Home

Agilent 8453 UV-visible Spectroscopy System Service Manual

1. Photometric accuracy lt 0 01 AU Potassium dichromate in 0 01 N H2SO4 at 235 257 313 350 nm blank scan on 0 01 N H2SO4 0 5 s integration time EP method 13 Specifications Performance Specifications Photometric noise lt 0 0002 AU rms Sixty consecutive scans on air with 0 5 s integration time at 0 AU 500 nm 11 point moving average using equation Noise rms SQRT SUM X x 2 n where x are measured values X is a 11 point moving average n is the number of points Photometric stability lt 0 001 AU h Scan on air at 0 AU 340 nm after 1 hour warm up measured over 1 hour every 60 s integration time 5 s difference between maximum and minimum values are compared to specification at constant ambient temperature Baseline flatness lt 0 001 AU rms Scan on air at 0 AU 340 nm 0 5 s integration time Typical scan time 1 5 s Full range Shortest scan time 0 1 s Full range Time until next scan 0 1 s Full range 0 1 s scan at least 150 consecutive scans EP stands for European Pharmacopoeia Apparent absorbance is strongly affected by dissolved oxygen According to ASTM bubble pure nitrogen through liquid for several minutes immediately before use Use only recently distilled water not demineralized water Table 2 Performance Specifications continued Type Specification Comments 14 Specifications Source of Standards Source of Standards Wavelength Accuracy The NIST 2034 Holmium Oxide s
2. Spectrophotometer lamp supply SLS board may be defective Exchange SLS board Main power supply MPS may be defective Exchange MPS Spectrograph electronics may be defective Exchange the optical unit 85 Diagnostics and Troubleshooting General Troubleshooting Hints Measurement Results Indicate Excessive Noise in Part of the Spectrum The selftest only Agilent ChemStation software lamp intensity and stability diagnostics within the software can aid in diagnosing problems within the optical system which contribute to excessive noise Low intensity in one wavelength range may not preclude you from using the spectrophotometer at another wavelength range where the intensity is acceptable Causes and solutions for excessive noise in part of the spectrum are shown in Table 43 Table 43 Excessive Noise in Part of Spectrum Possible Causes Action One of the lamps may be turned off when making measurements Measurements taken with the deuterium lamp off exhibits excessive noise in the UV wavelength range Measurements taken with the tungsten lamp off exhibits excessive noise in the visible wavelength range Switch on proper lamp Noise in the UV wavelength range may be caused by a weak or defective deuterium lamp Exchange the lamp Lifetime of the deuterium lamp may be influenced by the number of ignitions Flow cells and cuvettes which reduce and or distort the colimated light beam used in the spectrophotomet
3. 114 the SDA board 129 the shutter assembly 102 125 the SLS board 131 the SPM board 121 the tungsten lamp 99 the upper rear foam block 121 reproducibility 12 reset of power supply 33 resident EEPROM 38 part of firmware 43 148 resolution 12 RFI radiated frequency interference 38 ribbon cables on SDA and LPS boards 120 121 RS232C connector 24 58 settings 148 S safety light switches 41 shutdown 41 sample compartment 20 110 111 113 114 pan 110 111 113 114 push button 23 sampling interval 21 scan time 13 SCI board 38 SDA board 30 120 121 exchanging 128 removing 128 replacing 129 security lever 25 sensor for overtemperature 33 setting the 8 bit configuration switch 146 sheet metal door 25 rear cover 114 shine through aperture 19 shortest scan time 13 shutdown 41 shutter 19 20 shutter assembly connector 64 exchanging 124 removing 101 124 replacing 102 125 shutter cable 101 102 120 121 124 125 signal averaging 35 conditioning electronics 45 level 50 SIMM memory module 36 memory modules 118 119 socket 118 sockets 30 single channel peristaltic pump 51 sipper sampler GPIO cable 51 Index 165 sipper GPIO cable 51 slit 19 21 slit width 12 21 slots for MIO and accessory boards 25 SLS board 30 exchanging 130 removing 130 replacing 131 source lens 19 20 cleaning 103 surface 102 103 source of radiation 19 specificatio
4. 118 V valve connector 54 valve controller GPIO cable 54 variance 43 calculation 36 W wavelength accuracy 12 axis linearization 47 calibration table 47 range 12 reproducibility 12 weight 11 width of slit 12 21 wired or technique 50 wrist strap 108 Z zinc argon lamp 47 166 Index sa In This Book This handbook is intended for the technical reader who needs background information about the Agilent 8453 spectrophotometer and potential repairs The handbook contains specifications of the spectrophotometer as well as descriptions of front and back panels for example where to connect accessories Electronics are explained at block diagram level There is a detailed section about troubleshooting to help find a defective subassembly such as an electronic board in case the spectrophotometer does not operate any more Part replacement procedures as well as an exploded view with part numbers are given for ordering and replacing assemblies For information about installation of the system including the spectrophotometer computer and accessories see the Installing Your UV Visible Spectroscopy System handbook
5. 26 Theory of Operation Instrument Layout and Construction Instrument Layout and Construction The industrial design of the spectrophotometer incorporates several innovative features It uses the E Pak concept for the packaging of electronics and mechanical assemblies This concept is based upon the use of layers foam plastic spacers in which the electronic boards of the spectrophotometer are placed This pack is then housed in a metal internal cabinet which is enclosed by a plastic external cabinet The advantages of this packaging technology are the plastic layers have air channels molded in them so that cooling air can be guided exactly to the required locations the plastic layers help cushion the electronical and mechanical parts from physical shock and the metal inner cabinet shields the internal electronics from electromagnetic interference and also helps to reduce or eliminate radio frequency emissions from the instrument itself 27 Theory of Operation Instrument Layout and Construction 28 Theory of Operation and Control This section explains the function of the electronics of the spectrophotometer on block diagram level Each board and or functional group is described in a separate module 29 Theory of Operation Electronics Overview Electronics Overview Figure 4 Electronics Block Diagram The spectrophotometer includes a spectrograph which utilizes a processor controlled photodiode array S
6. Check that the spectrophotometer passes its self test this means that the green light on the front panel comes on and that you can do a blank measurement from your software and the keyboard of the spectrophotometer 118 Maintenance and Repair Exchanging or Upgrading Internal Memory Exchanging or Upgrading Internal Memory Additional memory can be used in the spectrophotometer in case of very fast repetitive measurements of huge amounts of spectra e g for fast kinetics measurements Two sizes of memory are available 1 MByte memory part number 1818 4271 and 4 Mbyte memory part number 1818 5784 You can use the following combinations of memory modules 1 1 MByte 2 2 MByte 1 4 MByte or 2 4 MByte Use the following procedure for removing and replacing memory Removing SIMM Memory Modules 1 Turn off the spectrophotometer and disconnect the power cord Take the plastic and sheet metal rear covers off see Removing and Replacing Covers on page 109 2 Remove any accessory board or MIO board that may be plugged in from the rear side of the instrument Figure 34 Removing MIO or Accessory Boards 3 Remove the upper rear foam block 4 On the two sides of the SIMM socket move the two springs in opposite directions that the memory module is released and you can move the memory module towards the rear of the spectrophotometer 119 Maintenance and Repair Exchanging or Upgrading Internal Memory Figure 35
7. SDA board spectr data acquisition board G1103 69504 33 Sheet metal kit containing chassis bottom metal top front metal top rear metal lamp door are included and shown in Figure 52 G1103 68701 Metal cover screw not shown in Figure 53 5022 2112 35 SLS board spectr lamp supply board G1103 69502 142 Parts and Materials Exploded Views and Part List Figure 54 Front Cover Parts Table 51 Front Cover Parts Breakdown Item Description Part Number 37 Plastic Cover Front G1103 44101 38 Tapping Screw 0515 2734 39 SSI Board G1103 66505 40 Key Pad G1103 44901 37 38 39 40 143 Parts and Materials Exploded Views and Part List Parts not shown in the illustrated parts breakdown are given in Table 52 Table 52 Additional Parts Description Part Number Standard cell holder 08451 60104 Sipper sampler GPIO cable G1103 61608 Multichannel pump GPIO cable G1103 61607 Controller GPIO cable G1103 61610 General purpose GPIO cable G1103 61611 Waste tubing 0890 1711 GPIB cable 1m 10833A APG remote cable start stop error ready shut down power on 5061 3378 Handheld controller with flexible CAN interface cable and documentation G1819A 144 Parts and Materials Exploded Views and Part List 6 6 Interfacing Communicating and interfacing through GPIB and RS 232C 146 Interfacing Setting the 8 Bit Configuration Switch Setting the 8 Bit Conf
8. Solutions of organic acids acetic acid formic acid and so on in organic solvents For example a 1 solution of acetic acid in methanol will attack steel Solutions containing strong complexing agents for example EDTA ethylene diamine tetra acetic acid Mixtures of carbon tetrachloride with 2 propanol or THF 157 Radio Interference Radio Interference Manufacturer s Declaration This is to certify that this equipment is in accordance with the Radio Interference Requirements of Directive FTZ 1046 1984 The German Bundespost was notified that this equipment was put into circulation the right to check the series for compliance with the requirements was granted Test and Measurement If test and measurement equipment is operated with equipment unscreened cables and or used for measurements on open set ups the user has to assure that under operating conditions the radio interference limits are still met within the premises 158 Sound Emission Sound Emission Manufacturer s Declaration This statement is provided to comply with the requirements of the German Sound Emission Directive of 18 January 1991 This product has a sound pressure emission at the operator position lt 70 dB Sound Pressure Lp lt 70 dB A At Operator Position Normal Operation According to ISO 7779 1988 EN 27779 1991 Type Test 159 Lithium Batteries Information Lithium Batteries Information
9. The light source for the VIS and SWNIR wavelength range is a low noise tungsten lamp This lamp emits light over the 370 nm to 1100 nm wavelength range Tungsten lamp Source lens Deuterium lamp Shutter stray light filter Cuvette Photodiode array Source lens Slit Grating 20 Theory of Operation Optical System Overview Source Lens The source lens receives the light from both lamps and collimates it The collimated beam passes through the sample if one is present in the sample compartment Shutter The shutter is electromechanically actuated It opens and allows light to pass through the sample for measurements Between sample measurements it closes to limit exposure of sample to light If the measurement rate is very fast you can command the shutter to remain open ChemStation software or it stays open automatically handheld controller software Stray Light Correction Filter In a standard measurement sequence reference or sample intensity spectra are measured without and then with the stray light filter in the light beam Without the filter the intensity spectrum over the whole wavelength range from 190 1100 nm is measured The stray light filter is a blocking filter with 50 blocking at 420 nm With this filter in place any light measured below 400 nm is stray light This stray light intensity is then subtracted from the first spectrum to give a stray light corrected spectrum Depending on the sof
10. switch settings refer to Chapter 6 Interfacing Using a serial parallel printer cable an HP printer can be connected to the spectrophotometer This option is only used by the Agilent 8453E UV visible spectroscopy system The 8 bit configuration switch has to be set to GPIB communication and not to RS232 communication Table 11 RS232 Connector Pin Function Pin Function 1 DCD 6 DSR 2 RxD 7 RTS 3 TxD 8 CTS 4 DTR 9 RI 5 GND 59 Theory of Operation External Connectors GPIO Connector The GPIO port is a TTL Input Output port which is used to control accessories like the pumps If no other accessory is used the GPIO port can be used to trigger a measurement from an external device The trigger lines use the GPIO connector pins as shown in Table 13 Table 12 GPIO Connector Pin Function Pin Function 1 Out bit 0 9 In bit 0 2 Out bit 1 10 In bit 1 3 Out bit 2 11 In bit 2 4 Out bit 3 12 In bit 3 5 Out bit 4 13 In bit 4 6 Out bit 5 14 In bit 5 7 Out bit 6 15 DGND 8 Out bit 7 Table 13 Trigger Inputs Pin Function 9 Trigger blank measurement 10 Trigger sample measurement 11 Trigger standard measurement 12 Trigger stop 13 Trigger kinetics measurement 15 Ground 60 Theory of Operation External Connectors UV vis ChemStation Software Measurements are activated on contact closure to ground pin 15 By default these trigger li
11. Board SCI Spectrograph Connector Interface Board The PDA which includes control electronics for readout of the individual photodiodes is mounted on the SCI spectrograph connector interface board Gain switching is used to optimize the signal level to the dynamic range of the A D converter on the SDA board In addition wavelength calibration data from the manufacturing process are stored in the resident EEPROM to provide both wavelength precision and accuracy PDA Signal Conditioning Electronics Data is transferred from the photodiode array PDA through the spectrograph connector interface SCI board to the PDA signal conditioning electronics The PDA signal conditioning electronics adjusts the signal levels to provide an appropriate output signal A D Converter The output signal from the PDA signal conditioning electronics is directed to the 16 bit 160 kHz A D converter Multiplexing is used to monitor the signal from the PDA temperature sensor which is used for temperature compensation PFP PDA Front End Processor The PDA front end processor PFP utilizing an on board RAM and the EPLD electronically programmable logic device forwards the data from the 16 bit A D converter to the SPM board It provides timing and control for the photodiode readout and the A D conversion Low Pass Filter Signals between the SPM board and the switches and LED on the spectrophotometer sipper interface SSI board are routed through a
12. Removing SIMM Memory Modules 5 Remove the memory module and repeat the last step in case there is a second memory module installed Replacing SIMM Memory Modules 1 Place the memory module in the SIMM socket on the SPM board that the components of the memory module are facing to the rear of the spectrophotometer The memory module is now positioned at an angle in the SIMM socket 2 Press the memory module towards the front of the spectrophotometer that it snaps in behind the two springs on either side of the SIMM socket 3 Replace the upper rear foam block 4 If available replace any accessory board or MIO board plugged in from the rear side of the instrument 5 Replace the plastic and sheet metal rear cover Push the plastic rear cover down so that it locates on both sides see Removing and Replacing Covers on page 109 6 Reconnect line power and turn on the instrument Check that the spectrophotometer passes its self test this means that the green light on the front panel comes on and that you can do a blank measurement from your software SIMM memory modules 120 Maintenance and Repair Exchanging the SPM Board Exchanging the SPM Board The spectrograph processor board SPM board part number G1103 69500 is located in the top rear part of the spectrophotometer Removing the SPM Board 1 Turn off the spectrophotometer and disconnect the power cord Take the plastic and sheet metal rear covers off see Remo
13. Replacing Sample Pan and Cuvette Holder 4 Replace the plastic cover and push it down so that it locates on both sides 5 Reconnect line power and turn on the instrument Check that the spectrophotometer passes its self test this means that the green light on the front panel comes on and that you can do a blank measurement from your software 116 Maintenance and Repair Exchanging Keyboard and Key Pad Exchanging Keyboard and Key Pad The keyboard is part of the plastic front cover and comprises the key pad part number G1103 44901 and the spectrophotometer sipper interface SSI board part number G1103 66505 Removing Keyboard and Key Pad 1 Turn off the spectrophotometer and disconnect the power cord Take the plastic front cover off see Removing and Replacing Covers on page 109 and disconnect the cable to the SSI board 2 Open the screws that hold the SSI board in place and remove the SSI board and the keypad Figure 33 Exchanging Keyboard and Keypad Replacing Keyboard and Key Pad 1 Position the key pad and the keyboard inside the front cover and tighten the screws that hold the keyboard in place see Figure 33 2 Connect the cable to the SSI board Replace the plastic cover and push it down so that it locates on both sides see Removing and Replacing Covers on page 109 Key pad Keyboard 117 Maintenance and Repair Exchanging Keyboard and Key Pad 3 Reconnect line power and turn on the instrument
