis program requires an IBM Proprinter or equivalent If the printer is not an IBM set it to emulate one of the following models IBM Graphics printer 5152 IBM Proprinter IBM Proprinter II IBM Proprinter X24 Set the printer s Automatic Carriage Return to ON The printer manual may refer to this as Auto CR Virtually all printers including IBM require this change normally the default will be set to OFF Spectrace Instruments QuanX Technical Manual 5 14 Installation 5 6 Performance Testing To ensure that the instrument is operating correctly the following test and adjustment procedures should be carried out in the order listed The detector should have been allowed to cool for at least two hours and the QuanX power switch should have been on for at least 15 minutes The procedures listed may be found in Section 7 Test and Adjustment Procedures 1 Fast discriminator adjustment 1 Interlock test 1 Energy calibration 1 Resolution test 1 Resolution and stability test Spectrace Instruments QuanX Technical Manual DISCARD THIS PAGE Spectrace Instruments QuanX Technical Manual DISCARD THIS PAGE 6 Periodic Maintenance Table of Contents 6 1 Introduction caia da ete etiani i nue etu et 6 1 6 2 Maintenance Pr
182. ng C gt TXCONFIG From the menus presented select MODEL QUANX X RAY SYSTEM OPTIONS SERVICE MODE YES Follow the on screen prompts and exit and save the changes see the QuanX Operators manual for more information on the TXCONFIG program Execute the QUANX program as normal It will now be in the SERVICE MODE and the message SERVICE will be displayed at the bottom of the opening screen To turn off SERVICE MODE exit to the DOS prompt The program will automatically resume normal operation the next time it is executed To continue using SERVICE MODE it must be selected again using TXCONFIG Caution Do not leave the instrument operating unattended in SERVICE MODE Always exit and restart the program to turn off SERVICE MODE after the repair work is completed Unsupervised operation in SERVICE MODE can lead to inaccurate analysis results and or instrument damage Spectrace Instruments QuanX Technical Manual 9 Component Replacement Table of Contents NA EE 9 1 9 2 Special Precautions 2 5S cide ee edie REENEN i ed 9 2 9 3 Circuit e ET 9 3 9 3 I Chamber Control Board menaire eret eet tee n nete e res eh ee Pe EUER HR 9 3 9 3 2 Pulse Processor 45 n ee eere me De ne e e ee 9 3 9 3 3 Bias Supply Board eene Ra ee a e e tee iere E ea 9 3 9 3 4 ADC Boat ET 9 4 9 3 5 Display Doma te ee m ei Waser aie teet een 9 4 9 3 6 X ray Control Bodies 9 5 93 T ECD Control Board xs assed cts eoe tte erit sde oH coda EY PR IEEE ETE 9 5
183. ng System Configuration essere nennen ener nen 5 8 5 5 3 ADC Interface Board Installation eese enne 5 10 3 3 4 Printer COn UTM es e ette eee ier ee da ede ie e deett idee 5 12 5 0 Pertormance Testing ii A eee e e t er E o ee de 5 14 Spectrace Instruments QuanX Technical Manual Installation 5 1 5 1 Introduction Installation of the QuanX analyzer is a straightforward process which may include hardware and software setup as well as operational testing The majority of the task is comprised of performance and functionality testing This section includes site preparation requirements and cautionary notes which if followed will help insure both reliable and stable operation of the QuanX analyzer If the personal computer PC was supplied by Spectrace Instruments the steps related to PC configuration may be skipped However the reader may wish to scan these sections to obtain an overview of the process for future reference The installation process is presented in a hierarchical manner and should be performed in the order presented For example the steps required to cool the X ray detector are presented first so that it will be ready for operation as soon as possible Spectrace Instruments QuanX Technical Manual 5 2 Installation 5 2 Site Preparation Attention to the following recommendations will help insure trouble free operation of the instrument 5 2 1 Location The instrument may be installed on a bench top o
184. ns of an external magnet which causes high energy electrons from previous ionizations to move in spiral paths thus increasing their chance of striking another gas molecule and creating another ion Spectrace Instruments QuanX Technical Manual Theory of Operation 4 8 GROUND N TYPE Si Li COMPENSATED A REGION INS e LL l CK E ww opt S M 4 M C N 2 IOTTKY BARRIER EP CONTACT 200 A Au X RAY S PHOTON Figure 4 2 Si Li X ray detector for the ECD SNC II vm mm 1 PREAMP f A I yy Vy dy dd BEEN J d EUM i Ud d Uy PUMP HEAT SINK II o dd Figure 4 3 ECD X ray detector assembly Spectrace Instruments QuanX Technical Manual 4 9 Theory of Operation 4 6 Liquid Nitrogen Cooled X ray Detector The X ray detector provides the means for sensing fluoresced X ray photons and converting them to electrical signals The detector assembly consists of a Si Li detector which is the X ray sensing device a vacuum tight housing liquid nitrogen to cool the Si Li detector to its operating temperature and a dewar to hold the liquid nitrogen The Si Li detector shown in Figure 4 4 is made from a high purity silicon crystal A bias voltage is applied to electrical contacts on opposite sides of the crystal to produce an electric field throug
185. nt Cu Intensities File number Results Ext program Spectrum processing setup SPECTRUM PROCESSING 1 CU GROSS ROI lt 7400 9400 EV gt Spectrace Instruments QuanX Technical Manual 7 21 Test and Adjustment Procedures Standards file setup STANDARDS FILE ELEMENTS OF INTEREST REPEATABILITY CU FILE NO 200 REL entries 1 to 15 are identical 15 ZERO REF IN Count rate range setup AMP COUNT RATE MEDIUM 4 Highlight ACQUISITION PARAMETERS and press RUN to start the acquisition Answer the prompts as follows No unknowns 10 All others Press ENTER 1 The dead time should be approximately 50 If not press ACQU MENU amp ACQU PARM and adjust the tube current 1 While sample 6 is being acquired press ACQU MENU amp ACQU PARM Change the tube voltage to twice the present value and change the tube current to half of its present value After 15 seconds change the voltage and current back to their original values Wait 20 seconds before pressing EXIT to complete the acquisition of sample 6 1 After the 10 spectra have been stored the system turns off the X rays Highlight SAVE ON DISK and press SETUP Change the file number to 210 press ENTER and EXIT 1 Wait until the X rays have been off for 2 minutes 1 Highlight ACQUISITION PARAMETERS again and press RUN Answer the prompts as follows No samples 5 All others Press ENTER 1 After the 5 spectra have been stored the system turns off
186. o operate properly The table below may be used to determine the detector temperature Resistance Q Temperature C 723 100 743 90 783 80 823 70 903 50 1002 25 1100 0 1197 25 Spectrace Instruments QuanX Technical Manual 7 51 Test and Adjustment Procedures 7 25 Beryllium Window Cleaning Procedure Scope and purpose This procedure is intended for use only when absolutely required such as when the instrument is useless for analytical purposes due to window contamination It should not be performed as routine or preventative maintenance Be sure to read the precautions carefully as a very real risk of serious and expensive instrument damage exists Please contact the Spectrace Instruments Customer Service department for advise and assistance if any questions remain after reading the procedure The procedure is presented in two parts one for the X ray detector window and one for the X ray tube window Conditions No open flames or other ignition sources may be in the area Required equipment Laboratory grade aerosol can of air Methanol in a small squirt bottle Safety precautions The beryllium window on the X ray detector assembly is approximately 0 00035 inches 9 microns thick about one tenth the thickness of this sheet of paper It is also under one atmosphere of pressure since the detector housing is evacuated THE WINDOW IS HIGHLY FRAGILE AND WILL BE DESTROYED BY ANY PHYSICAL CONTACT Do not attempt to clea
187. o the replacement unit if it didn t come with one installed If the o ring is dirty clean it off and reapply a thin coat of vacuum grease Transfer the insulator ring from the old unit to the replacement unit Apply a few spots of vacuum grease to the underside of the insulator ring align the holes in the ring with the flange screw holes and press it into place The grease will hold the ring in place making the final installation easier Transfer the collimator and heat sink shroud from the old unit to the replacement unit if required Install the detector assembly Verify that its flange depresses the interlock switch lever located on the chamber port Install the four screws which hold the flange to the chamber baseplate The screws must have nylon shoulder insulators around them Tighten the screws evenly Before connecting the preamp cable ion pump cable or ECD board J4 cable use an ohmmeter to measure the resistance between the detector body and chassis ground There must be no electrical contact open or infinite reading If there is electrical contact make Spectrace Instruments QuanX Technical Manual 9 17 Component Replacement sure the preamp cable housing isn t touching ground The cause of the short must be found and corrected before continuing 1 Connect the preamp cable to the bias supply board 1 Install the ECD support tray Verify that its rear tab engaged its mating slot and secure the tray to the chassis
188. ocedures ccccccssssssccsccccccsesscsseccccccsvsesescccccessenssescocceeseassnscoccceseascssvcsccees 6 2 6 22 DETI PARLE ete tote ett eiie cere et AR A te 6 2 622 Weekly 24 608 eie etd b ust b ti cs M Aen 6 2 6 2 3 Mohthly pre ien lotte e o cbe eet AN 6 3 6 2 4 Semid unnually E 6 3 6 2 5 Amma tt teste ete pee E i utet oec ote chests 6 3 Spectrace Instruments QuanX Technical Manual 6 1 Periodic Maintenance 6 1 Introduction The QuanX analyzer is inherently a low maintenance instrument The maintenance procedures prescribed in this section and in the Operators manual are of a preventative nature By periodically performing inspections unscheduled down time will be reduced This section does not include procedures for application related operational maintenance tasks such as standardization of the instrument Refer to the QuanX Operators manual and or an applications specialist for information on operational maintenance The maintenance requirements are presented by frequency of service Spectrace Instruments QuanX Technical Manual Periodic Maintenance 6 2 6 2 Maintenance Procedures 6 2 1 Daily Action Energy calibration Run a check standard 6 22 Weekly Action Fill LN dewar Gf applicable Check fast discriminator adjustment Procedure Comments Number Failure to calibrate daily may result in inaccurate 7 3 quantitative results and cause peaks to not line up with KLM markers Running a know
189. of unknowns The dead time should be 15 to 2096 If not the size of the copper foil must be adjusted and the test restarted 3 Highlight SAVE ON DISK and press SETUP Change the save on disk number to 401 Press EXIT 3 Return the manganese to the sample cup Make sure the Cu foil and or the cup is not moved when the Mn is poured in otherwise the test must be started over 3 Highlight ACQUISITION PARAMETERS and press RUN Enter 1 for the number of unknowns 3 Change the save on disk number back to 400 3 Highlight SPECTRUM PROCESSING and press RUN Enter 2 for the number of samples to run 3 Highlight ANALYSIS TECHNIQUE and press RUN The system will print the Cu gross counts for each run 3 Calculate the percent deviation of gross counts between the two runs using the formula run run2 Percent deviation x 100 runi 3 Verify that the percent deviation is 3 0 or less Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 36 7 17 Pileup Scope and purpose To test the pulse processor pile up rejection circuit This circuit reduces artifact peaks known as sum peaks Test equipment MnO sample Test conditions Optional The diagnostic diskette contents has been installed and the QUANX program has the active directory set as C SPECTRAC QTESTLN or CASPECTRACIQTESTECD for an LN or ECD system respectively Procedure 1 Place the MnO sample in tray posit
190. oise pickup or a faulty pulse processor board Refer to the Troubleshooting section of this manual to diagnose the source of poor stability Spectrace Instruments QuanX Technical Manual 7 25 Test and Adjustment Procedures Normal Operation ROI ROI Peak Shift Poor Resolution Figure 7 9 Sources of poor PEAK stability Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 26 7 13 Repeatability Scope and purpose To check that the output of the X ray tube returns to the same level for a given kV and mA setting when the system is turned off and on or momentarily set to different values Test equipment Copper sample Test conditions Optional The diagnostic diskette contents has been installed and the QUANX program has the active directory set as C SPECTRAC QTESTLN or C SPECTRAC QTESTECD for an LN or ECD system respectively Procedure 1 Remove the sample tray and install the single sample holder 1 Place a copper sample in position 1 Select the REPEATABILITY TEST from the procedure menu and press SETUP or set the following conditions Overall setup ACQUISITION PARAMETERS ANALYSIS TECHNIQUE Tube voltage 20kV Method Linear Tube current 0 06 mA 0 12 ECD Mode Run unknowns Filter used Pd medium Std file 200 Livetime 60 sec Preset count Ok Max energy 10keV Atmosphere Air Warmup 10sec SPECTRUM PROCESSING SAVE ON DISK Ref file no 200 Spectrum Elements of i
191. on Spectral Display Output Automation Spectrum Processing Analysis Techniques Operating System Product Description 3 14 IBM PC AT compatible 80486DX 33 or better CPU 8 MB RAM Fixed disk drive 1 44 MB 3 5 inch floppy disk drive VGA monitor 101 key keyboard Operating system MS DOS 6 0 and Microsoft Windows version 3 1 or higher Two RS 232C serial ports 28 800 bps modem Graphics printer IBM Proprinter compatible Soft key menu selection X ray spectrum linear or log procedure title sample identification kV mA filter KLM markers peak labels energy cursor energy scale gross or net intensity of region of interest preset live time elapsed time dead time and overlap comparison of two spectra VGA display graphics printer X ray tube high voltage and current filter selection analysis and output Automatic element identification background removal by digital filter empirical peak unfolding by least squares fitting gross peak intensities and net peak intensities above background Peak ratios linear fit quadratic fit intensity matrix correction and two concentration matrix corrections Normalization to a check standard and display plots of calibration curves are included A fundamental parameters program provides analysis with or without standards Standards may be pure elements or compound standards of a matrix similar to the unknown MS DOS version
192. on describes Spectrace Instruments service practices the organization of this manual additional Spectrace or OEM documentation and other information of general interest Section 2 Safety This section is a compilation and explanation of safety notices and precautions applicable to the instrument Section 3 Product Description This section provides an overview of the instrument and a summary of its specifications Section 4 Theory of Operation This section provides a functional description of the instrument Section 5 Installation This section contains instructions for the mechanical assembly software installation and testing necessary for proper installation of the instrument Section 6 Maintenance This section contains a program for maintenance of the instrument including items requiring service the applicable procedures and tests for verifying proper operation Section 7 Test and Adjustment Procedures This section contains detailed procedures for the adjustment calibration and testing of the instrument and its component modules Section 8 Diagnostic Software This section describes the diagnostic software used as part of the various service procedures Section 9 Component Replacement This section contains detailed instructions for component replacement Section 10 Troubleshooting This section contains a list of error messages and a guide to troubleshooting presented as a table of symptoms causes and remed
193. operation and installation This circuit monitors the detector leakage and disables the detector bias if the current exceeds safe limits regardless of the origin of the high current In the ECD version only a high detector temperature alarm low LN alarm will also turn off the detector bias The magnitude of the leakage current is deduced from the preamplifier reset pulse rate as it is proportional to the current The reset pulses are averaged by and R C integrator R45 and C35 If this average value exceeds a predetermined limit the output of U7 switches to zero volts and the output of U6 switches high A high output from U6 turns off the front panel HV LED and stops the oscillator by switching Q2 on When the excessive leakage current stops the output of U7 switches high and U6 provides about a one second delay before the oscillator is restarted Liquid nitrogen level monitor The same circuit is used for low LN warning and high ECD temperature The board front panel LED is labeled LN LEVEL in both cases and is on when the LN level or ECD temperature is normal or flashes when the LN level is low or the ECD temperature is high LN version Spectrace Instruments QuanX Technical Manual Theory of Operation 4 18 The liquid nitrogen level monitor provides a visual and an audible alarm whenever the detector dewar needs refilling When the liquid nitrogen level falls below the sensor the sensor resistance increases U8 senses this increas
194. or so that the zero DAC reads 10 or less 1 Press EXIT to return to the MAIN menu and press EXIT again to go the PROCEDURE menu 1 Press ENRGY CALIB the system begins an acquisition Press ACQU MENU SYS STAT COUNT RATE and set the pulse processor to the Medium range or the range most often used for analysis Press EXIT Type CU and press Enter to display the KLM markers for the K lines of copper Position the cursor near the K alpha line at 8 041 keV Expand the display until the Cu K alpha peak fills the screen Select the ACQ MENU and display the secondary acquisition soft keys Press ZERO GAIN and thereby reset the gain DAC to zero If the Cu peak is close to the marker the system automatically readjusts the gain DAC to bring the peak closer to the marker p REO m E E 1 If the Cu spectrum is very far out of adjustment as illustrated in Figure 7 8 then adjust the COARSE and FINE gain pots on the pulse processor until the Cu peaks are lined up with the KLM markers Spectrace Instruments QuanX Technical Manual 7 17 Test and Adjustment Procedures Cu Cu Figure 7 8 System out of calibration 12 Press ZERO GAIN and RESTART to start another acquisition 1 Repeat this cycle ZERO GAIN adjust RESTART until the gain DAC is less than 50eV when the calibration routine stops automatically or when the ERROR is less than 2 Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 18 7
195. ot set to number of postions 1 this will generate the configuration error message when QUANX is run Faulty chamber control board or Verify by substitution Procedure 9 3 1 stepper motor and 9 5 2 SPECTRUM CONTAINS PERIODIC ERRORS Cause Remedy Reference Address conflict between the ADC Change the address used for the ADC Procedure interface board and some other interface board per procedure 5 53 device in the personal computer Faulty ADC interface board Verify by substitution replace if required Procedure 9 3 8 Faulty ADC interface cable Verify by substitution replace if required STRAY LINES UNWANTED ELEMENTS APPEAR IN THE SPECTRUM Cause Remedy Reference Sample contamination Test with a known clean sample Detector collimator is not installed or The collimator should be oriented so that the is incorrectly installed snout flat area is horizontal A small amount of background Verify if the contamination is beyond Procedure 7 18 contamination is normal specifications by running the test procedure Filter wheel positioning error Select the no filter position and verify visually that the filter wheel opening is approximately centered over the X ray tube collimator hole Centering is adjusted by moving the home sensor Spectrace Instruments QuanX Technical Manual 10 32 Sample tray positioning error X ray tube sourced contamination Contamination of the detector s beryllium window Fault
196. placement 1 Remove the X ray high voltage power supply as described in Procedure 9 4 1 1 Remove the screw that secures the front of the power supply tray to the enclosure 1 Disconnect the two white in line connectors J5 amp J6 located on left side of the power supply tray This allows the tray to slide forward farther 1 Flip up the radiation shield Slide the tray forward Free cables as required to allow about 1 3 of the tray to protrude 1 Remove the perforated metal shield from the tray assembly 1 Disconnect the power supply s AC connector a white in line connector labeled J1 located between PS3 and PS4 1 Rotate the tray 90 degrees clockwise Remove the screws securing the power supply to the tray 1 Remove the green yellow wire safety ground wire from the supply chassis 1 Install the replacement supply by executing the previous steps in reverse order Do not install the enclosure cover 1 Check or adjust the supply outputs per Procedure 7 4 Power Supply Test and Adjustment 1 Install the enclosure cover 9 4 5 PS4 24V Linear 1 See Figure 7 3 for the location of this supply Turn off the instrument power Disconnect the instrument power cord Remove the four rear panel screws which hold the enclosure cover in place Remove the enclosure cover by grasping it on the bottom of each side and sliding it directly forward 1 Remove the X ray high voltage power supply as described in Procedure 9 4 1
197. r in the position and dimension of the filament and other internal dimensions as the tube warms up to its equilibrium temperature These changes may affect the intensity distribution of the primary beam It is thus important to wait half an hour at operating voltage and current before making precise quantitative measurements The output flux of the X ray tube at constant kV and mA decreases approximately 3 for each 1000 hours of operation due to pitting and sublimation of target material on the inside of the tube window To obtain accurate results this effect should be calibrated out Spectrace Instruments QuanX Technical Manual 4 3 Theory of Operation 4 3 X ray Control Board The X ray control board part number 5911 0220 schematic no 5919 0161 controls the voltage and current applied to the X ray tube It is able to control both 30kV and 50kV X ray power supplies for currents up to 1 98 mA Control Interface Tube current and voltage settings are transmitted to the X ray control board via a 3 wire serial interface The three lines WRI STR and DATA connect to optoisolators U3 U4 and U5 respectively Information is sent as 8 bit words with the most significant bit MSB first The MSB indicates whether the word is a current or voltage value the other seven bits are the value A pulse occurs on the STR line for each bit and clocks the DATA signal into serial to parallel converter U7 When all eight bits have been received a pulse on
198. r on a dedicated stand In either case the structure should be strong enough to support 200 pounds 91 kg and remain very stable Any movement of the structure such as wobbling or vibration can not be tolerated A low traffic area is recommended to prevent bumping or other disturbances while the instrument is in use 5 2 2 Atmosphere The beryllium windows of the detector assembly and X ray tube are susceptible to damage from corrosion This type of damage is always catastrophic requiring the complete replacement of the detector or tube Do not store or operate the equipment in a high humidity above 8076 RH or a corrosive atmosphere such as a coastal receiving dock or near a process emitting corrosive fumes Please contact our sales or applications staff for recommendations if analysis of corrosive samples is required This is critical since caustic fumes can destroy the detector window in a matter of minutes Excessive dust or dirt should be avoided Internal components will become coated with dirt which may lead to overheating Electrically conductive particles such as metal dust must not be present in the operating environment f the instrument is to be operated in a dirty environment special fan filters must be installed Please contact your sales person for details 5 2 3 Space Requirements The QuanX requires a rectangular area of about 27 by 36 inches 69 by 91 cm which includes the minimum 4 inch 10 cm clearance required o
199. r the amplitude required to produce noticeable degradation A rough rule of thumb is if you can feel the vibration with your hand it may be a problem Potential sources of vibration are e Heavy machinery operating nearby e Raised floors with vibrating equipment in the room e Other equipment placed on or in contact with the table such as the vacuum pump e Very loud noise 5 2 5 Temperature The instrument is designed to operate over a temperature range of 32 to 86 F 0 to 30 C for the ECD version or up to 93 F 34 C for the LN version For maximum precision the room temperature should be stable Operation over large temperature swings may require restandardization of the instrument to meet sensitive application precision requirements 5 2 6 Power Requirements The instrument may be set to operate on either 115 or 230 VAC 50 60 Hz AC power The maximum power required is 350 watts for the LN version and 500 watts for the ECD version The personal computer and the QuanX should be plugged into the same outlet The optional vacuum pump requires 700 watts and may be operated from a separate power source the QuanX has a second power cord dedicated to vacuum pump operation The ECD version requires continuous uninterrupted power Loss of AC power for more than 72 hours may cause serious damage to the X ray detector assembly A dedicated power line is recommended since it helps isolate the analyzer from electrical disturbances caused
200. race Instruments QuanX Technical Manual 11 5 Optional Equipment 9 Options Schematic Assembly Title 9100 4918 R Theta 2 Stage 8100 7454 Y Theta Motorized Table 8100 7455 Y Theta Slide 9100 4915 Y Theta Stage 9100 4922 X Y Stage Spectrace Instruments QuanX Technical Manual Optional Equipment Spectrace Instruments QuanX Technical Manual 10
201. ration Faulty detector preamp board Faulty detector assembly Troubleshooting Disconnect J2 from the board 5919 0161 Use a power analyzer install a power conditioner or run the system from an alternate source to verify Verify by substitution replace if required Verify by substitution of the power supply is best Unplug the PS2 AC plug and watch for zero width drop will turn off coolers on ECD systems so go fast Best diagnostic method is process of Procedure elimination Watch for drops in the zero 8 2 6 width and or fast discriminator values while eliminating possible sources Run resolution test with source removed if possible The system should be on a stable floor No rigid connections between the enclosure and a vibration source are allowed The detector is sensitive to acoustic vibration Eliminate the source of the noise or provide sound and vibration isolation for the instrument Verify by disconnecting power to the fan The X ray tube fan has a connector The enclosure fan has wires in motherboard J7 Verify by substitution replace if required Contact factory Verify by substitution replace if required Procedure 9 6 SAMPLE TRAY FAILED TO LOCATE HOME CONFIGURATON ERROR OPTIONS DON T MATCH TXCONFIG SETTING Cause Mechanical jam Motor or sensor connector is unplugged or a wire is broken If the tray turns when the power is turned on see the following causes Sample home