14. Table 20 Multicell Transport Home Position Not Found Possible Causes Action The multicell transport mechanism is jammed Make sure the carriage can move freely along its entire path and that there are no obstructions Check that the two screws which fix the multicell transport in the spectrophotometer are not pushed up into the path of the mechanism e g this is the case when putting the transport beside the instrument Electronics failed Check for defective HOME switch defective multicell transport cable defective motor or defective spectrophotometer processor main SPM board Table 21 Lamp Door Open Lamps Are Switched Off Possible Causes Action Lamp door is open Close lamp door Lamp door is bent Light switch tab is positioned incorrectly Bend light switch tab on lamp door to correct tab position Light switch or electronics have failed Replace spectrophotometer lamp power supply SLS board 73 Diagnostics and Troubleshooting Error Messages Table 22 Invalid Data Points In Spectrum Possible Causes Action Blank has higher absorbance than sample measurement Solvent or chemical matrix of blank has higher absorbance than solvent matrix of sample Ensure sample and blank use the same solvent or chemical matrix Measure blank on water In kinetics mode of ChemStation software 1 Under Options amp Information in the Method menu select Adjust gains separately from blank measuremen
15. The instrument specific part of the firmware is used to supervise interface control for multicell transport GPIO lines and APG remote MIO board and accessory board control internal events such as lamp turn on cycle and shutter and filter movements diagnostic functions and raw data conversion to absorbance Raw Data Conversion to Absorbance The raw data flow from the photodiode array and conversion to absorbance spectra with variance for each data point is a multiple step process This process is outlined in this section 44 Theory of Operation Firmware Description Figure 10 Firmware Flow Diagram 45 Theory of Operation Firmware Description Subtract Dark Current Raw data coming from the photodiode array through the signal conditioning electronics which includes a variable gain amplifier are read from the A D converter see on page 37 This raw data are intensity values of each photodiode of the array During a blank measurement a dark current and electronic offset measurement is performed for every diode on the photodiode array This offset spectrum is stored and subtracted from all subsequent intensity spectra to give dark corrected intensity spectra Gain Correction Also during a blank measurement every photodiode is assigned a gain value depending of the amount of light falling on the diode array These gain values are stored in a table They are used to adjust t
16. a flow cell or thermostattable cell holder The spectrophotometer is shipped with the standard single cell cell holder Standard and accessory cell holders can be removed and replaced in seconds with few or no tools Figure 2 Front View of Spectrophotometer The line power switch is located at the lower left part of the instrument Pressing it in turns on the instrument It stays pressed in and shows a green light when the instrument is turned on When the line power switch stands out and the green light is off the instrument is turned off On the front panel of the spectrophotometer is a status indicator which will display different colors depending of the actual condition of the instrument Indicator Pushbuttons Line power switch with green light 23 Theory of Operation Instrument Description Green the instrument is ready to measure Green blinking the instrument is measuring Yellow the instrument is in not ready state for example turning one of the lamps on or if both lamps are switched off Red error condition that is the spectrophotometer does not pass one of the self tests which are run when the spectrophotometer is turned on or an error occurred during operation In this case the UV Visible operating software gives a detailed error message and possible explanations are in the online help system and in Chapter 3 Diagnostics and Troubleshooting Red blinking error condition
17. before repair WARNING To disconnect the instrument from line pull out the power cord The power supply still uses some power even if the power switch on the front panel is turned off For exchange of electronic assemblies we recommend to use an antistatic grounding kit part number 9300 0933 to prevent the electronics from damage by electrostatic discharge Before you unpack any electronic replacement parts connect yourself electrically to the instrument with the help of a wrist strap Connect the packing material with the electronic replacement part to the instrument Touch electronic boards only on the corners and avoid touching the metal traces and electronic items on the board When you remove electronic assemblies from the instrument always put them back into the antistatic bags or place them on a material that has an electrical connection to the instrument 109 Maintenance and Repair Removing and Replacing Covers Removing and Replacing Covers Use the following procedures to access the electronic items in case of a repair and for troubleshooting reasons Removing the Front Covers 1 Turn off the spectrophotometer and disconnect the power cord 2 To remove the plastic front cover hold the plastic cover on the lower edge with two hands from the left and right of the instrument Pull the lower edges of the cover in opposite directions and simultaneously lift up Figure 21 Removing the Plastic Fr
18. changes in the refractive index from BLANK to SAMPLE Measure Blank on the same solvent as used for the sample Wedge shaped cuvettes low quality cuvettes mostly not always plastic cuvettes there are non wedge shaped plastic cuvettes available Use high quality quartz cuvettes Bubbles in the cell even very small ones are sufficient to create spikes Try to get rid of the bubbles by gently knocking the cell on a desk Rinsing the cells with a cleaning and pasivating solution makes the bubbles less sticky to the windows Sometimes the use of degassed solvent prevents the building of bubbles and make to time between filling the cells and the measurement as short as possible Floating particles in the cell from cleaning tissues or the application or other kind of dirt Cells have to be cleaned using cleaning and pasivating solution Use optical tissues to wipe the outer surface of the cells Any kind of addionally mounted optical devices put into the light path of the instrument The manipulation of the optical characteristics can cause some decrease in optical performance No corrective action execpt the remove of the optical active device can change the behavior Turbid samples especially in kinetics when a mixing process occurs during measurement Avoid turbidity e g by filtration 89 Diagnostics and Troubleshooting General Troubleshooting Hints Apertured cells For single cell holder For cel
19. jumper to 15 15 3 DGND means active low negative true logic 52 Theory of Operation External Cables and the autosampler to the GPIO connector at the rear of your spectrophotometer Table 5 Sipper Sampler GPIO Cable G1103 61608 GPIO Connector Pump Connector Autosampler Connector Function Out 1 1 Direction counter clockwise 2 2 Pump on clockwise 3 2 Advance tray 4 3 Raise pipette 5 4 Lower pipette 6 5 Pipette to sample 7 6 Pipette to wash In 9 10 Rack in motion 10 11 Stop position 11 12 Pipette up 12 13 Pipette down 13 14 Pipette to sample 14 Status jumper to 15 15 3 1 DGND means active low negative true logic 53 Theory of Operation External Cables Multichannel Pump GPIO Cable The multichannel pump GPIO cable part number G1103 61607 is used to connect the 8 channel peristaltic pump to the GPIO connector at the rear panel of your spectrophotometer Table 6 Multichannel Pump Cable G1103 61607 GPIO Connector Pump Connector Function 1 4 Direction counter clockwise 2 3 Pump on clockwise 14 Status jumper to 15 15 1 2 connected DGND means active low negative true logic 54 Theory of Operation External Cables Valve Controller GPIO Cable The valve controller GPIO cable part number G1103 61610 is used to connect the valve pump controller to the G
20. mercury lamp 47 metal front cover 111 internal cabinet 26 lamp door 96 99 microprocessor 35 system 43 MIO board control 43 removing 118 120 slot 25 mode select 146 multicell transport connector 24 57 multichannel pump GPIO cable 53 N NIST 2034 standard 12 14 NIST 930e standard 12 14 noise 13 nominal spectral slit width 21 non volatile random access memory NVRAM 35 146 NVRAM 35 O offset correction 35 open collector type 50 operating altitude 11 temperature 11 optical system 19 optical tissue 98 optical unit 122 exchanging 122 removing 122 replacing 123 overload 32 overtemperature sensor 33 overview of electronics 29 of optical system 19 P parity settings 149 parts 138 breakdown 139 141 front cover 142 list 138 numbers 138 PDA photodiode array 38 front end processor PFP 38 signal conditioning electronics 38 performance specifications 12 peripherals connections to 50 peristaltic pump 51 personal computers 10 photodiode array 21 30 38 45 quantum efficiency 45 temperature compensation 35 photographic lenses 102 104 cleaning brush 102 104 105 photometric accuracy 12 noise 13 stability 13 physical specifications 11 plasma discharge 19 plastic door 25 164 Index external cabinet 26 front cover 109 112 lamp door 96 99 potassium dichromate 12 power button 134 power consumption 11 power supply cable 63 program memo
21. on if measurement over whole spectral range is required If spectra in the UV range only are being measured then deuterium lamp must be on If spectra in the Visible range only are being measured then tungsten lamp must be on Weak lamp Use diagnostics intensity test to check if lamp intensity is too low and change lamp if necessary 4 4 Maintenance and Repair Procedures for exchanging parts such as lamps and electronic or mechanical items and for cleaning lenses 94 Maintenance This section describes maintenance procedures such as cleaning the instrument exchanging the deuterium and tungsten lamps and cleaning lenses Always disconnect the instrument from line power before maintenance WARNING To disconnect the instrument from line pull out the power cord The power supply still uses some power even if the power switch on the front panel is turned off 95 Maintenance and Repair Cleaning the Instrument Cleaning the Instrument The spectrophotometer case and sample compartment should be kept clean Cleaning should be done with a soft cloth slightly dampened with water or a solution of water and a mild detergent Do not use an excessively damp cloth that liquid can drip into the spectrophotometer WARNING Do not let liquid drip into the instrument It could cause shock hazard and it could damage the instrument 96 Maintenance and Repair Exchanging the Deuterium or Tungsten Lamp Exchanging the Deuterium
22. or Tungsten Lamp You exchange the deuterium or the tungsten lamp when the intensity test which is executed through your software falls below the specified level or when one of the lamps no longert ignites Removing the Deuterium or Tungsten Lamp 1 Turn off the spectrophotometer and disconnect the power cord 2 Open the plastic lamp door at the right side of the instrument Figure 11 Opening the Plastic Lamp Door 3 To open the metal door behind the plastic door slide the lock mechanism down and simultaneously pull the door out 97 Maintenance and Repair Exchanging the Deuterium or Tungsten Lamp Figure 12 Opening the Metal Lamp Door 4 Slide the metal door out to have access to the lamps WARNING The light emitted by the deuterium lamp in this instrument may cause damage to the naked eye Always turn off the deuterium lamp before removing the deuterium lamp Figure 13 Sliding Out the Metal Lamp Door 5 To disconnect the lamp cables press the plug which connects the tungsten or deuterium lamp to the printed circuit together on both sides and lift it up 98 Maintenance and Repair Exchanging the Deuterium or Tungsten Lamp Figure 14 Disconnecting the Lamp Cables and Removing the Lamps WARNING If you have been using the instrument the lamp may be hot Wait five minutes until the lamp cools down Further a hot lamp collects dust when taking it out In case you reuse the lamp this dust would enter the optical
23. page 14 Upon request of the operator through the user interface of the software the new parameters are used together with the wavelength calibration table to calculate a table of correction coefficients which are applied to each spectrum 49 Theory of Operation Firmware Description 50 External Communication This section gives the definition of the connections to the computer and peripherals of the spectrophotometer Connectors with pin assignments and cables are described in detail WARNING Only use cables supplied by Agilent Technologies to make sure the instrument functions properly and complies with safety or EMC regulations The signal levels are defined as standard TTL levels 0 V is logic true 5 V is false Input load is 2 2 kOhm against 5 V Output are open collector type inputs outputs wired or technique 51 Theory of Operation External Cables External Cables Sipper GPIO Cable The sipper GPIO cable part number G1103 61609 is used to connect the single channel peristaltic pump to the GPIO connector at the rear of your spectrophotometer Sipper Sampler GPIO Cable The sipper sampler GPIO cable part number G1103 61608 is a cable with three connectors It is used to connect the single channel peristaltic pump Table 4 Sipper GPIO Cable G1103 61609 GPIO Connector Pump Connector Function 1 1 Direction counter clockwise 2 2 Pump on clockwise 14 Status
24. problem with your instrument Refer to Table 36 through Table 41 for further troubleshooting information Table 36 Power Switch LED Off Front Panel LED Off Possible Causes Action Instrument power disconnected Connect instrument to power Overcurrent or overvoltage condition Spring below optical unit may be bent This may result in a short circuit on the SDA board Remove optical unit Bend spring back and turn instrument off and on again to reset main power supply Overcurrent or overvoltage condition Electronics failure Turn instrument off and on again to reset main power supply If the error condition remains disconnect internal boards one by one repetitively turning the instrument off and on to find the defective board Main power supply MPS defective Replace main power supply MPS Table 37 Power Switch LED Off Front Panel LED On Possible Cause Action LED in main power supply MPS defective Replace main power supply MPS Table 38 Power Switch LED On Front Panel LED Off Shutter Clicks Possible Causes Action Front panel keyboard SSI board disconnected or cable defective Reconnect or replace cable Front panel keyboard SSI board defective Replace front panel keyboard SSI board 82 Diagnostics and Troubleshooting General Troubleshooting Hints Table 39 Power Switch LED On Front Panel LED Off Shutter Does Not Click Possible Causes Action 8 bit conf
25. used Instrument start up tests are implemented in the spectrophotometer firmware They are used to check if the instrument electronics are functioning during start up and operation of the instrument and create error messages or symptoms on the front panel status LEDs Self test and diagnostic tests are implemented in the operating software For explanation of these tests see your software documentation and online help in the software This chapter covers the following topics related to troubleshooting the spectrophotometer front panel status and power switch LEDs error messages and general troubleshooting hints This chapter gives information about how to troubleshoot the instrument For detailed procedures about cleaning lenses disassembling the spectrophotometer and exchanging individual electronic items see Chapter 4 Maintenance and Repair 69 Diagnostics and Troubleshooting Front Panel Status and Power Switch LEDs Front Panel Status and Power Switch LEDs A general description of the functionality of the status and power switch LEDs is given in Chapter 2 Theory of Operation This section describes typical LED symptoms in case of failures of the instrument Power switch LED off The line power switch with the power switch LED is located at the lower left part of the instrument If the line power switch is pressed in but the green light is off the instrument may not be connected to line
26. 0 1 148 Interfacing Setting the 8 Bit Configuration Switch If you use the following switch settings and power the instrument up again the instrument firmware stays in the resident part that is it is not operable as a spectrophotometer but only uses basic functions of the operating system for example for comunication and so on To return to normal operation set switches back to your GPIB or RS 232 configuration settings Comunication Settings for RS232 Comunication The comunication protocol used in this instrument supports only hardware handshake CTS RTR Switches 1 in down and 2 in up position define that the RS232 parameters will be changed Once the change has been completed the instrument must be powered up again in order to store the values in the non volatile memory Use the following tables for selecting the setting which you want to use for RS232 comunication The number 0 means that the switch is down and Table 55 Stay Resident Settings Mode Select 1 2 3 4 5 6 7 8 TEST BOOT 1 1 0 0 1 0 0 0 Table 56 Communication Settings for RS232 Communication Mode Select 1 2 3 4 5 6 7 8 RS 232 0 1 Baudrate Data Bits Parity 149 Interfacing Setting the 8 Bit Configuration Switch 1 means that the switch is up Please note that there are two possible switch settings for 9600 baud Table 57 Baudrate Settings Switches Baud Rate Switches Baud Rate 3 4 5 3 4 5 0 0 0 96