202. ratures It acts as a sponge to adsorb gas molecules which remain bonded to the surface as long as the low temperature is maintained After several years the carbon becomes saturated and the dewar must be reevacuated TYPE Si i Li COMPENSATED E REGION XY T d X C N d A Tf B N cn DETECTOR gt SCHOTTKY BARRIER a TRES CONTACT 200 Au PHOTON Figure 4 4 Si Li X ray detector for the LN model Spectrace Instruments QuanX Technical Manual Theory of Operation 4 10 VEL SENSOR _ DETECTOR FET A ve ss 2 PREAMPL ACTIVATED CARBON Figure 4 5 LN X ray detector assembly Spectrace Instruments QuanX Technical Manual 4 11 Theory of Operation 4 7 Preamplifier The pulsed optical preamplifier and related components are shown in Figure 4 6 and schematic 0110 0609 The FET and the amplifier are in a negative feedback configuration Cf acts as the integrating capacitor so output is proportional to the integrated charge Detection of an X ray photon will produce a fast positive step in the output The amplitude of this step is proportional to the photon s energy Since the X ray flux from the sample consists of many photons with varying energy the preamp output looks like a stair case with varying step heights In order to keep the preamplifier s output within its linear range a pulsed optical feed
203. rboard access panel from the back panel of the instrument 1 Plugin the power cord and turn the unit on Use the DMM to measure the voltages on the motherboard connector J3 as shown in Figure 7 2 Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 6 20 1 J3 METER GROUND Figure 7 2 Motherboard rear view J3 VOLTAGE V 5 15 to 5 25 0 gnd 11 5 to 12 5 0 gnd 9 11 5 to 12 5 10 23 8 to 24 2 11 0 gnd 12 11 9 to 12 1 13 11 9 to 12 1 14 0 gnd 15 23 8 to 24 2 16 23 8 to 24 2 17 0 gnd 18 20 no connection Remove the enclosure cover POWER SUPPLY PS1 PS1 not adjustable PS1 not adjustable PS2B PS3 PS4 Measure the voltage on the 24 volt switching power supply PS2 On dual output versions black body measure output A threaded studs On single output versions silver body measure any orange wire on the output terminal block The location of PS2 is shown in Figure 7 3 The voltage should be 25 25 to 25 35 The adjustment points for the dual output version of PS2 are shown in Figure 7 4 The single output version has a single adjustment pot above the output terminal block mm wu 53 12 switching a i N PS4 C 41 24 linear 24 switching PS2A8B PS3 i o e 4 12 linear Figure 7 3 Power supply tray top view Spectrace Instruments QuanX Technic
204. reas of the spectrum will drop approximately 1 This includes the area under the copper peak as well as the background in the rest of the spectrum The entire spectrum is represented by the TOTAL value Conversely a problem in the X ray detection system will affect the copper peak counts to a much greater degree than the rest of the spectrum This can best be explained by example The two most common X ray detection problems which cause poor precision are peak shift and unstable resolution peak width These conditions are shown in Figure 7 9 In the case of peak shift less copper counts fall within the region of interest ROI boundaries therefore the reported PEAK counts decrease In the poor resolution case the peak width increases and since the total number of copper X rays hasn t changed peak area is the same the peak is shorter and therefore less copper counts fall within the ROI In both cases the PEAK counts drop while the TOTAL counts remain constant In summary the interpretation of the test results rely on the following logic TOTAL deviation affects the PEAK but PEAK deviation does not affect the TOTAL If the TOTAL stability is poor items such as the X ray tube X ray high voltage power supply or the X ray control board are suspect If the PEAK stability is poor and the TOTAL is good look at the peak centroid and FWHM resolution columns to isolate the source Peak instability is most often associated with detector problems n
205. red and pressing the ENTER key CX is not required The response to a query will start with the letter A for answer The following example illustrates a query command to determine the filter position QF ENTER evokes the response AF3 indicating that the filter is in the logical position 3 physical position 4 8 3 3 ECHOA Command List Comman Name Usage Error Usage Description d Response action CA Vacuum pump CAO EHO Turn vacuum pump ON control CAF Turn vacuum pump OFF CB Sample spinner CBO Turn sample spinner ON control CBF Turn sample spinner OFF CCI Set tube current CCIxx MAX Set tube current to 0 xx x2 mA xx 00 to 99 QuanX doubles xx value CCH Set high voltage CCHx MAX Set tube voltage to xx kV x xx 04 to 50 CD Low flow helium CDO EAO Turn low flow helium ON control CDF Turn low flow helium OFF CF Set filter position CFx MAX Set filter to pos x 1 x 20 7 CH High flow helium CHO EAO Turn high flow helium ON control CHF Turn high flow helium OFF CL Turn OFF ON CLO Coolers ON coolers CLF Coolers OFF CP X ray power CPO INT ET X ray power ON F CPF ELID X ray power OFF Spectrace Instruments QuanX Technical Manual 8 5 Comman d action CR CS CS CT CX CY if supported CZ Comman d query QA QB QCH QCI QD Name Chamber vent control up to air valve Set sample tray position 0127 amp 0128 ROM Set RTheta linear position 0129 ROM Chamber lid latch
206. rious components in the QuanX The special precautions section as well as the specific procedure for the component of interest should be read before beginning the actual repair work This will provide insight on the scope of the task and allow the service technician to properly plan the time and materials required Spectrace Instruments QuanX Technical Manual Component Replacement 9 2 9 2 Special Precautions Beryllium windows The X ray tube and ECD detector both have beryllium windows which are extremely fragile and brittle Since beryllium metal is highly toxic do not touch or otherwise handle the foil DO NOT touch jar or subject the beryllium windows to mechanical or thermal shock or to corrosive substances When installing replacing or working around the X ray tube and the detector assemblies proceed with great caution Refer to Section 2 Safety for more information on beryllium hazards Ion pump power ECD model only The ECD detector assembly must be maintained at a high vacuum This vacuum is maintained by the continuous operation of an ion pump Power for this pump normally comes from the AC line or from the internal backup battery if the instrument is not plugged in A fully charged battery will support the ion pump for 72 hours do not allow the instrument to remain unplugged longer than this during component replacement operations Some of the following procedures require disconnecting power from the ion pump power supp
207. roduct Description Si Li 15mm area lt 175eV FWHM resolution for 5 9keV X rays at 1 000 cps lt 14 0 micron 0 55 mil Beryllium Be Thermoelectric Peltier and air Pulsed optical reset Backup battery for vacuum pump is a sealed design Yuasa NP 7 12 7 0Ah or equivalent Si Li 30mm area lt 155eV FWHM resolution for 5 9keV X rays at 1 000 cps 8 9 micron 0 35 mil Beryllium Be Liquid nitrogen 8 liter capacity dewar 1 liter day consumption Pulsed optical reset Shaping network time variant Stability 0 01 C Integral linearity 0 1 Pileup rejecter pulse pair resolution is 250 nanoseconds above 2 5 keV and 1 microsecond below 2 5 keV Live time correction 1 0 from 0 to 20 kcps Computer selected time constants Resolution degradation with count rate in a given count rate range is negligible in time variant pulse processors 4 096 addresses 100 MHz clock automated energy calibration and zero correction 2 048 data channels 16 million counts channel 8 bit ISA bus compatible full length slot The data memory is the interface to the computer Requires a 16k contiguous memory block within the C0000H to EFFFFH range I O map addresses used are 330H to 333H no IRQ interrupts used Power consumption 5V DC 1 2 A Spectrace Instruments QuanX Technical Manual DATA PROCESSOR Computer Typical specifications The PC may be user supplied SOFTWARE Operati
208. rom the ECD cooler supply chassis This is the ground wire with a dedicated screw not the ground wire using a transformer screw Loosen the hose clamp holding the air hose to the ECD heat sink shroud Disconnect the hose Turn off the ion pump power supply by disconnecting the white in line J1 connector located near the supply The red LED located on the lower part of the bracket should turn off Disconnect the cable from the ECD ion pump Slide the entire ECD support tray out as one assembly Remove the sample tray and the metal plate which covers the sample chamber components or the special sample handling stage if installed The cover plate is secured with special vented screws save these for reuse Remove the two socket head screws which fasten the filter wheel assembly to the baseplate Move the assembly aside it is not necessary to disconnect its cables Remove the sample spinner drive assembly if installed screws and move it aside It is not necessary to disconnect its cable Remove the four screws which attach the detector to the sample chamber baseplate These screws have nylon insulators under them and are accessed from inside the sample chamber DO NOT remove any screws from the detector assembly itself as this will break its vacuum seal Support the detector with one hand while removing the last screw DO NOT allow the detector assembly to drop Remove the ECD Installation 1 Transfer the o ring from the old unit t
209. rovided on PS5 An offset signal is generated by U4 which is connected to one side of the R2 R3 resistor divider network The other side is connected to the supply output The power supply will vary its output until the output of the divider connected to the sense input via J3 pin 3 equals an internal reference voltage This causes the power supply to raise or lower its output voltage in response to the U4 output The U4 output is derived from the temperature of the base via a NTC thermistor mounted to it The thermistor forms half of a voltage divider with R1 as the other half The output voltage is buffered by half of U4 increase in temperature drop in U4 pin 7 voltage R5 is used to set the detector temperature by changing the U4 output voltage The external cooler voltage is also routed through K1 and goes out to the ECD on J4 pin 4 Alarms and status signals Several signals are monitored by the analysis program via the chamber control board Four LEDs are include on this board to give a visual indication of some of these signals they are called DS1 BASE DRIVE OK DS2 COOLERS ON DS3 HEAT SINK OK and DS4 I P CURRENT OK The LEDs are all on during normal operation The external cooler voltage rises as cooling demand increases such as when the ambient temperature increases Other causes of increased voltage may indicate a problem developing and therefore an early warning signal called BASE DRIVE OK is provided This signal goes high when
210. ry set as C SPECTRAC QTESTLN or CASPECTRACWQTESTECD for an LN or ECD system respectively Procedure 1 Start with the stage installed at the minimum height no washers 1 Place the brass or copper sample in tray position 1E using the single sample frame support 1 Select the TRAY ACCURACY test from the procedure menu and press SETUP or set up the following conditions Overall setup using MEDIUM count rate range ACQUISITION PARAMETERS ANALYSIS TECHNIQUE Tube voltage 20kV Method Linear Tube current 0 20 mA 0 40 ECD Mode Run unknowns Filter used Pd thin Std File 300 Livetime 100 sec Preset count Ok Max energy 20keV Atmosphere Air Warmup Do Ssec SPECTRUM PROCESSING SAVE ON DISK Ref file no 300 Spectrum Elements of int Brass Intensities File number Results Ext program Spectrum processing setup SPECTRUM PROCESSING 1 BRASS GROSS ROI lt 7200 10080 EV gt Spectrace Instruments QuanX Technical Manual Optional Equipment 11 5 4 Highlight ACQUISITION PARAMETERS and press RUN Answer 1 for the number of unknowns to run 1 The dead time should be approximately 50 If not press ACQU MENU amp ACQU PAR and adjust the tube current 1 After the acquisition is complete highlight SPECTRUM PROCESSING and press RUN Answer 1 for the number of samples to run 1 Display the spectrum by pressing DISP SPEC then typing C to select the current spectrum Write down the value of the
211. s For either model the detector requires approximately two hours to reach operating temperature 1 Unpack the personal computer PC and place it near the QuanX The computer monitor should not be closer than 1 foot 0 3 meter from the QuanX if possible Connect the 9 pin RS 232 serial communication cable to the QuanX rear panel connector and to the PC COMI port If the computer has a 25 pin COMI connector a DB9M DB25F adapter will be required 1 Connect the ADC interface cable to the ADC interface board installed in the PC If the PC was not supplied by Spectrace Instruments this board must be installed by following the procedure given below in Section 5 5 Personal Computer Setup If this is the case continue with the QuanX setup and connect the ADC interface cable later Spectrace Instruments QuanX Technical Manual 5 6 Installation 1 Open the sample chamber lid Turn on the QuanX power switch and verify that the following operations occur The filter wheel should rotate reverse direction one or more times quickly and stop The sample tray if installed should do the same and stop with position 1 toward the front If the filter and sample tray do not initialize correctly try turning off the power unplugging the power cord and removing and reinstalling the chamber control board rear most board in the card cage Note An alarm will sound when the power switch is turned on if the detector has not yet cooled sufficiently Th
212. s a 7 2 Fast Discriminator Adjustment b 7 9 Initial Energy Calibration c 7 3 Energy Calibration d 7 11 Resolution e System standardization is required before beginning quantitative analysis 9 6 2 Electrically Cooled Detector ECD CAUTION The detector s beryllium window is extremely fragile Read the precautions at the beginning of this chapter before continuing CAUTION This procedure will cause the ECD ion pump to turn off The procedure should be carried out in 30 minutes or less Removal 1 Turn off the instrument power Disconnect the instrument power cord 1 Remove the four rear panel screws which hold the enclosure cover in place Remove the enclosure cover by grasping it on the bottom of each side and sliding it directly forward 1 Remove the screws securing the top left frame member to the chassis and remove the frame member 1 Remove the single screw which holds the ECD support tray to the bottom of the chassis 1 Disconnect the preamp cable connector from the bias supply board located in the card cage Spectrace Instruments QuanX Technical Manual Component Replacement 9 16 Disconnect the ECD support tray cables from the motherboard connectors J11 J13 and J14 located behind the card cage Disconnect the J4 connector from the ECD control board Disconnect the white in line connector J1 located in the ECD cooler supply s transformer cable Remove the green yellow wire safety ground wire f
213. s low and relay K2 is energized A flip flop is used so that a new X RAY ON command is required to restart the X rays after an interlock has been broken The output of relay K2 is then at 24V and is called ENABLE LAMP This voltage does two things First it powers the X RAY ON warning sign located on the 5911 0218 display board Second it provides power for the coils of relays K1 and K3 so that they may be energized later The coils are wired this way so that the relays can t be energized such as by a failed drive circuit unless the computer has issued an X ray on command The return current from the warning light powered by ENABLE LAMP 24V flows through R112 The voltage generated is tested by U22B and C If the voltage is lower than LOW REF warning light is off or only partially on or if the voltage is above HIGH REF warning light LED segment is shorted then the X rays will not turn on If the voltage is within the correct range then U25 pin 11 will go high and if the LID OK signal is high lid is closed and locked then K1 is energized and the X rays turn on In detail the INTERIN voltage from the interlock switches goes through K1 and then through K3 and out J1 54 where it is called INTEROUT This voltage is the power source for the X ray high voltage power supply So the interlock switches and relays K1 and K3 are all in series and must be closed to route power to the H V block The INTEROUT voltage is divided down and buffered
214. s not inserted correctly Faulty power supply or adjustment required Faulty bias supply module Faulty detector preamp board Bias supply module HV light is on but no bias voltage is generated due to a faulty bias supply module Remedy Connect preamp cable Fill the dewar wait 1 2 hours Verify on the ECD STATUS screen The switch is located on the ECD control board If the switch is already in the on position see the following causes Allow 2 hours for the detector to reach operating temperature Verify on the ECD STATUS screen detector should be less than 190 K Or measure per procedure If high see Detector temperature is too high Verify that the light on the bias supply module is off If itis on skip the next 4 causes Turn off the power and reseat the board in the card cage Check the 12 V PS3 using the GENERAL STATUS screen or per procedure Verify by substitution replace if required Verify by substitution replace if required Verify on the GENERAL STATUS screen If good bias supply 1v is greater than 0 95 If low replace the bias supply module DETECTOR TEMPERATURE IS TOO HIGH ECD Cause The detector coolers are not on The detector coolers have not been on long enough Remedy Verify on the ECD STATUS screen An on off switch is located on the ECD control board If the switch is already in the on position see the following causes Allow 2 hours for the detector
215. s the sample tray rotation It consists of a step motor drive belt and optical position sensor The motor is controlled by the chamber control board located in the card cage The assembly may be easily removed or installed as a single unit The vented screws are used in several locations inside the sample chamber These screws have a hole drilled along the axis of the screw The hole allows trapped air to escape quickly from the bottom of the screw hole when the vacuum pump is turned on This eliminates the virtual leak caused by trapped air and significantly reduces the chamber pump down time The filter wheel assembly is an eight position turret driven by a step motor An optical sensor is used to detect the rotational position Each position on the wheel may hold one transmission filter The filters are used to modify the characteristics of the primary X ray beam emitted from the X ray tube and are selected based on the elements being analyzed The motor is controlled by the chamber control board located in the card cage This assembly may be easily removed or installed as a single unit The X ray tube collimator serves to limit the X ray beam size The X ray tube beryllium window is located just inside the collimator opening CAUTION The beryllium window is extremely fragile and can be broken by the lightest touch Never put anything down the collimator shaft or touch this window in any way If the window becomes contaminated contact Spectr
216. s which hold the enclosure cover in place Remove the enclosure cover by grasping it on the bottom of each side and sliding it directly forward Remove the fan temperature sensor from the front of the card cage Remove all the PC boards from the card cage The card cage needs to be loose to create access space Remove the four screws which fasten the card cage to the floor These are the screws with the large clearance holes in the motherboard The screws on the right side may be accessed by using a long screwdriver from inside the card cage Detach the flexible hose from the fan duct Remove the three rear panel screws that hold the fan to the rear panel These are not the screws that hold the finger guard but are the three closest to it Push the card cage forward and work the fan and duct out of the instrument Transfer the duct and rubber mounts from the old fan to the replacement fan Install the fan by following the previous steps in reverse order When complete verify that the fan screw heads do not touch the card cage This could transmit vibration to the detector and cause poor resolution 9 7 4 Sample Chamber Lid Latch Assembly 1 1 1 See Figure 3 2 for the location of the assembly Turn off the instrument power Remove the four rear panel screws which hold the enclosure cover in place Remove the enclosure cover by grasping it on the bottom of each side and sliding it directly forward Disconnect the two switch conne
217. section if the option was installed at the factory The below section 11 5 2 1 is to retro fit system that has ECD or 30mm LN detectors otherwise skip to section 11 5 2 4 11 5 2 1 Installing the Detector Adapter Ring In order to accommodate an X Y stage the ECD and 30mm LN model detectors must be moved about 0 15 down to clear the stage Installing the adapter ring between ECD flange and baseplate will do this 1 Turn off the instrument power switch For ECD systems disconnect the instrument power cord This is required to remove all power from the chamber board socket 2 Remove the baseplate cover and tray support pads if present from the baseplate 1 Remove the tray drive assembly if present 1 Detector removal follow the instructions in the Technical Manual section 9 6 1 or 9 6 2 as appropriate 1 Apply a thin coat of vacuum grease on the new o ring provided and install it into the adapter o ring groove 1 Transfer the insulator from detector mounting flange to the top of the adapter ring and place them both on top of the detector mounting flange see the attached drawing SKT 8000 1 1 Align the holes in the adapter and insulator with the detector flange screw holes Temporarily install two set screws 8 32 x 4 provided into two opposite detector flange screw holes to hold the parts in place and align the adapter ring with the detector 1 Install the detector adapter assembly temporarily onto the chamber basep
218. signal is not being generated correctly due to Remedy Reference Check that the sample tray can be rotated one full rotation by hand with the power off Check connections at the chamber Figure 3 4 distribution board Motor is J3 sensor is J4 Verify with SAMPLE HOME LED on the 5919 0217 chamber control board With the power on SHD let the tray rotate As the flag pin passes through the sensor tray in position 1 the LED should turn on always off otherwise If bad see the following causes Spectrace Instruments QuanX Technical Manual Troubleshooting 10 31 Flag is not breaking the light Verify by inserting opaque paper in sensor beam located under the tray driver toward the rear If the SAMPLE HOME LED turns on only when paper is inserted the flag pin is missing or is too short Try pushing down on the tray driver Faulty optical home sensor To verify Plug the tray sensor connector J4 Figure 3 4 into the chamber distribution board J5 filter sensor position and rotate the tray If the FILTER HOME LED lights only when the flag is in the sensor then the tray sensor is good go on to next cause otherwise replace the sensor If the motor does not turn when the power is first turned on see the following causes Bad or missing tray drive The chamber board will not try to turn the 5919 0127 tray installed jumper in the motor tray unless a jumper is in J3 pins 5 to 6 in connector If TXCONFIG is n
219. sin einen dade 8 11 9 Component Replacement Spectrace Instruments QuanX Technical Manual 10 11 12 9 o Ku rte te NEE 9 1 9 2 Special Precautions su silana edet ate E Pede bee 9 2 9 3 Circuit Braderie Sets RR UR E HU p LER OR EE e Ch 9 3 94 Powet Supplies ertet epe edere i edt e ie epe ede dr eta 9 7 9 5 Sample Chamber Components essere eren enne nennen 9 12 9 6 Detector Assembies eet eer ege ii aca 9 14 9 7 Miscellaneous Items ated etd eet et EH et eed eet ce Leere 9 18 Troubleshooting 10 1 Introduction s det e te al E RR pudiera 10 1 10 2 Nominal Ranges For System Status Values eee 10 2 10 3 Hardware Error Messages sees eene nennen 10 3 10 4 Troubleshooting Charte EE heed ae tee 10 11 Optional Equipment 11 1 Introduction ie ee A ete LR e ends 11 1 11 2 Heliim El sh inane bereitet net ert ere fibvaoslsesceeseptteete sees 11 2 11 3 R Theta Sample Stage sese 11 4 11 4 Y Th ta Sample Stage ii edaria iere sei 11 5 11 5 XY sample EE 11 6 Drawings and Schematic Diagrams Spectrace Instruments QuanX Technical Manual 1 General Information Table of Contents T Introductio BEE 1 1 1 2 Scope of th Mammalia ee RE ep Ue ug e e pa a ee 1 2 1 3 Reference Doc ments ea Fer le GEHE OR e EU e e PR MEER pene REES 1 3 1 4 Service and S ppott EE 1 4 Spectrace Instruments QuanX Technical Manual 1 1 General Information 1 1 In
220. sition selected X ray tube anode current set to zero Fast discriminator requires adjustment ADC or chamber board requires a logic reset Output cable between the bias supply board and the pulse processor board is disconnected A board is not inserted correctly in the card cage Detector high voltage bias is off Hardware failure which requires on line diagnosis Check the system status screens for the following possible causes Troubleshooting Run a resolution test The noise pickup will also cause poor resolution If poor resolution is found correct it first and the low energy sensitivity problem will most likely be corrected See Resolution is poor Verify on the GENERAL STATUS screen The bias supply 1v should be greater than 0 95 If it is low replace the bias supply module Verify by substitution replace if required Verify by substitution replace if required Clean the window per procedure CAUTION READ THE PROCEDURE SERIOUS DAMAGE IS POSSIBLE Verify by substitution replace if required Remedy Raise the X ray kV setting or choose a different filter Install a sample Select a new mA value Adjust the fast discriminator control for 150 25 counts sec with the X rays off Exit the program turn the power off for 5 seconds and then back on restart the program Connect the coax cable Turn off the power Reseat the boards firmly Verify that the HV light on the bias s