27. 00 1 0 0 9600 0 0 1 1200 1 0 1 14400 0 1 0 2400 1 1 0 19200 0 1 1 4800 1 1 1 38400 Table 58 Data Bit Settings Switch 6 Data Word Size 0 7 Bit Comunication 1 8 Bit Comunication Table 59 Parity Settings Switches Parity 7 8 0 0 No Parity 1 0 Odd Parity 1 1 Even Parity 150 Interfacing Setting the 8 Bit Configuration Switch 151 Warranty Statement Warranty Statement All Chemical Analysis Products Agilent Technologies Agilent warrants its chemical analysis products against defects in materials and workmanship For details of the warranty period in your country call Agilent During the warranty period Agilent will at its option repair or replace products which prove to be defective Products that are installed by Agilent are warranted from the installation date all others from the ship date If buyer schedules or delays installation more than 30 days after delivery then warranty period starts on 31st day from date of shipment 60 and 61 days respectively for products shipped internationally Agilent warrants that its software and firmware designed by Agilent for use with a CPU will execute its programming instructions when properly installed on that CPU Agilent does not warrant that the operation of the CPU or software or firmware will be uninterrupted or error free Limitation of Warranty Onsite warranty services are provided at the initial installati
28. CE LC UV visible supplies and accessories 90 Days Onsite Columns and consumables 90 Days Return to Agilent Gas discharge and tungsten lamps 30 Days Return to Agilent Repairs performed onsite by Agilent 90 Days Onsite This warranty may be modified in accordance with the law of your country Please consult your local Agilent office for the period of the warranty for shipping instructions and for the applicable wording of the local warranty Warranty services are included as specified for chemical analysis products and options purchased concurrently provided customer is located within a Agilent defined travel area Agilent warranty service provides for 8 a m to 5 p m onsite coverage Monday through Friday exclusive of Agilent holidays Columns and consumables are warranted to be free from defects for a period of 90 days after shipment and will be replaced on a return to Agilent basis if unused Agilent repair warranty is limited to only the item repaired or replaced 154 Safety Information Safety Information The following general safety precautions must be observed during all phases of operation service and repair of this instrument Failure to comply with these precautions or with specific warnings elsewhere in this manual violates safety standards of design manufacture and intended use of the instrument Agilent Technologies assumes no liability for the customer s failure to comply with these requirem
29. Dampen a lint free surgical cotton swab with reagent grade isopropanol isopropyl alcohol and gently swab the surface of the stray light filter Repeat several times with clean swabs and alcohol each time 2 Use a canister of compressed oil free air like those used to clean photographic lenses to further clean the stray light filter If you do not have a compressed air canister you can use a photographic lens cleaning brush Replacing the Shutter Assembly 1 Position the shutter assembly above the source lens and fix the screw that holds it at the optical unit see Figure 39 Connect the shutter cable to the SPM board 2 Replace the upper rear and upper front foam blocks 3 If available replace any accessory board or MIO board plugged in from the rear side of the instrument 4 Replace the plastic and sheet metal rear covers Push the plastic rear cover down so that it locates on both sides see Removing and Replacing Covers on page 109 5 Reconnect line power and turn on the instrument Check that the spectrophotometer passes its self test this means that the green light on the front panel comes on and that you can do a blank measurement from your software 103 Maintenance and Repair Cleaning the Lenses Cleaning the Lenses Cleaning the lenses which are accessible from the sample compartment is recommended at one yearly intervals or more frequently when you operate the spectrophotometer in a particularly dirty envi
30. OVIDED HEREIN ARE BUYER S SOLE AND EXCLUSIVE REMEDIES IN NO EVENT SHALL AGILENT BE LIABLE FOR DIRECT INDIRECT SPECIAL INCIDENTAL OR CONSEQUENTIAL DAMAGES INCLUDING LOSS OF PROFITS WHETHER BASED ON CONTRACT TORT OR ANY OTHER LEGAL THEORY Responsibilities of the Customer The customer shall provide 1 access to the products during the specified periods of coverage to perform maintenance 2 adequate working space around the products for servicing by Agilent personnel 3 access to and use of all information and facilities determined necessary by Agilent to service and or maintain the products insofar as these items may contain proprietary or classified information the customer shall assume full responsiblity for safeguarding and protection from wrongful use 4 routine operator maintenance and cleaning as specified in the Agilent operating and service manuals and 5 consumables such as paper disks magnetic tapes ribbons inks pens gases solvents columns syringes lamps septa needles filters frits fuses seals detector flow cell windows and so on 153 Warranty Statement Responsibilities of Agilent Technologies Agilent Technologies will provide warranty services as described in the following table Table 60 Warranty Services Services During Warranty Warranty Period Type Agilent CE instruments Agilent 1100 Series LC modules Agilent 8453 UV visible spectrophotometers 1 Year Onsite
31. PIO connector at the rear panel of your spectrophotometer General Purpose GPIO Cable The general purpose GPIO cable part number G1103 61611 has only a connector on the spectrophotometer side It is used to connect any custom made device with parallel I O to the GPIO connector at the rear panel of your spectrophotometer Table 7 Valve Controller GPIO Cable G1103 61610 Valve Connector GPIO Connector Function Out 1 15 DGND 2 1 A0 3 2 A1 4 3 A2 5 9 D0IN 6 10 D1IN 7 11 D2IN 8 4 R W In 9 5 DV 12 12 Rdy 13 6 D0OUT 14 7 D1OUT 15 8 D2OUT means active low negative true logic 55 Theory of Operation External Cables Table 8 General Purpose Cable G1103 61611 Pin Function Pin Function 1 OUT 0 9 IN 0 2 OUT 1 10 IN 1 3 OUT 2 11 IN 2 4 OUT 3 12 IN 3 5 OUT 4 13 IN 4 6 OUT 5 14 IN 5 7 OUT 6 15 DGND 8 OUT 7 56 Theory of Operation External Connectors External Connectors GPIB Connector The GPIB core design is used as talker listener and a controller which is usually the computer with Agilent ChemStation software loaded It supports all GPIB functionality except passing control between different devices The connector needs to be activated and configured by the 8 bit configuration switch next to the GPIB connector For switch settings refer to the Installing Your UV Visible
32. SSI Board The SSI board controls the push buttons and the LED located at the front panel of the instrument Figure 9 SSI Board Switches are pulled to GND when pressed and provide a signal to the SPM board through the low pass filter on the SDA board The LED is driven from the SPM board through the low pass filter on the SDA board 43 Theory of Operation Firmware Description Firmware Description The firmware of the instrument comprises two parts One part is used by the MP 68332 processor on the SPM board that is to boot the instrument and use the basic functions of the processor for memory control and input output control The other part for the DSP on the SPM board is used to make the instrument operate as a spectrophotometer Firmware updates of the instrument specific part can be done by a download procedure from the computer Updates will be provided on flexible disk Resident Part of the Firmware If the instrument is configured to stay in the resident part of the firmware it does not react as a spectrophotometer but uses only the basic functionality of the microprocessor system In this case the firmware is used to establish the communication to the computer that is for data communication through the GPIB CAN and RS232 interfaces For reseting the instrument that it stays in the resident part of the firmware and forced cold start see Chapter 6 Interfacing Instrument Specific Part of the Firmware
33. Spectroscopy System handbook APG Remote Connector Remote control allows easy connection between single instruments or systems to ensure coordinated analysis with simple coupling requirements A subminiature D connector is used The module provides one remote connector which is inputs outputs wired or technique To provide maximum safety within a distributed analysis system one line is dedicated to SHUT DOWN the system s critical parts in case any module detects a serious problem To detect whether all participating modules are switched on or properly powered one line is defined to summarize the POWER ON state of all connected modules Control of analysis is maintained by signal readiness READY for next analysis followed by START of run and optional STOP of run triggered on the respective lines In addition PREPARE and START REQUEST may be issued Table 9 APG Remote Signal Distribution Pin Signal Function 1 DGND Digital ground 2 PREPARE L Request to prepare for analysis e g calibration detector lamp on Receiver is any module performing preanalysis activities 3 START L Request to start run timetable Receiver is any module performing runtime controlled activities 57 Theory of Operation External Connectors Multicell Transport Connector 4 SHUT DOWN L System has serious problem Receiver is any module capable to reduce safety risk 5 Not used 6 POWER ON H All modules connected tosyste
34. WARNING Danger of explosion if battery is incorrectly replaced Replace only with the same or equivalent type recommended by the equipment manufacturer Do not dispose of lithium batteries in domestic waste Transportation of discharged lithium batteries through carriers regulated by IATA ICAO ADR RID IMDG is not allowed Discharged lithium batteries must be disposed of locally according to national waste disposal regulations for batteries 160 Agilent Technologies on Internet Agilent Technologies on Internet For the latest information on products and services visit our worldwide web site on the Internet at http www agilent com go chem Index 161 Numerics 1 MByte memory 118 16 bit A D converter 31 4 Mbyte memory 118 8 bit configuration switch 146 8 channel peristaltic pump 53 A A D converter 31 absorbance averaging 46 calculation 35 46 47 conversion of raw data to 43 run buffer 46 spectra 46 accessing lamps 25 accessory boards control 43 removing 118 120 accessory slot 25 accuracy photometric 12 wavelength 12 acquisition of spectra 46 additional memory 118 air compressed 104 altitude 11 analog to digital converter 31 antistatic bags 108 grounding kit 108 APG remote connector 56 application specific integrated circuit ASIC 35 ASIC 35 attaching the light pipe to main power supply 135 the power button 134 autosampler 52 connector 52 averaging of intensity sp
35. air Procedures for exchanging parts such as lamps and electronic or mechanical items and for cleaning lenses 93 Maintenance 94 Cleaning the Instrument 95 Exchanging the Deuterium or Tungsten Lamp 96 Cleaning the Stray Light Filter 101 Cleaning the Lenses 103 Repair Procedures 108 Removing and Replacing Covers 109 Exchanging Keyboard and Key Pad 116 Exchanging or Upgrading Internal Memory 118 Contents 7 Exchanging the SPM Board 120 Exchanging the Optical Unit 122 Exchanging the Shutter Assembly 124 Exchanging the Fan Assembly 126 Exchanging SDA Board 128 Exchanging SLS Board 130 Exchanging the Main Power Supply 133 5 Parts and Materials Exploded views of repairable parts and part number listings for ordering replacement and exchange parts 137 Exploded Views and Part List 138 6 Interfacing Communicating and interfacing through GPIB and RS 232C 145 Setting the 8 Bit Configuration Switch 146 8 Contents 1 1 Specifications Specifications of the Agilent 8453 UV visible spectrophotometer 10 Specifications The Agilent 8453 spectrophotometer is a single beam microprocessor controlled UV visible spectrophotometer with collimating optics With its diode array technology the spectrophotometer is much faster than comparable conventional instruments with more precision more sensitivity and more reproducible results Accessories include special cell holders peristaltic pumps auto
36. appropriate level and converted to digital values by a 16 bit A D converter In addition the SDA board controls the timing of the photodiode array The firmware automatically converts data points which are taken at a 0 9 nm sampling interval from the diode array to deliver values at 1 nm interval to the controller SSI Spectrophotometer Sipper Interface Board This board collects the signals from the push buttons and controls the three color LED located on the front panel of the spectrophotometer 32 Theory of Operation The Main Power Supply Assembly The Main Power Supply Assembly The main power supply MPS comprises a closed assembly no onsite repair possibility The power supply provides all DC voltages used in the spectrophotometer except for the voltages supplied by the lamp power supply to the deuterium and tungsten lamps Figure 5 Main Power Supply MPS Block Diagram WARNING To disconnect the instrument from line pull out the power cord The power supply still uses some power even if the power switch on the front panel is turned off No accessible hardware fuse is needed because the main power supply is safe against any shortages or overload conditions on the output lines When overload conditions occur the power supply turns off all output voltages 33 Theory of Operation The Main Power Supply Assembly Turning the line power off and on again resets the power supply to normal operation if the c
37. ause of the overload condition has been removed An overtemperature sensor in the main power supply is used to turn off output voltages if the temperature exceeds the acceptable limit for example if the cooling fan of the instrument fails To reset the main power supply to normal operating conditions turn the instrument off wait until it is approximately at ambient temperature and turn the instrument on again Table 3 gives the specifications of the main power supply Table 3 Main Power Supply Specifications Function Specification Comment Line input 100 120 or 220 240 V AC 10 Wide ranging Line frequency 50 or 60 Hz 5 Output 1 24 V 4 5 A Output 2 36 V Not used Output 3 5 V 3 A Output 4 15 V 0 3 A Output 5 15 V 0 3 A 34 Theory of Operation Spectrophotometer Processor Main SPM Board Spectrophotometer Processor Main SPM Board Figure 6 SPM Board 4 control LEDs 8 bit switch HPIB driver CAN driver GPIO driver RS232 driver multicell transport driver APG remot e ASIC application specific integrated circuit main microprocessor SSP spectra and signal processor SIMM memory module ASIC RAM real time clock battery PWM driver LEDs and switches serial bus SSP bus control lines sense serial bus SPM memory MPS mainpower supply SDA board shutter fan SLS boa
38. cessor SSP Spectra and Signal Processor The spectra and signal processor SSP uses a dedicated ASIC and RAM of 3 128 KB and converts the 1024 raw data values from the SDA board to intensity and absorbance values Conversion and subsequent calculation to achieve absorbance values include the following tasks listed in the sequence of processing 1 dark current correction 2 offset correction 3 PDA temperature compensation 4 stray light correction 5 absorbance calculation 6 signal averaging over integration time and 36 Theory of Operation Spectrophotometer Processor Main SPM Board 7 variance calculation Communication between the spectra and signal processor SSP and the PDA front end processor PFP on the SDA board is established by a serial communication link Processed data and synchronization signals for the PFP clock frequency are exchanged through the serial bus SIMM Memory Module The SIMM memory module controlled by the dedicated ASIC is used to expand the memory to 2 MB add 1 MB module part number 1818 4271 or 2 4 MB part number 1818 5784 to accomodate more spectra Firmware For an outline of the firmware see Firmware Description on page 43 37 Theory of Operation Spectrophotometer Data Acquisition SDA Board Spectrophotometer Data Acquisition SDA Board Figure 7 SDA Board 38 Theory of Operation Spectrophotometer Data Acquisition SDA
39. ctrograph The spectrograph lens refocuses the collimated light beam after it has passed through the sample Slit The slit is a narrow aperture in a plate located at the focus of the spectrograph lens It is exactly the size of one of the photodiodes in the photodiode array By limiting the size of the incoming light beam the slit makes sure that each band of wavelengths is projected onto only the appropriate photodiode Grating The combination of dispersion and spectral imaging is accomplished by using a concave holographic grating The grating disperses the light onto the diode array at an angle proportional to the wavelength Diode Array The photodiode array is the heart of the spectrograph It is a series of 1024 individual photodiodes and control circuits etched onto a semiconductor chip With a wavelength range from 190 nm to 1100 nm the sampling interval is nominal 0 9 nm 22 Theory of Operation Instrument Description Instrument Description Your spectrophotometer is very easy to use It has a line power indicator a status indicator and some push buttons All electrical connections are made at the rear of the instrument Front View The front view of the spectrophotometer is shown in Figure 2 Notice that the sample compartment is open Unlike conventional instruments the Agilent 8453 does not suffer from ambient stray light The open sample area makes it easier to access for cuvette handling and to connect tubing to