221. ssumed No explicit warnings are given for personal safety or potential damage to the instrument For this information read the special precautions listed elsewhere in this manual For an explanation of the meaning of the error messages refer to the previous section Hardware Error Messages Some entries are dependent on the type of detector installed in the instrument LN or ECD Most of the ECD only related entries are followed by ECD Spectrace Instruments QuanX Technical Manual 10 12 Troubleshooting 10 4 2 Troubleshooting Chart Index A acq aborted coolers are off 10 18 acq abortedV det bias voltage off 10 19 acq aborted ecd thermal shutdown 10 18 acq aborted ion pump is off 10 14 acq aborted stabilizer lost zero peak 10 14 acq aborted zero dac at limit 10 14 acquisition aborted ecd coolers are off 10 24 acquisition failed to initiate 10 26 adc board does not communicate 10 14 adc failed to respond retry previous task or check hardware and reload program 10 14 ambient temperature inside the instrument is high 10 15 B background level is high 10 15 C chamber control board does not communicate 10 16 chamber failed to respond 10 16 check detector status 10 16 10 28 10 29 configuraton error options don t match txconfig setting 10 31 coolers are off 10 18 D dead time is high 10 16 dead time is low or erratic 10 18 dead time too high change parameters 10 16 detector hea
222. st following a written procedure e Semiannual radiation survey using an appropriate survey meter e Annual or semiannual certified calibration of the survey meter e Maintenance of a log book indicating the tests performed the date and the results e Formal employee training in basic radiation safety Record of the training provided should be maintained for state review Training may be required regularly or only once for each employee e Use of personal and or area dosimeter badges Some states will also perform random on site inspections which include review of your log book and your local safety practices and written procedures The radiation survey and interlock test procedures may be found in Section 7 of this manual Test and Adjustment Procedures 2 1 5 IEC 1010 1 Safety Requirements The QuanX system has been designed and verified by independent testing to meet the applicable requirements of IEC Standard 1010 1 Safety Requirements for Electrical Equipment for Measurement Control and Laboratory Use The following symbols are used to mark the QuanX according to IEC 1010 1 3xubar Description Publication Fuse IEC 417 No 5016 Protective conductor terminal JEC 417 No 5019 AN Caution risk of electric shock ISO 3864 No B 3 6 Spectrace Instruments QuanX Technical Manual Safety 2 4 Caution refer to ISO 3864 No B 3 1 accompanying documents Per IEC 1010 1 the power cord acts as a mains disconne
223. structions Test equipment Dosimeter ring or badge Survey meter Victoreen model 493 with model 489 35 probe Delrin scatter block sample 1 x1 lead sheet Radiation Survey Recording Form No 226 Test conditions Procedure 7 7 X ray Power Supply Control Board Adjustment must have been performed if there is any reason to believe that the board may not be functioning correctly An X ray beam collimator must not be installed in the filter wheel holder Optional The diagnostic diskette contents has been installed and the QUANX program has the active directory set as C SPECTRAC QTESTLN or C SPECTRAC QTESTECD for an LN or ECD system respectively Safety precautions Radiation hazard Test personnel must wear a dosimeter during the test Procedure 1 Fill out the survey form 1 Verify that the survey meter has been calibrated within the last year Use the test source supplied with the meter to verify that it is working correctly 1 Remove the sample tray from the chamber there will be no sample for the first part of this test 1 All the QuanX enclosure covers should be in place 1 Select RADIATION SURVEY from the procedure menu or set up an acquisition with the following conditions Tube voltage 50 kV Tube current 1 00 mA Filter No filter Livetime 0 sec Preset count 0 Max energy 20 keV Atmosphere Air Warmup 0 sec Spectrace Instruments QuanX Technical Manual 7 15 Test and Adjustment Procedures Press RU
224. struments QuanX Technical Manual DISCARD THIS PAGE Spectrace Instruments QuanX Technical Manual DISCARD THIS PAGE 10 Troubleshooting Table of Contents 10 1 Introducti n 24 23 bie d eee bee pee e de eed 10 1 10 2 Nominal Ranges For System Status Values esee eene 10 2 10 3 Hardwa re Error Messages eere ree teo 10 3 10 4 Troubleshooting Chart EE 10 11 10 4 1 Ihtrod ction o em Ge c eee een eel el eae eee 10 11 10 4 2 Troubleshooting Chart Index Spectrace Instruments QuanX Technical Manual Troubleshooting 10 1 10 1 Introduction This section presents information useful to the operator as well as to the service technician The section begins with a listing of the typical system status indicators produced by a properly functioning system This is followed by a description of system error messages These subsections are useful when attempting to determine whether the instrument is functioning correctly or not The latter portion of this section is dedicated to the location and resolution of failures Spectrace Instruments QuanX Technical Manual 10 2 Troubleshooting 10 2 Nominal Ranges For System Status Values Introduction The QuanX monitors an several system parameters These include actual voltage and temperature measurements pass fail sensor signals and X ray detector performance indicators The values of these parameters are shown on various screens called status pages The following table specif
225. supplies used to power the instrument These include two linear supplies which power the detector preamp and detector electronics and two switching supplies which provide power for the X rays and various machine functions The tray slides out for service access The X ray control board controls the voltage and current applied to the X ray tube It accepts digital commands from the chamber control board and executes them by setting the X ray high voltage power supply to the desired voltage output and adjusting power to and thus the temperature the X ray tube filament to obtain the desired tube current This board also is a junction point for many of the safety interlock circuit connections The ADC interface cable connects the ADC board located in the QuanX card cage to the ADC interface board located in the PC This cable carries digital spectral data as well as ADC control and status information The cable is a 50 conductor fully shielded ribbon cable with high density shielded connectors at each end Figure 3 3 shows a right side view of the QuanX with the enclosure cover partially cut away Each item identified with a callout is discussed below X RAY TUBE AND SHROUD Es E X S E SSS ASSES SSS x SS
226. support and monitoring The ion pump is powered by U6 under normal operating conditions The power leaves the board on J5 pin 4 relay K2 is energized and so has no affect When the instrument power cord is unplugged the backup battery power enters the board on J5 pin 3 goes through K2 and out J5 pin 4 to the ion pump power supply The voltage for the ion pump power supply is also a signal called IPP which is connected to comparator U1 to generate the ION PUMP ON signal which is read by the computer The ion pump power supply has a current monitor output which generates a voltage proportional to the ion pump current 1mV 14 A This voltage is amplified by US and then connected to J1 pin 8 for measurement by the chamber board ADC circuit and also is connected to comparators U3 and U1 to generate an alarm signal The ion pump current signal is also used in an auto defrost circuit Over a long period of time gas molecules will collect on the cold internal components of the ECD When the ECD is warmed up to room temperature the molecules become mobile and in severe cases can overload the ion pump The auto defrost cycle is initiated by turning off the coolers via the signal TURN OFF COOLERS J1 pin 11 low off This is a software controlled signal from the chamber control board It turns off the coolers via U3 pin 1 to U2 pin 1 If the ion pump exceeds 3001A U2 pin 13 goes low which turns the coolers back on the LM339 comparators have open coll
227. t high performance Energy Dispersive X ray Fluorescence EDXRF analyzer The instrument uses an X ray tube excitation source and a solid state detector to provide simultaneous spectroscopic analysis of elements ranging from sodium to uranium in atomic number and in concentrations ranging from a few parts per million to 100 percent Instrument control and data analysis are performed by a personal computer that is connected to the system For the purpose of introducing the reader to the QuanX this section begins with a tour of the instrument The name function and location of major components are described This information provides a basis for understanding the other sections of this manual The section concludes with detailed specifications of the unit Spectrace Instruments QuanX Technical Manual Product Description 3 2 3 2 A Tour Of The QuanX 3 2 1 Overall System Figure 3 1 PC Interface The system is composed of two parts the instrument and the Personal Computer The instrument contains the X ray generating elements sample chamber detector detector electronics microprocessor controller and associated power supplies The personal computer PC includes the ADC Interface board and other standard PC elements Figure 3 1 shows the connections between the QuanX spectrometer and the PC Spectral data are transmitted to the PC via the ADC Interface cable Instrument control is accomplished via the RS 232 serial conn
228. t is supplied with the capability to be remotely operated via modem This feature is extremely valuable when service or applications help is required A direct outside line is normally required for modem operation Spectrace Instruments QuanX Technical Manual 5 4 Installation 5 3 Special Precautions Beryllium windows The X ray tube and ECD detector both have beryllium windows which are extremely fragile and brittle Since beryllium metal is highly toxic do not touch or otherwise handle the foil DO NOT touch jar or subject the beryllium windows to mechanical or thermal shock or to corrosive substances Do not store the instrument in a corrosive or high humidity environment When installing replacing or working around the X ray tube and the detector assemblies proceed with great caution If analysis of samples emitting corrosive fumes is anticipated contact our applications department before performing the analysis Corrosive fumes can permanently damage the X ray detector assembly in a matter of minutes Refer to Section 2 Safety for more information Ion pump power ECD model only The ECD detector assembly must be maintained at a high vacuum to eliminate heat loss due to gas conduction and to prevent contamination of the detector crystal This vacuum is maintained by the continuous operation of an ion pump Power for this pump normally comes from the AC line or from the internal backup battery if the instrument is not plugged in
229. t sink temperature is high 10 18 detector high voltage bias is off 10 19 detector temperature is too high 10 19 E energy calibration fails to execute successfully 10 21 energy calibration is unstable long term peak shift 10 22 external cooler voltage is high 10 22 F failed to download file to adc 10 14 failed to initialize filters 10 23 fast discriminator cannot be adjusted properly 10 23 filters do not position correctly 10 23 H high ambient temp check system status 10 15 high voltage arcing 10 24 interlock circuit failure detected service required 10 25 ion pump current is high 10 25 Spectrace Instruments QuanX Technical Manual ion pump is off 10 14 L Troubleshooting low energy sensitivity is poor 10 26 N no spectrum is produced 10 26 P preamp reset rate is too R high with x rays off 10 28 repeatability of analysis results is poor 10 28 resolution is poor zero S width is high 10 29 sample tray failed to locate home 10 31 spectrum contains periodic errors 10 32 stabilizer lost zero peak 10 14 stray lines unwanted elements appear in the spectrum 10 32 system failed to calibrate hardware problem 10 21 10 22 X x ray stability is poor 10 32 x rays do not turn off 10 33 x rays not off hardware problem confirm signal failure 10 33 x rays not on hardwar x rays not on hardwar x rays not on hardwar e problem e problem interlock h
230. tage to 4 kV Close the lid lock sensing switch see Figure 7 5b by pushing on its lever The XRAY ON DS1 LED on the X ray power supply control board should turn off the X ray warning sign will stay on though Release the switch lever DS1 should turn back on Stop the acquisition 1 Open the chamber lid very slightly at a point where DS2 is on but the lid latch will not lock properly Start an acquisition The X rays should not turn on and the computer should display a chamber failed to lock message Close the lid 1 Unplug the X ray warning light DB9 connector from the rear panel Start an acquisition the X rays should not turn on LED DS1 should stay off and the computer should display a X ray warning light failure message Reconnect the connector Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 12 7 7 X ray Power Supply Control Board Adjustment Scope and purpose To complete the required board adjustments and check portions of it for proper operation This procedure may be used to verify the board adjustments or to check a new board after replacement Test equipment Digital voltmeter DMM 100 MHz oscilloscope Test conditions Fully functional X ray tube and power supply should be connected The tube must be mounted in the shielded sample chamber The main enclosure cover should be removed Procedure 1 Check that the 30 50 kV switch is set to the 50 kV position 1 Turn on the s
231. tate devices which utilize the Peltier effect to produce cooling Heat is pumped from one surface to another when a DC current is passed through the device Since this heat is transported by electrical charges there are no moving parts which can wear out or cause vibration The detector FET and a temperature sensor are mounted in the stack assembly which attaches to the cold side of the coolers Their hot side is attached to an external cooler and its hot side is connected to a heat sink outside the housing The detector s temperature is maintained at a constant level by varying the drive current to the external cooler The X ray detector FET and internal coolers are contained within a housing which is evacuated to a high vacuum in order to eliminate heat loss due to gas conduction and to prevent contamination of the detector crystal This assembly is shown in Figure 4 3 This vacuum is maintained by the continuous operation of an ion pump The pump contains a cathode made of titanium and an anode A 3 kV DC potential on the anode causes gas molecules inside the pump to ionize These positively charged ions are accelerated into the cathode where their impact causes titanium to sputter onto the walls of the pump Titanium is very reactive and chemically unites with active gases to form compounds which adhere to the walls Noble gases which are non reactive are pumped by burial under the sputtered titanium The gas ionization process is enhanced by mea
232. ted with the DOS diagnostic programs normally supplied with it Instructions for these programs are contained in the computer s operation manual Spectrace Instruments QuanX Technical Manual Diagnostic Software 8 2 8 2 Diagnostic Disk Installation Scope and purpose The diagnostic diskette supplied with this manual contains files with preset parameters for various system tests The disk contents should be installed on the fixed disk and the master diskette kept as a backup This is especially important for the test procedure files since they can accidentally be altered during testing Required equipment 8150 0129 Diagnostic diskette Procedure The disk contents will be copied to two new directories called CASPECTRACIQTESTEN and CASPECTRACIOTESTECD 1 Exit the QUANX program if required to return to the DOS prompt 1 Insert the diagnostic diskette in drive A 1 Start the installation program by typing C gt A INSTALL 1 When the contents have been copied remove the diskette and store it in a safe place Spectrace Instruments QuanX Technical Manual 8 3 Diagnostic Software 8 3 ECHOA PROGRAM The ECHOA program allows the service technician to exercise various instrument hardware functions by sending simple ASCII text commands to the chamber control board This capability is useful for troubleshooting specific hardware malfunctions The ECHOA program is supplied on the QUANX program diskette and the diagnostic diskette After
233. terface using ASCII character codes The board has a predefined instruction set based on the version of EPROM installed Different EPROMS are required for option support such as the R Theta sample stage A typical control communication sequence is as follows The PC will issue a command for example to move the filter wheel the board will echo back the same command characters as confirmation of receipt execute the command and send a carriage return CR when the execution is complete filter is in position The PC may also query the board for several machine status conditions The echo CR protocol is always used regardless of the type of communication A program called ECHOA is provided to allow a technician to communicate directly with the chamber board for troubleshooting purposes See Section 8 Diagnostic Software for a description of the ECHOA program and a complete instruction set listing Voltage measurement An analog to digital converter ADC circuit is included to measure all system power supply and critical signal voltages for troubleshooting purposes U5 and supporting components form the ADC circuit Multiplexers U6 8 act as selectors to choose which voltage is to be measured U5 can only measure one at a time The selection is made via the VSO VS2 and VCS0 VCS2 chip select signals issued by the microcontroller U17 via 8255 U14 and decoded by U13B Most of the voltages must be conditioned before presentation to the ADC becaus
234. tery connector is a 2 pin connector used to connect an external 12V source to power the ECD ion pump during shipping or other extended power outages The external battery works in conjunction with the internal backup battery to extend the time the instrument may be disconnected from an AC power source The external battery is not recharged when the instrument is plugged into an AC power source The connector mates to a Molex 09 50 3021 or equivalent connector This connector is not used if the instrument has a LN detector The motherboard access panel may be removed to gain access to the system cabling The motherboard is the junction point for most of the system power and signal cables The vacuum port is the connection port for the vacuum pump hose It is a 5 8 inch barb hose fitting Vacuum is used to analyze low atomic number elements because their low energy X rays would be absorbed by the air in the chamber Liquid samples may not be placed under vacuum The helium port optional is the connection point for the helium gas used to flush the sample chamber when analyzing low atomic number liquid samples The input pressure must be in the range of 15 to 65 psi The fitting is a inch hose barb Spectrace Instruments QuanX Technical Manual 3 11 Product Description The vacuum pump power outlet is a standard NEMA 5 15R receptacle The vacuum pump power cord is plugged into this outlet The vacuum pump must be rated for the AC line voltage conne
235. that powers the high voltage power supply actually passed through all the interlock switches This fail safe design insures that even if the logic or control circuit fails on any entry into a potentially hazardous area by an operator or technician will automatically stop the generation of X rays Self monitoring Diagnostics Three mechanisms are employed to automatically detect interlock or control failures and alert the system operator One is a system level check performed by the QUANX program and the others are hardware checks performed locally in the QuanX itself To verify that the control circuits are functioning correctly the INTEROUT voltage is monitored by the analysis program running on the personal computer Every time an acquisition is completed and the X rays are turned off K1 and K3 de energized the computer reads a chamber board signal named CONFIRM This logic signal is generated by the INTEROUT voltage output of relay K3 which should be zero when the X rays are off If the computer determines that the X rays are on when they should be off an error message is displayed on the computer display and continued operation of the system is not allowed The CONFIRM signal is also checked every time an acquisition is started and the X rays are turned on This is done primarily to alert the operator if the X rays fail to turn on for some reason but also serves to test the function of the CONFIRM signal circuitry so that a fail in the
236. the WRT line latches the output of U7 into the appropriate DAC U8 is the voltage DAC and U10 is the current DAC Current Control In an X ray tube electrons flow from the filament to the target where they produce X rays upon impact The magnitude of the current depends on the temperature of the filament An AC current from transformer T1 heats the filament A pulse width regulator U1 controls the AC current by varying the width of the pulses used to drive the transformer The regulator has a feedback path designed such that U1 heats the filament to cause a current flow to the tube target anode equal to a reference current established by control DAC U10 This reference current is produced by the circuit consisting of Q3 R26 U10 and U11 When the high voltage supply is off relay K1 switches the feedback to a second circuit whose output is proportional the pulse width of the AC drive This causes U1 to supply a small amount of AC current to the tube filament to keep it warm Voltage Control The output voltage of the high voltage power supply is controlled by varying a voltage to its control input There is a linear relationship between these two voltages The control voltage is derived from a reference voltage provided by the high voltage supply This reference voltage corresponds to the supply s maximum output voltage For example if a reference voltage of 10V is provided by the power supply then applying 10V to the supply s control input will
237. the dewar The cold finger and crystal are also under the same high vacuum The beryllium window acts as an X ray transparent vacuum tight seal Instruments equipped with an ECD do not contain this assembly and are discussed below Spectrace Instruments QuanX Technical Manual Product Description 3 8 The ADC interface cable connects the ADC board located in the card cage to the ADC interface board located in the PC This cable carries spectral data from the QuanX to the PC The PC also sends commands to and receives status from the ADC board over this cable The ADC analog to digital converter board converts the pulse processor output signal from analog to digital data in other words from a DC voltage proportional to X ray energy to a channel number proportional to energy It transmits the result to the ADC interface board in the PC Figure 3 5 shows a top view of an ECD QuanX with the left lid and ECD support tray s protective cover removed Each item identified with a callout is part of the ECD support tray except the ECD itself and is discussed below The ECD control board performs various ECD support functions including temperature regulation and monitoring Protection circuits include alarms for high ion pump current high heat sink temperature and high cooler drive voltage Four LEDs on the board indicate the status of these alarms each light is on under normal non alarm conditions The cooler on off switch is located on this boar
238. the external cooler voltage is at 7 4 volts or higher which is about 9096 of its maximum value When this occurs an operator warning message is displayed U3 generates the signal by comparing the voltage X2 with a reference voltage The heat sink temperature is monitored using a NTC thermistor mounted to it The thermistor and R25 form a voltage divider circuit U5 buffers the output which connects to two points First the U5 pin 7 voltage leaves the board on J1 pin 2 to be measured by the chamber board ADC Second U3 compares the voltage to a reference If the U5 pin 7 voltage falls below the reference high temperature then U3 pin 2 goes high which turns off the coolers via U2 and Q1 to prevent the heat sink temperature from increasing further Also the signal HEAT SINK OK will switch states This signal will go high when the heat sink exceeds 55 C and an operator warning message will be displayed High heat sink temperature is the only condition that will automatically turn off the ECD coolers Test points Most of the important voltages are present on TP1 for measurement with a voltmeter These voltages are also connected to the chamber control board via J1 for measurement and display on the PC monitor Some of the voltages require conversion to provide meaningful information these are described below e TP1 2 Heat sink temperature C 90 5 35 8V 5 0V where V is in volts A typical operating temperature is approximately 33 C or
239. the flow meter in the compressed air line Connect the compressed air to the rear panel HELIUM input nipple 1 Verify that the flow meter reads zero flow 1 Start an acquisition with HELIUM atmosphere 0 seconds LIVETIME and any other conditions 1 Verify that the flow meter reads 7 0 1 0 SCFH during the 2 minute purge 1 Verify that the flow meter reads 1 5 0 5 SCFH during the analysis 1 Reduce the air pressure while the analysis is running The computer should display a helium Low pressure warning message when the pressure is in the 10 15 psi range 1 Reset the pressure to 80 psi and restart the acquisition Wait until the purge stops and the acquisition begins Press EXIT to stop the acquisition and verify that the flow rate is zero Alternate procedure If a flow gauge is not available a simple test of the basic operation may still be performed 1 Set the compressed air source to 80 psi 1 Connect the compressed air to the rear panel HELIUM input nipple 1 Start the ECHOA program using the proper argument for QuanX communications by typing C gt ECHOA Q 1 Open the sample chamber lid 1 Turn on the helium low flow valve by typing CDO CX J l Listen carefully for the sound of air flowing inside the sample chamber Spectrace Instruments QuanX Technical Manual 7 49 Test and Adjustment Procedures 1 Turn off the low flow valve by typing CDF J CX J The air flow should stop 1 Turn on the helium high flow val
240. the keyboard Many procedures give two values for the acquisition parameters The first is for an instrument equipped with a liquid nitrogen cooled detector This is followed by a value in parentheses which is for an instrument equipped with an electrically cooled detector If only one value is given then it is applicable to both configurations Preset parameters for several tests are stored in files on a diagnostic diskette P N 8150 0129 supplied with this manual Use of the disk is helpful but not required All test parameters and setup information are detailed in each test procedure The disk contents may be installed using the INSTALL program on the disk and as described in Section 8 Diagnostic Software The files will be located in two directories called C SPECTRAC QTESTLN and CASPECTRACIQTESTECD The test parameters are slightly different for LN and ECD systems Start the QUANX program from the appropriate directory or use the CDIR function within QUANX Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 2 7 2 Fast Discriminator Adjustment Scope and purpose To adjust the fast discriminator threshold of the pulse processor so that the processor rejects background noise but does not cut off the low energy portion of the spectrum This threshold should be checked weekly and adjusted whenever the ADC board the pulse processor board or the detector has been changed Test conditions Complete fully fun