40. e an interpolation algorithm is applied This algorithm uses a wavelength calibration table and actual wavelength data derived from the deuterium emission lines at 486 nm and 656 nm Wavelength calibration is done for each individual spectrograph during the production process using emission lines of a mercury lamp deuterium lamp and a zinc argon lamp The individual calibration coefficients are 48 Theory of Operation Firmware Description stored in the wavelength calibration table in an EEPROM electrically erasable PROM which is part of the spectrograph electronics During each start up of the spectrophotometer each discrete wavelength value is assigned to a photodiode of the array Recalibration of the wavelength scale can be performed to compensate for minor deviations from initial production conditions Recalibration is achieved using the deuterium line data that is the exactly known positions of the deuterium emission lines at 486 0 nm and 656 1 nm Because of the real pass band function of the spectrophotometer which is different from the theoretical one the maximum positions of the two emission lines cannot be used Instead the line centroids are used for the calibration recalibration process A description of this method is given in section Wavelength Calibration in Appendix A of NBS Publication 260 66 from NIST National Institute of Standards and Technology For the address of NIST see Source of Standards on
41. e front panel comes on and that you can do a blank measurement from your software 5 5 Parts and Materials Exploded views of repairable parts and part number listings for ordering replacement and exchange parts 138 Parts and Materials Exploded Views and Part List Exploded Views and Part List Parts are listed in the respective tables with their part numbers Assemblies shown do not contain any parts around them unless otherwise specified Figure 52 Spectrophotometer Upper Parts 1 inside parts shown in detail on next pages 2 3 7 8 11 4 6 9 5 14 16 15 12 13 10 25 27 139 Parts and Materials Exploded Views and Part List Table 49 Instrument Parts Breakdown Item Description Part Number 1 Plastic cover front G1103 44101 2 Plastic cover rear G1103 68706 Name plate not shown in Figure 52 G1103 44300 3 4 5 Sheet metal kit containing Metal top front metal top rear metal lamp door chassis bottom is included and shown in Figure 53 G1103 68701 Metal cover screw not shown in Figure 52 5022 2112 5 Metal lamp door G1103 00301 6 7 16 EPP foam parts kit containing Foam front top foam rear top foam rear middle foam front bottom and foam rear bottom are included and shown in Figure 53 G1103 68702 8 Sample pan G1103 44501 9 SPM board spectr proccessor main board G1103 69500 10 Tungsten lamp G1103 60001 11 Scr
42. e between SDA board and SPM board disconnected or defective Reconnect or replace cable Communication error between the main processor and one of the digital signal processors located on the SPM or SDA board Electronics failed Replace spectrophotometer processor main SPM board Replace the spectrophotometer data acquisition SDA board 77 Diagnostics and Troubleshooting Error Messages Table 31 Wavelength Calibration Data Invalid Possible Causes Action Communication error between EEPROM of spectrograph and SDA board Cable between spectrograph and SDA board disconnected or defective Reconnect or replace cable Wavelength calibration data from EEPROM of spectrograph rejected or communication of calibration data disrupted Replace the spectrophotometer data acquisition SDA board Wavelength calibration data in EEPROM of spectrograph corrupted Replace optical unit Table 32 Wavelength Recalibration Data Lost Possible Causes Action 8 bit configuration switch sets the instrument to resident mode Correct 8 bit configuration switch settings and turn instrument off then on again Perform a wavelength recalibration with your software When doing a firmware upgrade wavelength recalibration data are lost The factory wavelength calibration is still valid Perform a wavelength recalibration with your software When exchanging the SPM board wavelength recalibration data are lost The factory
43. ectra 46 of signal data 35 B baseline flatness 13 battery for NVRAM 35 baudrate settings 149 binary code of GPIB address 146 blank push button 23 block diagram of electronics 29 of main power supply 32 of SLS board 39 of SPM board 34 of SSI board 42 boards spectrograph connector interface SCI 38 spectrophotometer data acquisition SDA 30 spectrophotometer interface SSI 42 spectrophotometer lamp supply SLS 30 spectrophotometer processor main SPM 30 spectrophotometer sipper interface SSI 30 31 38 109 116 burn hazard 98 C cabinet 26 cables 51 general purpose GPIO 54 multichannel pump GPIO 53 power supply 63 sipper sampler GPIO 51 sipper GPIO 51 valve controller GPIO 54 calculation of absorbance 35 46 47 of variance 36 CAN connector 25 58 certification of computers 10 chassis of instrument 122 123 cleaning lenses 94 the Instrument 95 the instrument 94 the lenses 103 the source lens 103 the spectrograph lens 105 clock 35 collimated beam 19 compartment for sample 20 compensation for photodiode array temperature 35 compressed air 104 computers 10 connections to 50 comunication protocol 148 comunication settings for RS232 comu nication 148 connecting plugs of lamps 99 connections internal 62 to computer 50 to peripherals 50 connector APG remote 56 autosampler 52 CAN 25 58 definitions 63 fan 63 GPIB 25 GPIO 24 51 52 53 ma
44. ectrophotometer passes its self test this means that the green light on the front panel comes on and that you can do a blank measurement from your software 133 Maintenance and Repair Exchanging the Main Power Supply Exchanging the Main Power Supply The main power supply MPS part number 0950 2528 is located below the SPM board in the rear part of the spectrophotometer The main power supply MPS is in a separate housing It does not contain any servicable parts inside In case it is defective it must not be opened but has to be exchanged as a complete assembly Removing the Main Power Supply 1 Turn off the spectrophotometer and disconnect the power cord Take the plastic and sheet metal front and rear covers off see Removing and Replacing Covers on page 109 2 To remove the fan see Removing the Fan Assembly on page 126 3 To remove the SPM board see Removing the SPM Board on page 120 4 Remove the middle rear foam block Figure 46 Removing the Middle Rear Foam Block 5 To remove the light pipe take the snap mechanism between two fingers and press it together to release the light pipe from the coupler on the main power supply Remove the light pipe with the power button middle rear foam 134 Maintenance and Repair Exchanging the Main Power Supply Figure 47 Removing the Light Pipe 6 Open the two screws from the rear panel of the instrument that hold the main power supply in place and sl
45. ents General This is a Safety Class I instrument provided with terminal for protective earthing and has been manufactured and tested according to international safety standards Operation Before applying power comply with the installation section Additionally the following must be observed Do not remove instrument covers when operating Before the instrument is switched on all protective earth terminals extension cords auto transformers and devices connected to it must be connected to a protective earth via a ground socket Any interruption of the protective earth grounding will cause a potential shock hazard that could result in serious personal injury Whenever it is likely that the protection has been impaired the instrument must be made inoperative and be secured against any intended operation Make sure that only fuses with the required rated current and of the specified type normal blow time delay and so on are used for replacement The use of repaired fuses and the short circuiting of fuseholders must be avoided Some adjustments described in the manual are made with power supplied to the instrument and protective covers removed Energy available at many points may if contacted result in personal injury Any adjustment maintenance and repair of the opened instrument under voltage should be avoided as much as possible When inevitable this should be carried out by a skilled person who is aware of the hazard i
46. eplace shutter Spectrograph disconnected or defective Connect or replace spectrograph Spectrophotometer lamp power supply SLS board disconnected or defective Connect or replace spectrophotometer lamp power power supply SLS board 84 Diagnostics and Troubleshooting General Troubleshooting Hints Measurement Results Indicate Excessive Noise Over The Whole Spectral Range Ensure that the lamps are turned on when making measurements Measurements taken with both lamps off exhibit excessive noise over the whole wavelength range In addition the self test only Agilent ChemStation software lamp intensity and stability diagnostics within the software can aid in diagnosing problems within the optical system which contribute to excessive noise Causes and solutions for excessive noise over the whole wavelength range are shown in Table 42 Table 42 Excessive Noise Over Whole Wavelength Range Possible Causes Action Light path is blocked Ensure that the light path is free and clear of all obstructions Cuvette or flow cell not installed correctly Check and correct cell installation Air bubble sticking on the quartz window of the flow cell Use cell cleaning fluid to passivate flow cell Source lens or spectrograph lenses dirty or fogged Clean lenses Shutter not functioning or partly blocking light Exchange shutter assembly Spectrophotometer data acqusition SDA board may be defective Exchange SDA board
47. er can result in low lamp intensity at the spectrograph Change cell to standard type Glass absorbs in the low UV region and causes high noise Make sure that your flow cells and cuvettes are made from quartz Solvent or buffer blocks light in a certain wavelength range If information is required in such a wavelength range a solvent or buffer that is transparent in that range should be used Fingerprints on cuvettes or flow cells typically absorb light in the UV range of the spectrum Clean your flow cells or cuvettes with a lens cleaning tissue Source lens or spectrograph lenses dirty or fogged Clean lenses Spectrophotometer lamp supply SLS board may be defective Exchange SLS board 86 Diagnostics and Troubleshooting General Troubleshooting Hints Spectrophotometer data acqusition SDA board may be defective Exchange SDA board Spectrograph electronics may be defective Exchange optical unit Table 43 Excessive Noise in Part of Spectrum continued Possible Causes Action 87 Diagnostics and Troubleshooting General Troubleshooting Hints Measurement Results Indicate Excessive Drift The selftest only Agilent ChemStation software lamp intensity and stability diagnostics within the software can aid in diagnosing problems within the optical system which contribute to excessive drift Causes and solutions for excessive drift are shown in Table 44 Table 44 Excessive Drift Possible Causes Acti
48. everal processing steps and hardware boards are required to form spectra from the intensity counts derived from the diode array Full spectra can be acquired processed and transmitted every 0 1 s continuously the only bottleneck being the PC speed The instrument has its own onboard real time clock and this allows the instrument to perform a series of time based accessory control actions and SPM spectrophotometer processor main board SLS spectrophoto meter lamp supply board SDA spectrophoto meter data acquisition board SSI spectrophotometer sipper interface switches LED spectrograph SCI spectrograph connector interface PDA photodiode array interfaces MPS spectrophotome ter main power shutter fan deuterium lamp tungsten lamp line power 30 Theory of Operation Electronics Overview measurements without control from the PC and buffer the data until the PC wants to take it SPM Spectrophotometer Processor Main Board The spectrophotometer processor main SPM board receives DC power from the main power supply MPS and distributes it to a number of other modules These include the spectrophotometer lamp supply SLS board spectrophotometer data acquisition SDA board and from there the spectrophotometer sipper interface SSI board and the spectrograph with the diode array The SPM board interfaces to the controller that is the computer and other devices such as pumps valves
49. ew M8 30 mm 0515 2520 12 Shutter assembly G1103 61904 13 1 MB memory for SPM board 1818 4721 13 4 MB memory for SPM board 1818 5784 14 Deuterium lamp 2140 0605 15 Optical unit including spectrograph optical bench and shutter G1103 69002 Part number may be subject to change Part number may be subject to change 140 Parts and Materials Exploded Views and Part List Figure 53 Spectrophotometer Lower Parts 17 19 34 21 23 29 31 36 35 18 32 30 28 33 20 22 24 26 141 Parts and Materials Exploded Views and Part List Table 50 Instrument Parts Breakdown Item Description Part Number 17 Power switch coupler 5041 8383 18 Fan assembly 3160 1103 19 PWR switch light pipe G1103 44602 20 Accessory slot cover 5001 3772 21 Power push button 5041 8381 22 GPIB standoff 0 255 inch not shown in Figure 53 0380 0643 Washer not shown in Figure 53 3050 0893 23 Screw M3 8 mm 0515 1105 24 Remote standoff not shown in Figure 53 1251 7788 25 27 34 36 Cable assembly kit G1103 68704 26 Screw set not shown in Figure 53 1251 0218 28 Screw M4 x 8 mm 0515 0910 Washer not shown in Figure 53 2190 0409 29 32 EPP foam parts kit containing foam front bottom foam rear bottom foam front top foam rear top foam rear middle are included and shown in Figure 52 G1103 68702 30 Main power supply 0950 2528 31
50. ffer ChemStation Software Intensity spectra with their variances are intermediately stored in the intensity run buffer if the acquisition of spectra is faster than the processing and data transfer to the ChemStation Handheld Controller Software The intensity run buffer is not used by the Agilent 8453E UV visible spectroscopy system because measuring time resolved intensity spectra is not supported by the handheld controller software Stray Light Correction Two intensity spectra are used for stray light correction one is measured with the stray light filter in the light path and one without Both spectra are combined to form one stray light corrected temperature corrected gain corrected dark current corrected intensity spectrum Absorbance Calculation To form an absorbance spectrum the stray light corrected intensity spectrum of the reference is divided by the stray light corrected intensity spectrum of the sample and the logarithm is calculated see Optical System Overview on page 19 Wavelength Axis Linearization Deuterium Line Data Wavelength Calibration Table Photodiodes are located on the array to give a sampling interval of nominal 0 9 nm over the whole wavelength range in the UV wavelength range In the visible and short wave near infrared wavelength ranges the sampling interval is slightly higher To correct for this optical non linearity and to convert from discrete diode distances to a continous linear scal
51. figuration settings are still being kept in non volatile random access memory NVRAM In this manner you can store more than one set of parameters for example for GPIB and RS232 using the same 8 bit configuration switch twice Forced Cold Start Settings Firmware update procedures may require this mode in case of firmware loading errors Unlike GPIB and RS232C settings using these settings does not force storage of this set of parameters in non volatile random access memory NVRAM Returning the switches 1 and 2 to other positions other than being both up will allow for normal operation CAUTION Forced cold start erases all methods and data stored in non volatile memory Exceptions are diagnose and repair log books which are save from being erased If you use the following switch settings and power the instrument up again a forced cold start has been completed To return to normal operation set switches back to your GPIB or RS 232 configuration settings Stay Resident Settings Firmware update procedures may require this mode in case of firmware loading errors Unlike GPIB and RS232C settings using these settings does not force storage of this set of parameters in non volatile random access memory NVRAM Returning the switches 1 and 2 to other positions other than being both up will allow for normal operation Table 54 Forced Cold Start Settings Mode Select 1 2 3 4 5 6 7 8 TEST BOOT 1 1 0 0 0 0
52. ftware of the handheld controller whenever low cycle times are set for data acquisition Absorbance Calculation and Averaging In case stray light correction is not applied this part of the firmware is used to calculate an absorbance spectrum the logarithm of the intensity spectrum of the reference is subtracted from the logarithm of the intensity spectrum of the sample Spectral averaging is used for noise reduction If an integration time of more than 100 ms is used multiple spectra dependent upon the selected integration time are measured Absorbance values of each wavelength are averaged to form one absorbance spectrum with variance for each wavelength Absorbance Run Buffer Absorbance spectra with their variances are intermediately stored here if the acquisition of spectra is faster than the processing and data communication to the ChemStation intensity values can also be stored for special purposes for example diagnostic reasons or handheld controller Intensity Averaging In case stray light correction is applied this part of the firmware is used Averaging of the intensity spectra is used for noise reduction If an integration time of more than 100 ms is used multiple spectra dependent upon the selected integration time are measured Intensity values of each wavelength are averaged to form one intensity spectrum with variance for each wavelength 47 Theory of Operation Firmware Description Intensity Run Bu