241. the left lid and chamber lid removed The metal cover plate inside the sample chamber is also removed to expose various components Each item identified with a callout is discussed below Spectrace Instruments QuanX Technical Manual Product Description 3 6 ENCLOSURE FAN DETECTOR PREAMP CABLE ARS Y SAMP TRAY DRIVI MBLY OPTIONAL CHAMBER CONTROL BOARD N PULSE PRO CHAMBER DISTRIBUTION BOARD d VENTED SCREW DETECTOR BIAS SUPPLY ADC BOARD ADC INTERFACE CABLE JETECTOR LN DETECTOR ASSEMBLY Figure 3 4 Top view LN model The detector bias supply provides the high voltage 300 600 VDC required to operate the Si Li detector crystal It is also the connection point for the other detector preamplifier signals and power supplies The chamber control board is a self contained microprocessor based controller It accepts commands from and sends status to the PC via the RS 232 serial communications link It controls all machine functions such as rotating the sample tray and filter wheel turning on and off the X rays monitoring the safety interlock circuit turning on and off the vacuum pump etc The enclosure fan provides cooling air for the entire en
242. tialization process Theta stage failure sets an error bit and initialization continues e Initialize the R Theta or X Theta rotation axis if installed Locates the home flag via the optical sensor Failure to find home sets an error bit and initialization continues Spectrace Instruments QuanX Technical Manual 4 13 Theory of Operation The initialization using the optical sensor involves locating both edges of the home flag and then centering the flag in the sensor This can be observed as the device for example the sample tray rotates one direction reverses direction as required to locate the flag edges and stops If an initialization error bit was set a warning message will be displayed on the computer when the QUANX program is started Stepping motor control The board can control four stepping motors One to turn the filter wheel another for the sample tray or Theta stage linear motion the third for the Theta stage rotation axis and the fourth for the sample spinner drive All the motors are 2 phase uni polar configuration The sample tray drive and Theta stage each short a signal line oTRAY IN THETA IN to ground when it is plugged in This informs the microcontroller of its existence The circuits used to drive all but the spinner motor are identical The motor windings are driven by MOSFET transistors with signal names FD1 FD4 filter SD1 SD4 sample tray TD1 TD4 theta spinner The inverters serve to buffer the si
243. tion 0127 amp 0128 ROM R Theta linear position 0129 ROM X Theta linear position future ROM Chamber lid lock sense actual hardware check Diagnostic Software Usage Respons e AJO AJF AKO AKF ALO ALF XXXXy AXX ANO APO APF AQO AQF ARO ARF ARW AXX ASF AXXX AXXX ASF ATO ATF Response Description Light is ON Light is OFF X ray power is actually ON X ray power is actually OFF Coolers are set ON Coolers are set OFF Rom Id 8140 xxxx y revision letter A to Z xx Number of tray positions supported No sample tray drive installed X rays are set ON X rays are set OFF Current is OK Current is HIGH Vent is OPEN chamber open to air Vent is CLOSED Vent is OPEN but chamber is still under vacuum WAITING for air Sample tray is in position xx 1 Sample tray drive option is not installed Linear position is xxx 0 00694 inches forward of home Option is not offered at the time of this manual publication Linear motor not connected or linear axis failed to locate home position Lid 1s locked Lid 1s not locked Spectrace Instruments QuanX Technical Manual Comman d query QU QV00 QVOI QV02 QV03 QV04 QVOS QV06 QVO7 QVOS QV09 QV10 Qv11 Qv12 Name Helium flush status Read ECD base temperature Read ECD board 12V regulator voltage Read ECD internal cooler voltage Read ECD heat s
244. to be entered should be placed at the end of the file Spectrace Instruments QuanX Technical Manual 5 10 Installation Sample AUTOEXEC BAT file PATH C C DOS C SPECTRAC CADOSISMARTDRV C SPECTRACE TSRFONT COM INIT_VDIS PROMPT P G XRAYOFF 4 Notes 1 Specifies a search path for DOS to locate files The path may be increased by adding additional sub directories but must contain at least the sub directories shown 1 Establishes a disk cache in upper memory Improves system performance by reducing fixed disk access times 1 Initializes the VDI controller 1 Configures the DOS prompt to display the current path This may be modified as desired 1 Executes a Spectrace Instruments program which turns off the X rays This is included in case the computer was reset during an acquisition 1 This line should only be included if needed It corrects a graphics display problem associated with certain brands of video board The problem appears as garbled function key icons and peak labels The preceding examples detail the minimum configuration required to operate the analysis software DOS offers a number of optional features designed to optimize the speed and flexibility of the computer Refer to the DOS documentation for details relevant to your particular computer configuration 5 5 3 ADC Interface Board Installation Following are instructions for installing the Spectrace ADC interface board for use in PCs with a
245. to reach operating temperature Spectrace Instruments QuanX Technical Manual 10 19 5919 0207 heat sink ok 5919 0207 J4 pins 6 amp 7 Reference Figure 3 4 Figure 3 5 Procedure 7 24 Figure 3 4 Procedure 7 4 1 Procedure 9 3 3 Contact factory Procedure 9 3 3 Reference Figure 3 5 10 20 The detector heat sink temperature is too high Both the detector temperature and the base temperature are high because Poor vacuum in the detector housing External cooler voltage is low because Faulty cooler power supply Faulty ECD control board Faulty base temperature sensor or bad connection to it Open circuit in the external cooler power path Det support screen may still read normal The detector temperature is high but the base temperature is normal because Internal cooler current is low Open circuit in the internal cooler power path Internal cooler voltage 10 V Troubleshooting Verify on the ECD STATUS screen heat sink should be less than 40 C If it is high see Detector heat sink temperature is high Verify on the ECD STATUS screen the base should be less than 21 C If high see following causes Check the ion pump current on the ECD STATUS screen If it is above 20 or is O see Jon pump current is high Verify on the ECD STATUS screen When the base temp is high the ext cooler voltage should be at max greater than 7 5 V The ext
246. top switches which interrupt the motor power if the stage travels beyond its normal operating range A special chamber board ROM chip P N 8140 0130 is required to operate the Y Theta stage Also the chamber board switches SW1 and SW2 must be set to the THETA position See Figure 11 3 for an illustration of the Y Theta stage Technical drawings are included in Section 12 Drawings and Schematic Diagrams e CN G NO ZN ez E O My M e eS Pd N A ET ROTATION MOTOR TTT d e Di Q Ar d A Se e E WAFER ec YN N DO i INSERT RING Ba X y N N f A V eh 5 D 2 1 J X N 7 CALIBRATION TRAY NW c L V L N Y 3 e N J Ql lt AA i J Figure 11 3 Y Theta stage top view Spectrace Instruments QuanX Technical Manual Optional Equipment 11 6 11 5 XY Sample Stage 11 5 1 Description The XY stage is used to analyze dried water samples Sizes accommodated are either 2mXa sample frames two 5cm square samples or two 32mm round disks Sample positioning is fully automated and is under the control of the analysis program XYQUANX Positioning is accomplished by linear front to rear and left to right translations S
247. troduction This service manual describes the Spectrace Instruments QuanX analyzer The manual is designed to acquaint the service technician with the instrument its hardware and software characteristics its installation and the service procedures that can be performed on site This manual is written for service technicians who have general experience with electronic circuits and standard bench instruments No expertise with X ray or elemental analysis techniques is assumed the references listed in this section should enable the interested reader to get acquainted with these topics This manual does assume that anyone working with the QuanX has become somewhat familiar with its operation as described in the Operator s manual The following conventions are used in this manual QuanX refers to the hardware or complete system QUANX all caps refers to the DOS software used to run the system ECD means Electrically Cooled Detector and sometimes refers to QuanX systems equipped with the ECD LN means Liquid Nitrogen but in this manual also refers to the LN cooled detector and QuanX systems equipped with the LN detector See the Introduction to the Safety Chapter for additional conventions regarding Warnings Cautions and Notes Spectrace Instruments QuanX Technical Manual General Information 1 2 1 2 Scope of the Manual To achieve its stated goals the manual is organized as follows Section 1 General Information This secti
248. ttom of each side and sliding it directly forward Remove the X ray high voltage power supply as described in Procedure 9 4 1 Disconnect the wires from the front of the supply Note their location first Remove the screw that secures the front of the power supply tray to the enclosure Disconnect the two white in line connectors J5 amp J6 located on left side of the power supply tray This allows the tray to slide forward farther Flip up the radiation shield Slide the tray forward Free cables as required to allow about 1 3 of the tray to protrude Remove the green yellow wire safety ground wire from the supply chassis Rotate the tray 90 degrees clockwise Remove the screws securing the power supply to the tray Remove the AC supply wires from the terminal block on the rear end of the supply Note their location first Install the replacement supply by executing the previous steps in reverse order Do not install the enclosure cover Check or adjust the supply outputs per Procedure 7 4 Power Supply Test and Adjustment Install the enclosure cover 9 4 4 PS3 12V Linear See Figure 7 3 for the location of this supply Turn off the instrument power Disconnect the instrument power cord Remove the four rear panel screws which hold the enclosure cover in place Remove the enclosure cover by grasping it on the bottom of each side and sliding it directly forward Spectrace Instruments QuanX Technical Manual 9 9 Component Re
249. uanX and the OEM equipment built into it present potential hazards specific to their modes of operation Spectrace Instruments provides information about its products and the potential hazards associated with the use and care of these products The instructions and information presented in this manual are intended to help the service technician develop safe habits for working on the QuanX WARNINGS CAUTIONS and NOTES are an integral part of the instructions and in accordance with federal UL and industry standards are used as follows WARNINGS indicate that failure to follow instructions or precautions can lead to injury or death CAUTIONS indicate that failure to follow instructions or precautions can lead to damage to equipment NOTES convey information that can help the user operator or service technician get optimum performance from the equipment The use of NOTES implies no hazard to users or equipment Spectrace Instruments makes no representation that the readers of this manual are qualified or that the act of reading this manual renders them qualified to install troubleshoot maintain or repair the QuanX system Service technicians must be thoroughly familiar with and understand the safety procedures know how to recognize hazardous or potentially hazardous conditions and know how to take adequate precautions to protect themselves and others from possible injury Address questions and comments regarding safety to Spectrace
250. ube anode current Read ambient temperature Chamber lid closed sense RTheta rotation position Interlock interrupt status Diagnostic Software Usage Respons e AXXXX AXXXX AXXXX AXXXX AXXXX AXXXX AXXXX AXXXX Ayyyy AXXXX AXXXX AWO AWF AXXX AYF AZO AZF Response Description V xxxx 1000 V xxxx 100 V z xxxx 10 V z xxxx 100 V z xxxx 100 V xxxx 10 V xxxx 10 Stack temperature K 0 2784 xxxx yyyy 14 65 mA xxxx 100 500 Temperature C 92 5 0 9982 XXXX Chamber lid is CLOSED Chamber lid is OPEN Rotation position is xxx degrees from home Rotation motor is not installed or rotation axis failed to locate home position Interrupt ENABLED Interrupt DISABLED Spectrace Instruments QuanX Technical Manual Diagnostic Software 8 10 8 3 4 Error or Other Messages From the Chamber Board MESSAG DESCRIPTION E HI Does not understand the input command RST Indicates that a board reset has occurred Zl Input command must start with letter C or Q MAX Too many characters in the input command or the sample filter position or tube voltage current is too high END ADC Conversion Complete signal never detected when attempting to read a voltage OVR Answer received from reading a voltage is over range INT Interlock interrupt has occurred ERO Chamber vent valve is open ERF Chamber vent valve is closed EHO Helium flush is on