53. has failed to ignite the whole sequence is repeated If after the second attempt the deuterium lamp did not ignite an error message occurs Tungsten Lamp Voltage Control Voltage to the tungsten lamp is generated by the tungsten lamp voltage control circuit which is enabled by the processor resident on the SPM board This circuit provides a constant voltage of 6 V DC with currents between 0 7 0 9 A to light the tungsten lamp Diagnostic A D Converter The diagnostic A D converter senses currents and voltages of the deuterium and tungsten lamps and converts the analog signals into digital values The digital values are transferred via the control bus to the SPM board When values are outside of the normal range an appropriate error message is generated 41 Theory of Operation Spectrophotometer Lamp Supply SLS Board Safety Light Switches When the sheet metal lamp door is removed and the instrument is still on the safety light switches are activated and result in turn off of the deuterium and tungsten lamps The safety light switches provide shutdown in two different ways One is a direct line to the deuterium lamp filament and current control circuits as well as the tungsten lamp voltage control circuit The second is through the processor on the SPM board The different ways are used to provide maximum reliability and safety 42 Theory of Operation Spectrophotometer Interface SSI Board Spectrophotometer Interface
54. hassis of the instrument see Figure 38 2 Connect the shutter cable to the SPM board and the flat ribbon cable to the spectrograph see Figure 38 3 Replace the deuterium and tungsten lamps see Exchanging the Deuterium or Tungsten Lamp on page 96 4 Replace the upper rear and upper front foam blocks 5 If available replace any accessory board or MIO board plugged in from the rear side of the instrument 6 Replace the plastic and sheet metal front and rear covers Push the plastic front and rear covers down so that they locate on both sides see Removing and Replacing Covers on page 109 7 Reconnect line power and turn on the instrument Check that the spectrophotometer passes its self test this means that the green light on the front panel comes on and that you can do a blank measurement from your software 124 Maintenance and Repair Exchanging the Shutter Assembly Exchanging the Shutter Assembly The shutter assembly part number G1103 61904 is located in the top rear part of the spectrophotometer Removing the Shutter Assembly 1 Turn off the spectrophotometer and disconnect the power cord Take the plastic and sheet metal rear covers off see Removing and Replacing Covers on page 109 2 Remove any accessory board or MIO board that may be plugged in from the rear side of the instrument 3 Remove the upper rear foam block 4 Disconnect the shutter cable from the SPM board Open the screw that fi
55. he amplification factor in the signal conditioning electronics see Spectrophotometer Data Acquisition SDA Board on page 37 This process is used to adjust the signal level to the optimum range of the A D converter on the SDA board The DSP firmware uses the gain table to adjust the dark corrected intensity spectra Temperature Correction The quantum efficiency of the photodiode array depends on the temperature and is different for each wavelength The temperature dependency follows an e function over the wavelength scale for example it increases with the longer wavelengths To correct the intensity spectrum for temperature effects the temperature on the photodiode array is averaged over 5 10 s With the help of a table which stores correction coefficients for each wavelength correction factors for the current temperature are calculated and used for the temperature correction of the intensity spectrum Temperature Filter The temperature filter determines if temperature correction has to be applied If temperature changes of more than 0 004 K occur update is performed at a minimum interval of 5 10 s 46 Theory of Operation Firmware Description Apply Stray Light Correction By default a stray light correction is always used However for very fast measurements stray light correction can be turned off by the user interface of the ChemStation software The stray light correction is automatically turned off by the so
56. ide the main power supply out Figure 48 Removing the Main Power Supply Screws Replacing the Main Power Supply 1 Place the main power supply on the bottom foam in the rear part of the instrument and fix the two screws from the rear panel of the instrument that hold the main power supply in place see figure above 2 Attach the power button to the light pipe and slide the light pipe with the power button into the hole of the bottom foam part that the power button comes out of the hole at the base of the instrument Light pipe 135 Maintenance and Repair Exchanging the Main Power Supply Figure 49 Sliding in the Light Pipe 3 Take the snap mechanism between two fingers and press it together to get the light pipe end into the coupler on the main power supply Figure 50 Attaching Light Pipe to Main Power Supply 4 Replace the middle rear foam block Coupler 136 Maintenance and Repair Exchanging the Main Power Supply Figure 51 Replacing the Middle Rear Foam Block 5 To replace the SPM board see Replacing the SPM Board on page 121 6 To replace the fan see Replacing the Fan Assembly on page 126 7 Replace the plastic and sheet metal rear cover Push the plastic rear cover down so that it locates on both sides see Removing and Replacing Covers on page 109 8 Reconnect line power and turn on the instrument Check that the spectrophotometer passes its self test this means that the green light on th
57. iguration Switch The 8 bit configuration switch is located next to the GPIB connector Switch settings provide configuration parameters for GPIB address serial comunication protocol and instrument specific initialization procedures Figure 55 8 Bit Configuration Switch If you just want to change the GPIB address and need a detailed procedure refer to the Installing Your UV Visible Spectroscopy System handbook Default GPIB address is set to 25 equal to a binary setting of 0 0 0 1 1 0 0 1 where 0 means that the switch is down and 1 means that the switch is up the binary code of the address starts with the least significant bit at switch number 8 Switches 1 and 2 define which set of parameters for example for GPIB RS232 and so on will be changed Once the change has been completed the instrument must be powered up again in order to store the values in the non volatile memory In the non volatile random access memory NVRAM the parameters are kept independantly if you turn the instrument off and on again They will be kept until the same set of parameters is subsequently changed and power is 1 2 3 4 5 6 7 8 Table 53 8 Bit Configuration Switch Mode Select 1 2 3 4 5 6 7 8 GPIB 0 0 GPIB Address RS 232 0 1 Baudrate Data Bits Parity Reserved 1 0 Reserved TEST BOOT 1 1 RSVD SYS RSVD RSVD FC 147 Interfacing Setting the 8 Bit Configuration Switch reset All other previously stored con
58. iguration switch sets the instrument to resident mode Correct 8 bit configuration switch settings and turn instrument off then on again Because the wavelength recalibration is lost perform a wavelength recalibration with your software Spectrophotometer data acquisition SDA board disconnected or defective Connect or replace spectrophotometer data acquisition SDA board Main power supply MPS not connected to spectrophotometer processor main SPM board Connect main power supply MPS to spectrophotometer processor main SPM board Main power supply MPS or spectrophotometer processor main SPM board defective Replace main power supply MPS or spectrophotometer processor main SPM board Table 40 Power Switch LED Flickering Front Panel LED Off Shutter Does Not Click Possible Cause Action Main power supply MPS not connected to spectrophotometer processor main SPM board Connect main power supply MPS to spectrophotometer processor main SPM board 83 Diagnostics and Troubleshooting General Troubleshooting Hints Table 41 Front Panel LED Red Possible Cause Action An appropriate error message should occur in your software For explanation of error messages see Error Messages on page 71 Lamp door open or missing Close or replace door Lamp door sensor defective Replace spectrophotometer lamp power supply SLS board Shutter failed or disconnected Connect or r
59. in power supply 63 multicell transport 24 57 pump 51 52 53 remote 24 RS232 24 RS232C 58 shutter assembly 64 tungsten lamp 65 valve 54 construction and layout of instrument 26 control of interfaces 43 of MIO and accessory boards 43 conversion of raw data to absorbance 43 to absorbance spectra with variance 43 converter A D 31 correction factors for temperature 45 for dark current 35 45 for gain 45 for offset 35 162 Index for stray light 19 20 35 46 47 for temperature 45 covers 109 removing 109 113 replacing 111 114 CTS RTR hardware handshake 148 D damage to eyes 97 dark current correction 35 45 dark corrected intensity spectra 45 data bit settings 149 description of firmware 43 of instrument 22 detergent 95 deuterium lamp 19 47 64 96 connecting plugs 99 connector 64 current control 40 exchanging 94 96 filament control 40 fixing 99 ignition 40 light emission 40 removing 96 replacing 99 deuterium line data 47 diagnostic A D converter 40 functions 43 dimensions 11 diode array 21 disconnecting the lamp cables 97 door to access lamps 25 E EEPROM 38 eight bit configuration switch 146 eight channel peristaltic pump 53 electromagnetic interference 26 electronically programmable logic de vice EPLD 38 electronics overview 29 electrostatic discharge 108 emission of deuterium lamp 40 of radio frequencies 26 emission lines of deu
60. instrument 3 Remove the upper rear foam block 4 Disconnect the fan cable from the SPM board and remove the fan assembly Figure 40 Removing the Fan Assembly Replacing the Fan Assembly 1 Position the fan assembly in its recessment in the middle rear foam block and connect the fan cable to the SPM board 2 Replace the upper rear and upper front foam blocks 3 If available replace any accessory board or MIO board plugged in from the rear side of the instrument Fan assembly 127 Maintenance and Repair Exchanging the Fan Assembly 4 Replace the plastic and sheet metal rear cover Push the plastic rear cover down so that it locates on both sides see Removing and Replacing Covers on page 109 5 Reconnect line power and turn on the instrument Check that the spectrophotometer passes its self test this means that the green light on the front panel comes on and that you can do a blank measurement from your software 128 Maintenance and Repair Exchanging SDA Board Exchanging SDA Board The SDA board part number G1103 69504 is located below the optical unit of the spectrophotometer Removing the SDA Board 1 Turn off the spectrophotometer and disconnect the power cord Take the plastic and sheet metal front and rear covers off see Removing and Replacing Covers on page 109 2 To remove the optical unit see Removing the Optical Unit on page 122 3 Remove the lower front foam block 4 Disco
61. io Variations in the sample Check that the sample does not contain particulates that float in and out of the light beam filter if necessary shows signs of bubble formation though chemical reaction or degassing show signs of thermal or photochemical degradation One lamp switched off Check that both lamps are switched on if measurement over whole spectral range is required If spectra in the UV range only are being measured then deuterium lamp must be on If spectra in the Visible range only are being measured then tungsten lamp must be on Weak lamp Use diagnostics intensity test to check if lamp intensity is too low and change lamp if necessary 92 Diagnostics and Troubleshooting General Troubleshooting Hints Measured Values are Different to those of Another Instrument Causes and solutions for measured values being different to those of another instrument are shown in Table 48 Table 48 Measured Values are Different to those of Another Instrument Possible Causes Action Very low sample concentration Increase integration time to improve signal to noise ratio Variations in the sample Check that the sample does not contain particulates that float in and out of the light beam filter if necessary shows signs of bubble formation though chemical reaction or degassing show signs of thermal or photochemical degradation One lamp switched off Check that both lamps are switched
62. low pass filter for RFI radiated frequency interference improvement 39 Theory of Operation Spectrophotometer Lamp Supply SLS Board Spectrophotometer Lamp Supply SLS Board Figure 8 SLS Board 40 Theory of Operation Spectrophotometer Lamp Supply SLS Board Deuterium Lamp Filament Control During the ignition cycle two different voltage levels are applied to the filament of the deuterium lamp by the deuterium lamp filament control circuit This control circuit is enabled by the processor on the SPM board Deuterium Lamp Current Control The deuterium lamp current control circuit comprises two parts One generates an ignition pulse of 600 V DC for the lamp resulting in lamp ignition After the ignition process this voltage is disabled The second is a constant current source of 320 mA at an operating voltage between 50 and 105 V DC for stable operating conditions and light emission of the deuterium lamp The deuterium lamp current control circuit is supervised by the processor on the SPM board Igniting the Deuterium Lamp The deuterium lamp is heated with a voltage of 1 7 V DC for 1 s and afterwards a voltage 2 5 V DC for 9 s with currents between 2 10 A prior to ignition The deuterium lamp current control circuit provides an ignition pulse to the lamp resulting in lamp ignition The filament control circuit disables the filament voltage if the lamp has been successfully ignited If the deuterium lamp
63. ls with apertures of 2 mm or smaller always use flow cells and avoid removing it between measurements For multicell transport Never use a multicell transport as a single cell holder when apertured cuvettes are in use BLANK on position number 1 and SAMPLE on all other positions without doing a zero cells measurement Avoid removing and replacing the cells during a series of measurements Be sure that the clamp of the multicell 89075D is always closed then doing a measurement In general use only cells with blackened walls Table 45 Excessive Spikes or Glitches on Spectra continued Possible Causes Action 90 Diagnostics and Troubleshooting General Troubleshooting Hints Excessive Stray Light or Nonlinearity Causes and solutions for excessive stray light or nonlinearity are shown in Table 46 Table 46 Excessive Stray Light or Nonlinearity Possible Causes Action Non blackened apertured cells so called flourescence cells or plastic cells Use only cells with blackened walls Weak intensity in the UV region of the spectrum Check Deuterium lamp intensity 91 Diagnostics and Troubleshooting General Troubleshooting Hints Measurements are not Reproducible Causes and solutions for measurements not being reproducible are shown in Table 47 Table 47 Measurements are not Reproducible Possible Causes Action Very low sample concentration Increase integration time to improve signal to noise rat
64. m are switched on Receiver is any module relying on operation of others 7 READY H System is ready for next analysis Receiver is any sequence controller 8 STOP L Request to reach system ready state as soon as possible e g stop run abort or finish and stop injection Receiver is any module performing runtime controlled activities 9 START REQUEST L Request to start injection cycle e g by start key on any module Receiver is the autosampler Table 9 APG Remote Signal Distribution Pin Signal Function Table 10 Multicell Transport Connector Pin Function Pin Function 1 Status 9 Limit switch nc 2 OUT 4 10 Case 3 OUT 4 11 OUT 2 4 OUT 1 12 OUT 2 5 OUT 1 13 OUT 3 6 DGND 14 OUT 3 7 DGND 15 Shield 8 Limit switch no 58 Theory of Operation External Connectors CAN Connector The CAN is a high speed communication interface It is a two wire serial bus system supporting data communication with realtime requirements This CAN interface is used to connect the handheld controller of the Agilent 8453E UV visible spectroscopy system to the spectrophotometer RS232C Connector The RS232 is designed as DCE Data Communication Equipment with a 9 pin male SUB D type connector When controlling the spectrophotometer through the RS232 interface the connector needs to be activated and configured by the 8 bit configuration switch next to the GPIB connector For
65. meter 24 Theory of Operation Instrument Description Rear View All connections are made at the rear of the spectrophotometer see Figure 3 Figure 3 Rear View of Spectrophotometer The multicell connector allows you to connect the cable which comes from the multicell transport The GPIO general purpose input output connector allow you to control a sipper and autosampler or other accessories depending on the software you are using The remote connector may be used in combination with other analytical instruments from Agilent Technologies if you want to use features such as common shut down and so on The RS232C connector may be used to control the spectrophotometer from a computer through RS232 connection using appropriate software for future use This connector needs to be defined by the configuration switch module next to the GPIB connector The software needs the appropriate drivers to support this comunication which is intended for future use The RS232C port is used as printer interface to connect the printer using a serial parallel cable of the Agilent 8453E UV visible spectroscopy Line connector GPIB connector and switches Multicell transport connector GP IO connector RS 232 connector Remote connector Two CAN connectors MIO board slot Accessory board slot 25 Theory of Operation Instrument Description system The right CAN bus is used to connect the handheld cont