251. ue paper in sensor beam If the FILTER HOME LED turns on only when paper is inserted the flag pin is missing or is too short Faulty optical home sensor To verify Plug the filter sensor connector J5 Figure 3 4 into the chamber distribution board J4 tray sensor position and rotate the wheel by hand If the SAMPLE HOME LED lights only when the flag is in the sensor then the filter sensor is good go on to next cause otherwise replace the sensor If the motor does not turn when the power is first turned on see the following causes Spectrace Instruments QuanX Technical Manual 10 24 Troubleshooting Faulty chamber control board or Verify by substitution or for systems Procedure stepper motor equipped with the sample spinner or theta 9 3 1 stage option second feedthru cable installed Procedure in the chamber distribution board J2 see the 9 5 1 diagnosis method below Plug the filter motor connector J6 into the chamber distribution board J7 spinner drive position set chamber board SW1 and SW2 to the SPINNER position run ECHOA Q type CBO J CX J If the motor turns smoothly the chamber control board is bad If the motor doesn t turn the motor or a connection is bad HIGH VOLTAGE ARCING X RAYS NOT ON HARDWARE PROBLEM CONFIRM SIGNAL FAILURE X RAYS NOT ON HARDWARE PROBLEM WARNING LIGHT IS OFF ACQUISITION ABORTED ECD COOLERS ARE OFF Cause Remedy Reference Note Arcing can cause a variety of Verify that
252. upply is off then see Detector high voltage bias is off Set the program to SERVICE MODE via the TXCONFIG program and continue to the next cause Spectrace Instruments QuanX Technical Manual Procedure 7 11 Procedure 9 3 3 Procedure 9 3 2 Procedure 9 3 4 Procedure 7 25 Procedure 9 6 Reference Procedure 7 2 Figure 3 4 Section 8 4 Service mode Faulty power supply or adjustment required Preamp reset rate is above 1 reset per 2 seconds LN or 10 resets per second ECD X rays off Detector temperature is above 190 K ECD Ion pump current is above 20 HA ECD No X rays are being generated No X rays being generated pa reset rate doesn t change due to Faulty voltage current control board Faulty X ray high voltage power supply Faulty X ray tube X rays are being generated pa reset rate changes but no spectrum due to Faulty pulse processor module Faulty ADC board Faulty power supply Faulty ADC interface board Troubleshooting If a voltage is out of range adjust per procedure must use procedure values or replace the power supply See Preamp reset rate is too high See Detector temperature is too high See Jon pump current is high Turn on X rays if X rays are being generated the preamp reset rate will increase substantially See the following causes Verify with all entries except HV monitor in X rays on portion of the G
253. used They may be skipped if the sample has already been characterized 1 Pour some manganese powder in the sample cup enough to completely cover the bottom of the cup with a thick layer Place the sample cup in tray position 1 1 Select LIVETIME TEST from the procedure menu and press SETUP or set up the following conditions Overall setup ACQUISITION PARAMETERS ANALYSIS TECHNIQUE Tube voltage 20kV Method No analysis Tube current 0 14 mA 0 28 ECD Mode Run unknowns Filter used Pd medium Std file 400 Livetime 100 sec Preset count Ok Max energy 10keV Atmosphere Air Warmup 10sec SPECTRUM PROCESSING SAVE ON DISK Ref file no 400 Spectrum Elements of int Cu Intensities File number Results Ext program Spectrace Instruments QuanX Technical Manual 7 35 Test and Adjustment Procedures Spectrum processing setup SPECTRUM PROCESSING l CU GROSS ROI 7400 9400 EV Count rate range setup AMP COUNT RATE MEDIUM 3 Highlight ACQUISITION PARAMETERS and press RUN Enter 1 for the number of unknowns 3 The dead time should be 48 to 55 If not press ACQU MENU amp ACQU PARM and adjust the tube current Press EXIT to stop the acquisition 3 Pour the manganese out of the sample cup and into an empty container Return the sample cup to tray position 1 3 With the tube current set to the value determined in step 4 highlight ACQUISITION PARAMETERS and press RUN Enter 1 for the number
254. ustomer service representative for more information Spare Parts Several spare parts kits have been carefully selected as a means to provide very high on line time On site spare parts have proven a valuable tool in conjunction with the remote diagnostic troubleshooting capabilities to reduce down time to a matter of hours Various proposals have been designed to suit the needs and budget of the customer Contact your sales representative for a list and price quote Customer Involvement During the warranty period the user may be requested to perform simple tasks to assist the technician in localizing the problem This may include voltage measurements board module swaps or running special software routines Complex technical skill is not expected After the warranty period the degree of involvement is the user s choice Training From time to time Spectrace Instruments offers on site and in factory operational training for users Spectrace User School On site hardware maintenance training is also available Equipment Exchange All subassemblies are available for instant exchange Spectrace Instruments normally responds within one working day of the initial request Return Authorization Any time a part is to be shipped back to the factory a RETURN AUTHORIZATION number must be issued and included with the part Contact a customer service representative for the authorization number Spectrace Instruments QuanX Technical Manual
255. valve and the two helium valves are switched on and off by MOSFET transistors Q18 Q7 Q16 and Q6 respectively which provide a ground path for the Spectrace Instruments QuanX Technical Manual 4 15 Theory of Operation device solenoid the other end of the solenoid is connected to a power supply The vacuum pump is controlled by Q5 which drives a solid state relay located in the AC distribution box Interlocks The overall system interlock circuit is described in Section 4 4 Safety Interlock Circuit This discussion will focus on the chamber board circuits only There are two microswitches on the sample chamber lid latch assembly one is actuated when the lid is closed and the other senses the motion of the locking solenoid shaft When the lid is closed and locked U22A and D are both low LID CLOSED amp LID LOCKED which generate a high LID OK This energizes relay K3 via Q3 The lid closed switch and K3 form an independent redundant chamber lid interlock circuit which is not the primary means of protection and control To explain the primary interlock and control circuits a typical X ray turn on sequence is described When all the interlock switches are closed 24V will be present at J1 7 referred to as INTERIN This signal is buffered and level tested by comparator U9D which generates a signal called INTERLOCK if INTERIN is at 24V and enables operation of flip flop U20 When an X RAY ON command is received U20 pin 6 goe
256. ve by typing CHO J CX JH 1 Listen for the air flow sound again This time is should be significantly louder than before The high flow rate should be about three times the low 1 Turn off the high flow valve by typing CHF CX J The air flow should stop 1 Turn on the helium low flow valve again by typing CDO J CX J 1 Check the pressure switch state by typing QU J The response should be AUL low flow valve on Start reducing the air pressure while typing QU J At a pressure between 10 15 psi the response should change to AUX low pressure Test complete Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 50 7 24 Detector Temperature Measurement ECD Scope and purpose To measure the temperature of the X ray sensor located inside the detector housing It is intended for those occasions when viewing the readout on the ECD STAT screen of the QUANX program is inappropriate This procedure only applies to systems equipped with the optional electrically cooled detector Test conditions Allow approximately two hours after turning on the coolers for the detector to reach operating temperature Test equipment DMM Procedure 1 Turn off the power switch Wait two minutes for the bias voltage to decay then disconnect the preamp cable from the bias supply 1 Measure the sensor resistance between pins 10 and 4 of the preamp cable using a DMM The resistance should be 760 ohms or lower for the detector t
257. wer Supply Control Board Adjustment should have been completed if the board s condition is unknown or suspect Procedure In this test the X ray tube current and anode voltage are varied and changes in some system parameters are observed The tube s X ray output intensity is directly proportional to the current Therefore an increase in the tube current will increase both the system count rate and dead time In this test we will observe the dead time as the current is varied The tube s output intensity is a nonlinear function of the anode voltage therefore the programming voltage for the high voltage supply is monitored when the anode voltage is varied 1 Place the copper sample in tray position 1 1 Highlight VOLTAGE AND CURRENT STEPS from the procedure menu and press SETUP or set up the following conditions Tube voltage 26 kV 30 ECD Tube current 0 10 mA Filter Pd thick Livetime 0 sec Preset count 0 Max energy 20 keV Atmosphere Air Warmup 0 sec Press SYS STAT COUNT RATE and select Medium count rate range Press EXIT 1 Highlight ACQUISITION PARAMETERS and press RUN Answer 1 for the number of unknowns to run 1 Press ACQU MENU then ACQU PARM to access the acquisition parameters menu If necessary adjust the tube voltage to get approximately 50 96 dead time Observe and record the dead time Reduce the current to 08 mA The dead time should decrease to approximately 43 percent Continue reducing the current in 0
258. with one screw 1 Connect all the motherboard connectors the ECD control board J4 connector the ECD cooler power supply J1 connector and ground wire and the heat sink hose 1 Connect the ion pump cable to the ECD ion pump Connect the ion pump power supply J1 connector Verify that the red LED turns on 1 Tap firmly a few times on the ECD ion pump with a screwdriver handle or similar object to ensure that the ion pump has started See Figure 4 3 for the location of the ion pump 1 Plug the instrument power cord in Turn on the cooler switch located on the ECD control board All the board LEDs should be on except the EXT COOL OK and it should turn on within ten minutes 1 Replace the remaining components 1 After two hours turn on the instrument power Using the ECD STAT screen verify that the detector temperature is within the normal range 1 Perform the following procedures a 7 2 Fast Discriminator Adjustment b 7 9 Initial Energy Calibration c 7 3 Energy Calibration d 7 11 Resolution e System standardization is required before beginning quantitative analysis Spectrace Instruments QuanX Technical Manual Component Replacement 9 18 9 7 Miscellaneous Items Replacement of various parts and subassemblies is detailed below 9 7 1 X ray Tube 1 1 Turn off the instrument power Remove the four rear panel screws which hold the enclosure cover in place Remove the enclosure cover by grasping it on
259. y detector assembly X RAY STABILITY IS POOR Cause After running the Stability test the total and peak RSD values are both poor due to an unstable tube output caused by one of the following Faulty X ray high voltage power supply Faulty X ray control board Faulty X ray tube After running the Resolution test the total RSD is good but the peak RSD is poor due peak shift or unstable resolution caused by one of the following Faulty pulse processor board Faulty ADC board Faulty power supply Unstable resolution Troubleshooting Perform a test with the single sample tray installed Run a test with the thin copper filter This filter will block any stray lines from the tube Clean the window per procedure CAUTION READ THE PROCEDURE SERIOUS DAMAGE IS POSSIBLE Verify by substitution replace if required Remedy Verification by substitution is best Alternative is to set the program to monitor the high voltage control and H V monitor on the GENERAL STATUS screen Print or save to a file over a many hour period If the analysis instability coincides with instability in the monitor but not the control signal the supply is the most likely cause Same remedy as above except set the program to monitor only the high voltage control and anode current Verify by substitution replace if required Verify by substitution replace if required Verify by substitution replace if require
260. ystem power Use a DMM to measure the voltage at TP6 TP2 is gnd it should be 15 0 75V 1 Observe the waveform on TP4 using an oscilloscope It should look like Figure 7 7 40 uS Ti lt 50 uS and 2uS T x 10 0S Figure 7 7 TP4 Waveform Measure the voltage at TP1 adjust R2 for 2 210V Measure the voltage at TP3 adjust R1 for 2 210V Check that the hinged radiation shield located at the front of the instrument is in its lowered position 4 Bypass interlocks as required and turn on the X rays using the QUANX in SERVICE MODE or ECHOA program Set the tube voltage to 25 kV and current to 0 02 mA ECHOA commands CCH25 CCI01 CTO CX CPO Cx 4 Measure the voltage at TP7 adjust to 5 00V using R33 Spectrace Instruments QuanX Technical Manual 7 13 Test and Adjustment Procedures 4 Set the tube voltage to 4 kV and current to 1 98 mA CCH04 J CCI99 CX note board doubles ECHOA current values Measure the voltage at U11 pin 2 it should be 1 72 0 06V Turn off the X rays Spectrace Instruments QuanX Technical Manual Test and Adjustment Procedures 7 14 7 8 Radiation Survey Scope and purpose To measure the radiation leakage outside the instrument at full power worst case conditions This is a safety related procedure This procedure is written for a particular model of survey meter If your meter is a different model disregard the particular references and follow your meter manufacture s operating in

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