66. mp power supply SLS board 75 Diagnostics and Troubleshooting Error Messages Table 26 No Voltage At Deuterium Lamp Possible Causes Action Lamp is defective Replace deuterium lamp Electronics failed Replace spectrophotometer lamp power supply SLS board Table 27 No Current Through Tungsten Lamp Possible Causes Action If diagnostics in your software indicate that lamp voltage is available the lamp is defective Replace tungsten lamp Electronics failed Replace spectrophotometer lamp power supply SLS board Table 28 No Voltage At Tungsten Lamp Possible Causes Action Lamp is defective Replace tungsten lamp Electronics failed Replace spectrophotometer lamp power supply SLS board 76 Diagnostics and Troubleshooting Error Messages Table 29 Cooling Fan Defective Possible Causes Action Number of cycles per minute sensed at fan is too low Fan is defective Replace cooling fan Number of cycles per minute sensed at fan is too low Electronics failed Replace spectrophotometer processor main SPM board Table 30 Digital Signal Processor Error Possible Causes Action SIMM memory module on SPM board missing or in wrong position Make sure a module of minimum 1 MB is plugged into the position located towards the front panel of the instrument Communication error between the main processor and one of the digital signal processors located on the SPM or SDA board Cabl
67. nes are inactive To activate the GPIO lines as trigger lines type the following command on the command line of the Agilent ChemStation EnableGPIOButtons 1 This activation is not resident and has to be done every time the ChemStation is started or the Agilent 8453 is switched on again The general purpose cable G1103 61611 is recommended for connecting external hardware devices to the GPIO interface of the spectrophotometer Handheld Controller Software Measurements are activated on contact closure to ground pin 15 By default these trigger lines are active Pin 12 Trigger Stop and Pin 13 Trigger kinetics run are not supported by the software of the handheld controller The general purpose cable G1103 61611 is recommended for connecting external hardware devices to the GPIO interface of the spectrophotometer 61 Theory of Operation External Connectors 62 Internal Connections This section gives the definition of the connections inside the instrument including pin assignments of the connectors Only those connectors are described which may be important for troubleshooting 63 Theory of Operation Connector Definitions Connector Definitions Main Power Supply Connector The main power supply is connected to the spectrophotometer processor main SPM board by a cable that is fixed to the main power supply Fan Connector The fan is connected to the spectrophotometer processor main SPM board Table 14 P
68. nnect the three cables from the SDA board and remove the five scews that hold the board in place Figure 41 Removing the SDA Board SDA board 129 Maintenance and Repair Exchanging SDA Board Replacing the SDA Board 1 Position the SDA board on the bottom chassis of the instrument and fix the three scews that hold the board in place 2 Connect the three cables to the SDA board see Figure 41 3 On the side which is near the front of the instrument feed the broader cable through the hole in the lower front foam block and place the foam block on the chassis of the instrument Figure 42 Replacing SDA Board and Cables 4 To replace the optical unit see Replacing the Optical Unit on page 123 5 Replace the plastic and sheet metal rear cover Push the plastic rear cover down so that it locates on both sides see Removing and Replacing Covers on page 109 6 Reconnect line power and turn on the instrument Check that the spectrophotometer passes its self test this means that the green light on the front panel comes on and that you can do a blank measurement from your software Hole in foam block Lower front foam block SDA board 130 Maintenance and Repair Exchanging SLS Board Exchanging SLS Board The SLS board part number G1103 69502 is located below the SPM board in the rear part of the spectrophotometer Removing the SLS Board 1 Turn off the spectrophotometer and disconnect the power cord Take
69. ns performance 12 physical 11 spectra and signal processor SSP 35 spectral acquisition 46 averaging 46 spectrograph 20 30 connector interface board SCI 38 lens 19 21 lens cleaning 105 slit 19 spectrophotometer data acquisition board SDA 30 front view 22 industrial design 26 interface board SSI 42 lamp supply board SLS 30 processor main board SPM 30 rear view 24 sipper interface board SSI 30 31 38 109 116 SPM board 30 block diagram 34 exchanging 120 removing 120 removing connectors and screws 121 replacing 121 SSI board 30 31 38 42 109 116 block diagram 42 stability 13 standard push button 23 standard TTL levels 50 standards 14 for photometric accuracy 14 for wavelength accuracy 14 NIST 2034 12 14 NIST 930e 12 14 potassium dichromate 12 status indicator 22 stay resident settings 147 stop push button 23 stray light 12 22 stray light correction 19 20 30 35 46 47 filter 47 subtract dark current 45 surface of source lens 102 103 system memory 35 T temperature compensation of photodiode 35 correction 45 effects 45 filter 45 operating 11 sensor 33 TEST BOOT mode select 146 time for shortest scan 13 for typical scan 13 until next scan 13 tungsten lamp 19 96 connecting plugs 99 connector 65 exchanging 94 96 fixing 99 removing 96 replacing 99 voltage control 40 typical scan time 13 U upgrading internal memory
70. nvolved Do not attempt internal service or adjustment unless another person capable of 155 Safety Information rendering first aid and resuscitation is present Do not replace components with power cable connected Do not operate the instrument in the presence of flammable gases or fumes Operation of any electrical instrument in such an environment constitutes a definite safety hazard Do not install substitute parts or make any unauthorized modification to the instrument Capacitors inside the instrument may still be charged even though the instrument has been disconnected from its source of supply Dangerous voltages capable of causing serious personal injury are present in this instrument Use extreme caution when handling testing and adjusting Safety Symbols WARNING A warning alerts you to situations that could cause physical injury or damage to the equipment Do not proceed beyond a warning until you have fully understood and met the indicated conditions CAUTION A caution alerts you to situations that could cause a possible loss of data Do not proceed beyond a caution until you have fully understood and met the indicated conditions Table 61 Safety Symbols used on Instruments and in Manuals Symbol Description The apparatus is marked with this symbol when the user should refer to the instruction manual in order to protect the apparatus against damage Indicates dangerous voltages Indicates a protected g
71. of the spectrophotometer processor system Because in this case there is no communication with the computer there will be no error message The online help system and Chapter 3 Diagnostics and Troubleshooting give more information about troubleshooting NOTE When using an Agilent 8453E UV vis spectroscopy system you will only have access to the online help of the handheld controller when there is no power loss at the CAN interface of the Agilent 8453 spectrophotometer The four measure push buttons on the front panel cause the following actions to be performed and the resulting data being sent to the computer BLANK the instrument takes a blank measurement This comprises a reference measurement that is used in all subsequent sample measurements until a new blank measurement is taken Following the reference measurement the baseline spectrum is measured and displayed on the PC SAMPLE the instrument takes a sample measurement or starts a series of measurements This depends on the parameters set in your software STANDARD the instrument takes a measurement of a standard Additional information such as concentration and so on have to be entered in the operating software STOP the instrument and or software aborts any ongoing activity and returns to a to ready state The stop button is not supported when the handheld controller of the Agilent 8453E UV vis spectroscopy system is used to control the spectrophoto
72. olution is available from U S Department of Commerce National Institute of Standards and Technology Standard Reference Materials Program Bldg 202 Room 204 Gaithersburg MD 20899 USA Tel 301 975 6776 Photometric Accuracy The NIST 930e standard is available from NIST see above address Other Standards All other standards can be prepared using the appropriate material recommended in the EP or ASTM procedures Agilent Technologies Standards Kit All liquid standards required by the EP or ASTM are available in snap open ampules from Agilent Technologies These standards are easy to handle inexpensive and traceable The OQ PV chemical standards kit I order number 5063 6503 contains potassium dichromate sodium nitrite sodium iodide and toluene in hexane The OQ PV chemical standards kit II order number 5063 6521 contains holmium oxide in perchloric acid 2 2 Theory of Operation An overview of the instrument the theory of operation and control as well as external communication and internal connections 16 Theory of Operation This chapter has four sections Instrument Overview on page 18 Theory of Operation and Control on page 28 External Communication on page 50 and Internal Connections on page 62 17 Theory of Operation 18 Instrument Overview This section gives an overview of the optical system and explains the instrument front and back panel I
73. on Variations in temperature Ensure that the environment in which the spectrophotometer is being used is stable The photodiode array temperature may be monitored from within the software to verify PDA temperature stability Sample degrades with time and or exposure to light Use the spectrophotometer without sample If the problem is found to be sample related i e sample exposure to light limit the amount of light by the environment and or shorten the integration time to limit the amount of light during the measurement or use filter wheel to cut out the energetic low UV range Floating particles in the cell Filter sample before measurement Deuterium lamp may burn unstable Exchange lamp Tungsten lamp may burn unstable Exchange lamp Spectrophotometer lamp supply SLS board may supply unstable power Exchange SLS board Spectrophotometer data acqusition SDA board may be defective Exchange SDA board Main power supply MPS may supply unstable power Exchange MPS Spectrograph electronics may be defective Exchange optical unit 88 Diagnostics and Troubleshooting General Troubleshooting Hints Excessive Spikes or Glitches on Spectra Causes and solutions for excessive spikes or glitches on spectra are shown in Table 45 Table 45 Excessive Spikes or Glitches on Spectra Possible Causes Action BLANK on air SAMPLE on cuvette Measure Blank on the same solvent as used for the sample Dramatic
74. on point Installation and onsite warranty services are available only in Agilent service travel areas and only in the country of initial purchase unless buyer pays Agilent international prices for the product and services Warranties requiring return to Agilent are not limited to the country of purchase For installation and warranty services outside of Agilent s service travel area Agilent will provide a quotation for the applicable additional services If products eligible for installation and onsite warranty services are moved from the initial installation point the warranty will remain in effect only if the customer purchases additional inspection or installation services at the new site The foregoing warranty shall not apply to defects resulting from 1 improper or inadequate maintenance adjustment calibration or operation by buyer 2 buyer supplied software hardware interfacing or consumables 3 unauthorized modification or misuse 152 Warranty Statement 4 operation outside of the environmental and electrical specifications for the product 5 improper site preparation and maintenance or 6 customer induced contamination or leaks THE WARRANTY SET FORTH IS EXCLUSIVE AND NO OTHER WARRANTY WHETHER WRITTEN OR ORAL IS EXPRESSED OR IMPLIED AGILENT SPECIFICALLY DISCLAIMS THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE Limitation of Remedies and Liability THE REMEDIES PR
75. ons are measured after a minimum 1 hour from cold start or from lamp turn on with no cell or filter unless specified see Table 2 Cold start in this context means that the spectrophotometer had been stored for some hours at room temperature Table 2 Performance Specifications Type Specification Comments Wavelength range 190 1100 nm Slit width 1 nm Resolution gt 1 6 Toluene in hexane ratio of absorbances at 269 and 266 nm Stray light lt 1 0 At 200 nm solution of 1 2 KCl blank scan on air 5 s integration time EP method lt 0 05 At 220 nm solution of 10 g l NaI blank scan on air 5 s integration time ASTM method lt 0 03 At 340 nm solution of 50 g l NaNO2 blank scan on air 5 s integration time ASTM method Wavelength accuracy lt 0 5 nm NIST 2034 standard using transmittance peak minima wavelength in NIST certificate are interpolated for 1 5 nm bandwidth from the values given for 2 nm and 1 nm bandwidth uncertainty of standard from NIST certificate typically 0 1 nm is added to the specification 99 point spline function is used 0 5 s integration time Wavelength reproducibility lt 0 02 nm Ten consecutive scans with NIST 2034 standard 0 5 s integration time Photometric accuracy lt 0 005 AU NIST 930e standard at 1 AU at 440 0 465 0 546 1 590 0 and 635 0 nm the expanded uncertainty from NIST certificate is added to the specification 0 5 s integration time
76. ont Cover 3 Remove the keyboard cable from the spectrophotometer sipper interface SSI board located inside the plastic front cover 110 Maintenance and Repair Removing and Replacing Covers Figure 22 Removing the Keyboard Cable 4 Remove the cuvette holder and sample pan from the sample compartment Figure 23 Removing Cuvette Holder and Sample Pan 5 To remove the sheet metal front cover untighten the screw near the top of the cover using a Pozidriv screwdriver 111 Maintenance and Repair Removing and Replacing Covers Figure 24 Removing the Sheet Metal Front Cover 6 Slide the sheet metal front cover towards the rear of the instrument and lift it up Replacing the Front Covers 1 Slide in metal front cover so that it locates on the bottom first Slide it in further so that it locates on top Figure 25 Replacing the Metal Front Cover 2 Tighten the screw near the top of the cover using a Pozidriv screwdriver 3 Replace the sample pan and cuvette holder in the sample compartment 112 Maintenance and Repair Removing and Replacing Covers Figure 26 Replacing the Sample Pan and Cuvette Holder 4 Place the plastic front cover on top of the sheet metal cover so that you are able to connect the cable to the keyboard SSI board Figure 27 Connecting the Keyboard Cable 5 Push the plastic cover down so that it locates on both sides 6 Reconnect line power and turn on the instrument Check that the spectroph
77. ook This handbook is intended for the technical reader who needs background information about the Agilent 8453 spectrophotometer and potential repairs The handbook contains specifications of the spectrophotometer as well as descriptions of front and back panels for example where to connect accessories Electronics are explained at block diagram level There is a detailed section about troubleshooting to help find a defective subassembly such as an electronic board in case the spectrophotometer does not operate any more Part replacement procedures as well as an exploded view with part numbers are given for ordering and replacing assemblies For information about installation of the system including the spectrophotometer computer and accessories see the Installing Your UV Visible Spectroscopy System handbook Use Chapter 1 Specifications to check the specifications of the spectrophotometer Use Chapter 2 Theory of Operation if you want an overview of the optics front and rear panel functions or if you need explainations about the electronics or pin assignment of cables Use Chapter 3 Diagnostics and Troubleshooting to find explainations of status and error messages and a logical approach to troubleshooting Use Chapter 4 Maintenance and Repair for exchanging parts such as lamps and electronical or mechanical items and cleaning lenses Use Chapter 5 Parts and Materials to locate parts and find out thei
78. otometer passes its self test this means that the green light on the front panel comes on and that you can do a blank measurement from your software SPM board 122 Maintenance and Repair Exchanging the Optical Unit Exchanging the Optical Unit The optical unit part number G1103 69002 includes spectrograph optics bench shutter and lamp housing and it is exchanged as one item Removing the Optical Unit 1 Turn off the spectrophotometer and disconnect the power cord Take the plastic and sheet metal rear and front covers off see Removing and Replacing Covers on page 109 2 Remove any accessory board or MIO board that may be plugged in from the rear side of the instrument 3 Remove the upper rear and upper front foam blocks 4 Remove the Deuterium and Tungsten lamps see Exchanging the Deuterium or Tungsten Lamp on page 96 5 Disconnect the shutter cable from the SPM board and the flat ribbon cable from the spectrograph Figure 38 Removing the Optical Unit 6 Remove the three hexagonal screws that hold the optical unit on the chassis of the instrument Take the screws out to be able to lift up the optical unit 7 Lift the optical unit out of the instrument and place it on the bench 123 Maintenance and Repair Exchanging the Optical Unit Replacing the Optical Unit 1 Place the optical unit onto the bottom chassis of the instrument Tighten the three hexagonal screws that hold the optical unit on the c
79. otometer passes its self test this means that the green light on the front panel comes on and that you can do a blank measurement from your software and the keyboard of the spectrophotometer 113 Maintenance and Repair Removing and Replacing Covers Removing the Rear Covers 1 Turn off the spectrophotometer and disconnect the power cord 2 To remove the plastic rear cover hold the plastic cover on the lower edge with two hands from the left and right of the instrument Pull the lower edges of the cover in opposite directions and simultaneously lift up Figure 28 Removing the Plastic Rear Cover 3 Remove the cuvette holder and sample pan from the sample compartment Figure 29 Removing Cuvette Holder and Sample Pan 4 To remove the sheet metal rear cover untighten the screw near the top of the cover using a Pozidriv screwdriver 114 Maintenance and Repair Removing and Replacing Covers Figure 30 Removing the Sheet Metal Rear Cover 5 Slide the sheet metal rear cover towards the front of the instrument and lift it up Replacing the Rear Cover 1 Slide in metal rear cover so that it locates on the bottom first Slide it in further so that it locates on top Figure 31 Replacing the Metal Rear Cover 2 Tighten the screw near the top of the cover using a Pozidriv screwdriver 3 Replace the sample pan and cuvette holder in the sample compartment 115 Maintenance and Repair Removing and Replacing Covers Figure 32
80. ower Supply Cable to SPM Board Pin Function Pin Function 1 Power failure 7 8 24 V 2 Analog ground AGND 9 10 36 V not used 3 15 V 11 Digital ground DGND 4 15 V 12 5 V 5 6 Power ground PGND Table 15 Fan Connector Pin Function 1 Fan Power 2 Fan Rotation Sensor 3 GND 64 Theory of Operation Connector Definitions Shutter Assembly Connector The shutter assembly is connected to the spectrophotometer processor main SPM board Deuterium Lamp Connector The deuterium lamp is connected to the spectrograph lamp supply SLS board Table 16 Shutter Assembly Connector Pin Function 1 2 Coil Filter 3 4 Coil Dark 5 6 GND 7 8 Coil Common 9 10 GND Table 17 Deuterium Lamp Connector Pin Function 1 Heater 2 Cathode 3 Anode 65 Theory of Operation Connector Definitions Tungsten Lamp Connector The tungsten lamp is connected to the spectrograph lamp supply SLS board Table 18 Tungsten Lamp Connector Pin Function 1 Vis Sense 2 Vis Lamp 3 Vis Lamp 4 Vis Sense 66 Theory of Operation Connector Definitions 3 3 Diagnostics and Troubleshooting Explainations of status and error messages and a logical approach to troubleshooting 68 Diagnostics and Troubleshooting For different stages of troubleshooting the startup test of the spectrophotometer instrument self test and various diagnostic tests are
81. power or the main power supply MPS is defective Refer to Table 20 through Table 34 for detailed troubleshooting information Red front panel LED The spectrophotometer does not pass one of the self tests which are run when the spectrophotometer is turned on or an error occurred during operation Most of the causes have to do with ignition of lamps open lamp door multicell transport problems or spectrophotometer hardware problems If your controller is running personal computer or handheld controller and connected to the spectrophotometer you may get an error message This message will tell you more about the cause of the error For details about error messages see Table 20 through Table 34 or the help system Red blinking front panel LED Error condition of the spectrophotometer processor system Because in this case there is no communication with the computer there will be no error message Turn the instrument off and on again If the error appears again possible causes are shown in Table 19 70 Diagnostics and Troubleshooting Front Panel Status and Power Switch LEDs Table 19 Error Condition of Spectrophotometer Processor System Possible Causes Action Spectrophotometer main processor SPM board defective Exchange SPM board Spectrophotometer data acquisition SDA board defective Exchange SDA board 71 Diagnostics and Troubleshooting Error Messages Error Messages Error messages are a series of tex
82. r part numbers Use Chapter 6 Interfacing to set the 8 bit switch for RS232 comunication and to reset the spectrophotometer in case of problems when loading a new firmware Use the Installing Your UV Visible Spectroscopy System handbook for information about GPIB settings Contents 5 1 Specifications Specifications of the Agilent 8453 UV visible spectrophotometer 9 Physical Specifications 11 Performance Specifications 12 Source of Standards 14 2 Theory of Operation An overview of the instrument the theory of operation and con trol as well as external communication and internal connections 15 Instrument Overview 18 Optical System Overview 19 Instrument Description 22 Instrument Layout and Construction 26 Theory of Operation and Control 28 Electronics Overview 29 The Main Power Supply Assembly 32 Spectrophotometer Processor Main SPM Board 34 Spectrophotometer Data Acquisition SDA Board 37 Spectrophotometer Lamp Supply SLS Board 39 Spectrophotometer Interface SSI Board 42 Firmware Description 43 External Communication 50 External Cables 51 6 Contents External Connectors 56 Internal Connections 62 Connector Definitions 63 3 Diagnostics and Troubleshooting Explainations of status and error messages and a logical ap proach to troubleshooting 67 Front Panel Status and Power Switch LEDs 69 Error Messages 71 General Troubleshooting Hints 80 4 Maintenance and Rep
83. rd SDA board 35 Theory of Operation Spectrophotometer Processor Main SPM Board Main Microprocessor The main microprocessor exchanges data with the ASIC through the core bus as well as with the memory consisting of the battery backed up non volatile random access memory NVRAM the system memory and the program memory The program memory includes the firmware which can be updated by a download procedure from the computer The battery for the NVRAM and the real time clock is designed to last for more than 25 years under normal operating conditions Control lines provide communication to the SLS board which in turn controls the deuterium and tungsten lamps The main microprocessor comunicates to the SSP spectra and signal processor through a parallel bus ASIC Application Specific Integrated Circuit The 304 pin application specific integrated circuit ASIC provides interfacing to external devices through drivers including GPIB CAN APG Remote and GPIO It is also connected to the four control LEDs located near the connectors on the SPM board and the 8 bit configuration switch which is used to configure the address for the GPIB communication baud rate for RS232 transfer and so on For switch settings refer to the Installing Your UV Visible Spectroscopy System handbook In addition it controls the shutter and cooling fan through the PWM pulse width modulation driver Operation of the cooling fan is sensed by the micropro
84. roller of the Agilent 8453E UV visible spectroscopy system to the spectrophotometer The GPIB connector is used to connect the spectrophotometer with a computer The 8 bit configuration switch module next to the GPIB connector determines the GPIB address of your spectrophotometer The switches are preset to a default address recognized by the operating software from Agilent Technologies The GPIB port is not used when the handheld controller of the Agilent 8453E UV visible spectroscopy system is connected to the spectrophotometer However the 8 bit configuration switch of the port must be set for GPIB communication The MIO board slot is reserved for a LAN interface board The accessory board slot is reserved for future use The power input socket does not have a voltage selector because the power supply has wide ranging capability for more information see Chapter 1 Specifications There are no externally accessible fuses because automatic electronic fuses are implementeded in the power supply The security lever at the power input socket prevents that the spectrophotometer cover is taken off when line power is still connected Side of the Instrument On the right side of the instrument there is a door for exchanging the lamps Behind this plastic door there is another sheet metal door Two independant safety light switches are implemented They automatically turn off the lamps when the sheet metal door is opened
85. ronment An indication for dirty lenses is when after exchanging the lamps the intensity test executed by your operating software still falls below the specified level Cleaning the Source Lens The source lens is a lens system which has one optical surface accessible from inside the lamp housing The other optical surface is behind the shutter thus accessible from the sample compartment Cleaning the Source Lens from the Sample Compartment Side 1 Turn off the spectrophotometer and disconnect the power cord 2 Remove any cuvette holder from the sample compartment 3 To have better access you may want to take the plastic and metal rear covers off see Removing and Replacing Covers on page 109 4 Dampen a lint free surgical cotton swab with reagent grade isopropanol isopropyl alcohol and gently swab the surface of the source lens Repeat several times with clean swabs and alcohol each time 104 Maintenance and Repair Cleaning the Lenses Figure 18 Cleaning the Source Lens from the Sample Compartment Side 5 Use a canister of compressed oil free air like those used to clean photographic lenses to further clean the source lens If you do not have a compressed air canister you can use a photographic lens cleaning brush 6 If you have taken the covers off replace them 7 Replace the cuvette holder Reconnect line power and turn on the instrument Check that the spectrophotometer passes its self test this means that
86. round terminal Eye damage may result from directly viewing light produced by deuterium lamps used in detectors and spectrophotometers Always turn off the deuterium lamp before opening the lamp door on the instrument 156 Solvent Information Solvent Information Observe the following recommendations on the use of solvents Flow Cells Avoid the use of alkaline solutions pH gt 9 5 which can attack quartz and thus impair the optical properties of flow cells Solvents Always filter solvents small particles can permanently block capillaries Avoid the use of the following steel corrosive solvents Solutions of alkali halides and their respective acids for example lithium iodide potassium chloride and so on High concentrations of inorganic acids like nitric acid sulfuric acid especially at higher temperatures replace if your analysis method allows by phosphoric acid or phosphate buffer which are less corrosive against stainless steel Halogenated solvents or mixtures which form radicals and or acids for example 2CHCl3 O2 2COCl2 2HCl This reaction in which stainless steel probably acts as a catalyst occurs quickly with dried chloroform if the drying process removes the stabilizing alcohol Analysis grade ethers which can contain peroxides for example THF dioxane di isopropylether such ethers should be filtered through dry aluminium oxide which adsorbs the peroxides
87. ry 35 pulse width modulation driver PWM 35 pump connector 51 52 53 push buttons 23 blank 23 sample 23 standar 23 stop 23 Q quantum efficiency of the photodiode array 45 quartz envelope 98 R radiated frequency interference RFI 38 radiation source 19 radio frequency emissions 26 random access memory non volatile 35 range of wavelengths 12 raw data 45 conversion to absorbance 43 flow from photodiode array 43 real pass band function 48 real time clock 35 rear cover removing 113 replacing 114 rear view of spectrophptometer 24 recalibration 48 remote connector 24 removing accessory boards 118 120 connectors and screws from SPM board 121 covers 109 key pad 116 keyboard 116 MIO board 118 120 SIMM memory modules 118 the deuterium lamp 96 the fan assembly 126 the front covers 109 the keyboard cable 109 the light pipe 134 the main power supply 133 the middle rear foam block 130 the optical unit 122 the rear cover 113 the sample pan 110 113 the SDA board 128 the shutter assembly 101 124 the SLS board 130 the SPM board 120 the tungsten lamp 96 repair procedures 108 repairing the instrument 108 replacing 109 covers 109 key pad 116 keyboard 116 SIMM memory modules 119 the deuterium lamp 99 the fan assembly 126 the front covers 111 the main power supply 134 the middle rear foam block 131 the optical unit 123 the rear cover 114 the sample pan 111
88. s on and that you can do a blank measurement from your software Cleaning the Spectrograph Lens 1 Turn off the spectrophotometer and disconnect the power cord 2 Remove any cuvette holder from the sample compartment 3 To have better access you may want to take the plastic and metal front covers off see Removing and Replacing Covers on page 109 4 Dampen a lint free surgical cotton swab with reagent grade isopropanol isopropyl alcohol and gently swab the surface of the spectrograph lens Repeat several times with clean swabs and alcohol each time Source lens 106 Maintenance and Repair Cleaning the Lenses Figure 20 Cleaning the Spectrograph Lens 5 Use a canister of compressed oil free air like those used to clean photographic lenses to further clean the spectrograph lens If you do not have a compressed air canister you can use a photographic lens cleaning brush 6 If you have taken the covers off replace them Replace the cell holder in the sample compartment 7 Reconnect line power and turn on the instrument Check that the spectrophotometer passes its self test this means that the green light on the front panel comes on and that you can do a blank measurement from your software Spectrograph lens 107 Maintenance and Repair Cleaning the Lenses 108 Repair Procedures This section gives detailed descriptions of procedures to repair the instrument Always disconnect the instrument from line power
89. sa Agilent 8453 UV visible Spectroscopy System Service Manual Agilent Technologies Deutschland GmbH Hewlett Packard Strasse 8 76337 Waldbronn Germany Copyright Agilent Technologies 2000 All rights reserved Reproduction adaption or translation without prior written permission is prohibited except as allowed under the copyright laws Part No G1103 90004 Edition 02 00 Printed in Germany Warranty The information contained in this document is subject to change without notice Agilent Technologies makes no warranty of any kind with regard to this material including but not limited to the implied warranties or merchantability and fitness for a particular purpose Agilent Technologies shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing performance or use of this material WARNING For details of safety see Safety Information on page 154 Warning Symbols Used In This Book The apparatus is marked with this symbol when the user should refer to the instruction manual in order to protect the apparatus against damage Eye damage may result from directly viewing the light produced by the deuterium lamp used in this product Always turn off the deuterium lamp before opening the metal lamp door on the side of the instrument Service Manual Agilent 8453 UV visible Spectroscopy System 4 In This B
90. sampler a multicell transport a Peltier temperature control accessory and valve unit and valve pump controller The spectrophotometer can be either controlled from HP and non HP personal computers equipped with Agilent ChemStation software for UV visible spectroscopy personal computers used should be certified by UL1950 or from the dedicated handheld controller that comes with the Agilent 8453E UV vis spectroscopy system 11 Specifications Physical Specifications Physical Specifications WARNING If you use the spectrophotometer at environmental temperatures higher than 50 C 122 F the backplane may get hot Table 1 Physical Specifications Type Specification Comments Dimensions 34 4 cm 13 5 inches wide 56 0 cm 22 0 inches deep 18 5 cm 7 3 inches high Weight 16 5 kg 36 3 lbs Line voltage 90 264 V AC Wide ranging capability Line frequency 47 63 Hz Power consumption 220 VA Maximum Ambient operating temperature 0 55 C 32 131 F See WARNING on page 11 Ambient non operating temperature 40 70 C 4 158 F Humidity lt 95 at 25 40 C 77 104 F Non condensing Operating altitude Up to 2000 m 6 500 ft Non operating altitude Up to 4600 m 14 950 ft For storing the instrument Safety standards IEC CSA UL Installation Category II Polution Degree 2 12 Specifications Performance Specifications Performance Specifications Performance specificati
91. stem are correct Loss of communication This may occur because of exceptional power line conditions spikes or drop outs Check that the power supply to the instrument is good 80 Diagnostics and Troubleshooting General Troubleshooting Hints General Troubleshooting Hints Instrument problems may not always result in error messages Proper instrument performance is determined by the quality of the results Even if your instrument turns on passes its self tests and operates without generating error messages it may not be functioning perfectly The results of measurements can provide hints for troubleshooting if measurement results are less than optimal Typical power on sequence failed During a typical power on sequence the following events occur the power switch LED will ignite and remain on the front panel LED will turn yellow then flash red green and stay yellow the fan speed will decrease the shutter will close if you listen carefully you may here a click the front panel LED will turn green The green front panel LED indicates successful completion of the self test sequence NOTE Your software may be set so that lamp ignition does not automatically occur during power on In this case use your software to ignite the deuterium and tungsten lamps 81 Diagnostics and Troubleshooting General Troubleshooting Hints If any or all of the above listed actions do not occur there may be a
92. system 6 Use a Pozidriv screwdriver to open the two screws that hold each lamp and take it out holding it at the lamp ring 7 Place the lamp s on a clean optical tissue or another place where it cannot collect dust CAUTION Never touch the quartz envelope of the deuterium lamp with your fingers Fingerprints absorb UV light and may be burnt in thus reducing lifetime of the lamp If you have accidentally touched it use isopropanol to wipe the fingerprint off Deuterium lamp Tungsten lamp 99 Maintenance and Repair Exchanging the Deuterium or Tungsten Lamp Replacing the Deuterium or Tungsten Lamp 1 Holding the lamp s at the lamp ring carefully slide it into the lamp housing and avoid touching the quartz envelope of the deuterium lamp see CAUTION on page 98 The tungsten lamp ring has a flat part which has to show towards the deuterium lamp location The deuterium lamp has a recessment for a location pin on the lamp housing Figure 15 Replacing the Lamps 2 Take a Pozidriv screwdriver and fix the two screws which fix each lamp 3 Connect the plug s of the lamp s to the electronic board see Figure 14 There is only one way to get the plug s in 4 Slide in the metal door and close so that it is locked Close the plastic door Figure 16 Sliding In and Closing the Metal Door and Closing Recessment at deuterium lamp Flat part at tungsten lamp 100 Maintenance and Repair Exchanging the Deuterium or Tungs
93. t 2 Under Set Gains in the Measure menu select water or air Bubble in flow cell absorbing during blank Use cell cleaning fluid to prevent air bubbles sticking on the window surface of the flow cell Floating particle s in cell Clean cell or wait untill particle s have settled Variation in sample absorbance during the measurement process due to chemical or physical processes Select a shorter integration time Fluorescent sample Use fixed gain settings in your advanced software for the Agilent ChemStation This feature is not implemented in the software of the handheld controller Electronics failed Replace the spectrophotometer data acquisition SDA board Replace optical unit Bad blank Repeat blank measurement 74 Diagnostics and Troubleshooting Error Messages Table 23 No Filament Current Through Deuterium Lamp Possible Causes Action Lamp is defective Replace deuterium lamp Electronics failed Replace spectrophotometer lamp power supply SLS board Table 24 Deuterium Lamp Ignition Failed Possible Causes Action Lamp is defective Replace deuterium lamp Electronics failed Replace spectrophotometer lamp power supply SLS board Table 25 No Current Through Deuterium Lamp Possible Causes Action If diagnostics in your software indicate that lamp voltage is available the lamp is defective Replace deuterium lamp Electronics failed Replace spectrophotometer la
94. t also explains the layout and construction of the instrument including the electronic and mechanical assemblies inside the instrument 19 Theory of Operation Optical System Overview Optical System Overview Optical System The optical system of the spectrophotometer is shown in Figure 1 Its radiation source is a combination of a deuterium discharge lamp for the ultraviolet UV wavelength range and a tungsten lamp for the visible VIS and short wave near infrared SWNIR wavelength range The image of the filament of the tungsten lamp is focused on the discharge aperture of the deuterium lamp by means of a special rear access lamp design which allows both light sources to be optically combined and share a common axis to the source lens The source lens forms a single collimated beam of light The beam passes through the shutter stray light correction filter area then through the sample to the spectrograph lens and slit In the spectrograph light is dispersed onto the diode array by a holographic grating This allows simultaneous access to all wavelength information The result is a fundamental increase in the rate at which spectra can be acquired Figure 1 Optical System of Spectrophotometer Lamps The light source for the UV wavelength range is a deuterium lamp with a shine through aperture As a result of plasma discharge in a low pressure deuterium gas the lamp emits light over the 190 nm to approximately 800 nm wavelength range
95. t messages which appear in your software These messages notify you that either the spectrophotometer is not functioning correctly or in case you are using your own customized programs that you have made a mistake in the commands which you have given to the spectrophotometer The following is an overview of the error messages For suggestions regarding causes and courses of action see Table 20 through Table 34 Multicell Transport Home Position Not Found No Filament Current On Deuterium Lamp Deuterium Lamp Ignition Failed No Current Sensed On Deuterium Lamp No Voltage Sensed On Deuterium Lamp No Current Sensed On Tungsten Lamp No Voltage Sensed On Tungsten Lamp Cooling Fan Defective Lamp Door Open Lamps are switched off Digital Signal Processor Error Wavelength Calibration Data Rejected Excessive Dark Current Detected On Photodiodes Raw Data Buffer Overflow Power Fail Most of these error messages are stored with the Agilent 8453 spectrophotometer logbook and can be recalled through the operating software Table 20 through Table 34 show the error messages with their meanings The tables explain the instrumental conditions required to generate the message and potential causes which lead to generation of the message There is a list of suggested actions to correct the instrument state when necessary 72 Diagnostics and Troubleshooting Error Messages
96. ten Lamp 5 Reconnect line power and turn on the instrument Check that the spectrophotometer passes its self test this means that the green light on the front panel comes on and that you can do a blank measurement from your software 101 Maintenance and Repair Cleaning the Stray Light Filter Cleaning the Stray Light Filter Cleaning the stray light filter is recommended at one yearly intervals or more frequently when you operate the spectrophotometer in particularly dirty environment An indication for a dirty stray light filter is when after exchanging the lamps the intensity test executed by your operating software still falls below the specified level one of the stray light tests fails the photometric accuracy test fails Removing the Shutter Assembly 1 Turn off the spectrophotometer and disconnect the power cord Take the plastic and sheet metal rear covers off see Removing and Replacing Covers on page 109 2 Remove any accessory board or MIO board that may be plugged in from the rear side of the instrument 3 Remove the upper rear foam block 4 Disconnect the shutter cable from the SPM board Open the screw that fixes the shutter assembly to the optical unit and remove the shutter assembly Figure 17 Removing the Shutter Assembly Shutter assembly Shutter screw Stray light filter 102 Maintenance and Repair Cleaning the Stray Light Filter Cleaning the Stray Light Filter 1
97. ter 26 input load 50 instrument description 22 layout and construction 26 parts breakdown 139 141 integration time 46 intensity averaging 46 run buffer 47 test 96 interface control 43 interference 26 internal Index 163 cabinet 26 connections 62 events 43 internal memory exchanging 118 upgrading 118 isopropanol 102 103 isopropyl alcohol 102 103 K key pad 116 exchanging 116 removing 116 replacing 116 keyboard 112 116 exchanging 116 removing 116 replacing 116 keyboard cable removing 109 kinetics measurements 118 L lamps 19 access through door 25 deuterium 19 40 47 96 do not ignite 96 fixing 99 lifetime 98 mercury 47 tungsten 19 40 96 zinc argon 47 layout and construction of instrument 26 lens 19 21 lenses cleaning 103 photographic 102 104 lifetime of lamp 98 light emission of deuterium lamp 40 light pipe 133 134 removing 134 line centroids 48 line frequency 11 line power input socket 25 switch 22 line voltage 11 lock mechanism 96 logarithm of intensity spectrum 46 logic true 50 low pass filter 38 42 LPS board 120 121 M main microprocessor 35 main power supply 32 block diagram 32 connector 63 exchanging 133 removing 133 replacing 134 reset 33 maintenance 94 procedures 94 materials 138 measure push buttons 23 memory 36 exchanging 118 non volatile random access 35 program 35 system 35 upgrading 118
98. terium lamp 47 of mercury lamp 47 of zinc argon lamp 47 E Pak packaging 26 EPLD electronically programmable logic device 38 European Pharmacopoeia 13 exchanging internal memory 118 key pad 116 keyboard 116 the deuterium lamp 94 96 the fan assembly 126 the main power supply 133 the optical unit 122 the SDA board 128 the shutter assembly 124 the SLS board 130 the SPM board 120 the tungsten lamp 94 96 exploded views 138 external cabinet 26 cables 51 communication 50 eye damage 97 F fan assembly 126 exchanging 126 removing 126 replacing 126 fan cable 120 121 126 fan connector 63 filament control of deuterium lamp 40 filter for stray light correction 19 20 47 fingerprints on lamp 98 firmware description 43 loading errors 147 resident part of 43 update procedures 147 updates 43 fixing lamps 99 flatness of baseline 13 flow of raw data 43 forced cold start settings 147 front covers parts 142 removing 109 replacing 111 front panel 42 front view of spectrophotometer 22 fuse 32 G gain correction 45 table 45 general purpose GPIO cable 54 GPIB address 146 connector 25 GPIO connector 24 51 52 53 grating 19 21 grounding kit 108 H hardware fuse 32 hardware handshake CTS RTR 148 hazard eye damage 97 skin burn 98 holographic grating 19 21 humidity 11 I ignition of deuterium lamp 40 indicator 22 industrial design of spectrophotome
99. the green light on the front panel comes on and that you can do a blank measurement from your software Cleaning the Source Lens from the Lamp Side It is not recommended to clean this lens at regular intervals because the lamp housing is sealed against dust Therefore the source lens is not very likely to get dirty from this side However if you have cleaned the other lenses and your intensity test in your operating software still falls below the specified level try the procedure below 1 Turn off the spectrophotometer and disconnect the power cord 2 To remove the Deuterium lamp see Exchanging the Deuterium or Tungsten Lamp on page 96 3 Dampen a lint free surgical cotton swab with reagent grade isopropanol isopropyl alcohol and gently swab the surface of the source lens Repeat several times with clean swabs and alcohol each time Source lens 105 Maintenance and Repair Cleaning the Lenses Figure 19 Cleaning the Source Lens from the Lamp Side 4 Use a canister of compressed oil free air like those used to clean photographic lenses to further clean the source lens If you do not have a compressed air canister you can use a photographic lens cleaning brush 5 To replace the Deuterium lamp see Exchanging the Deuterium or Tungsten Lamp on page 96 6 Reconnect line power and turn on the instrument Check that the spectrophotometer passes its self test this means that the green light on the front panel come
100. the plastic and sheet metal front and rear covers off see Removing and Replacing Covers on page 109 2 To remove the optical unit see Removing the Optical Unit on page 122 3 To remove the fan see Removing the Fan Assembly on page 126 4 To remove the SPM board see Removing the SPM Board on page 120 5 Remove the middle rear foam block Figure 43 Removing the Middle Rear Foam Block 6 To slide the SLS board out of the tab on the right side lift up the SLS board on the left side a little and slide it to the left middle rear foam 131 Maintenance and Repair Exchanging SLS Board Figure 44 Removing the SLS Board Replacing the SLS Board 1 Slide the SLS board into the tab on the right side and push it down see figure above 2 Connect the flat ribbon cable that leads to the SPM board 3 Replace the middle rear foam block Figure 45 Replacing the Middle Rear Foam Block Tab to hold SLS board SLS board 132 Maintenance and Repair Exchanging SLS Board 4 To replace the SPM board see Replacing the SPM Board on page 121 5 To replace the fan see Replacing the Fan Assembly on page 126 6 To replace the optical unit see on page 123 7 Replace the plastic and sheet metal rear cover Push the plastic rear cover down so that it locates on both sides see Removing and Replacing Covers on page 109 8 Reconnect line power and turn on the instrument Check that the sp
101. the multicell transport RS232 and other peripheral devices Shutter control allows for dark current or sample measurements and utilizes the stray light filter Stray light correction is calculated by combining information of two spectra a spectrum measured with the stray light correction filter and a spectrum without the stray light correction filter in the light path Memory for approximately 100 full spectra is available and two SIMM sockets for extending the memory to be able to store several hundred spectra are available SLS Spectrophotometer Lamp Supply Board The SLS board provides control and regulation for both the tungsten and deuterium lamps Spectrograph The spectrograph contains the PDA photodiode array which gives an analog signal proportional to the light level which falls on the individual photodiode during a defined period of time The photodiode array is connected to the spectrophotometer data acqisition SDA board through the spectrograph connector interface SCI board A temperature sensor is located on the diode array for temperature compensation that is to reduce drift This is especially important for the SWNIR part of the spectrum where drift with temperature is significant due to variation in the quantum efficiency of the photodiodes 31 Theory of Operation Electronics Overview SDA Spectrophotometer Data Acquisition Board On the SDA board the signals from the photodiode array are adjusted to an
102. tware you can switch off the stray light correction ChemStation software in case you want to do very fast repetitive scans or it is switched off automatically handheld controller software Sample Compartment The spectrophotometer has an open sample compartment for easier access to sample cells Because of the optical design a cover for the sample area is not required The spectrophotometer is supplied with a single cell cell holder already installed in the sample compartment This can be replaced with the Peltier temperature control accessory the thermostattable cell holder the adjustable cell holder the long path cell holder or the multicell transport All of these optional cell holders mount in the sample compartment using the same quick simple mounting system An optical filter wheel is also available for use with the spectrophotometer and most of the accessories Spectrograph The spectrograph housing material is ceramic to reduce thermal effects to a minimum It main components of the spectrograph are the lens the slit the grating and the photodiode array with front end electronics The mean 21 Theory of Operation Optical System Overview sampling interval of the diode array is 0 9 nm over the wavelength range 190 nm to 1100 nm The nominal spectral slitwidth is 1 nm Spectrograph Lens The spectrograph lens is the first of the parts which are collectively known as the spectrograph It is mounted on the housing of the spe
103. ving and Replacing Covers on page 109 2 Remove any accessory board or MIO board that may be plugged in from the rear side of the instrument Figure 36 Removing MIO or Accessory Boards 3 Remove the upper rear foam block 4 Disconnect the connector from the power supply to the SPM board right the flat ribbon cables from the SDA and LPS boards which are above each other the shutter cable and the fan cable 121 Maintenance and Repair Exchanging the SPM Board Figure 37 Removing Connectors and Screws from SPM Board 5 Unscrew two screws each at the GPIB connector at the APG remote connector and at the multicell connector and remove the SPM board Replacing the SPM Board 1 Position the SPM board on the middle rear foam block 2 Connect the connector from the power supply to the SPM board right the flat ribbon cables from the SDA and LPS boards which are above each other the shutter cable and the fan cable see Figure 37 3 Fix two screws each at the GPIB connector at the APG remote connector and at the multicell connector 4 Replace the upper rear foam block 5 If available replace any accessory board or MIO board plugged in from the rear side of the instrument 6 Replace the plastic and sheet metal rear cover Push the plastic rear cover down so that it locates on both sides see Removing and Replacing Covers on page 109 7 Reconnect line power and turn on the instrument Check that the spectroph
104. wavelength calibration is still valid Perform a wavelength recalibration with your software 78 Diagnostics and Troubleshooting Error Messages Table 33 Excessive Dark Current Detected On Photodiodes Possible Causes Action Spectrophotometer data acquisition SDA board failure Replace spectrophotometer data acquisition SDA board Photodiode array electronics failure Replace optical unit Table 34 Raw Data Buffer Overflow Possible Cause Action Attempting to acquire large amounts of data within too short of a time period Change data acquisition rate and or change cycle time and or change wavelength range 79 Diagnostics and Troubleshooting Error Messages Table 35 Power Fail Possible Causes Action Instrument power fail Check that instrument power indicator in on No interface link to PC Check that the GPIB cable is properly connected to both Agilent 8453 and PC Incorrect interface settings Check that the GPIB interface setting on the spectrophotometer see section Installing your Agilent 8453 Spectrophotometer in the handbook Installing Your UV visible Spectroscopy System on the GPIB interface in PC see section Installing an GPIB Interface Board in the PC in the handbook Installing Your UV visible Spectroscopy System and in the software configuration see section Installing the UV visible Operating Software in the handbook Installing Your UV visible Spectroscopy Sy
105. xes the shutter assembly to the optical unit and remove the shutter assembly Figure 39 Removing the Shutter Assembly Shutter assembly Shutter screw 125 Maintenance and Repair Exchanging the Shutter Assembly Replacing the Shutter Assembly 1 Position the shutter assembly above the source lens and fix the screw that holds it at the optical unit see Figure 39 Connect the shutter cable to the SPM board 2 Replace the upper rear and upper front foam blocks 3 If available replace any accessory board or MIO board plugged in from the rear side of the instrument 4 Replace the plastic and sheet metal rear covers Push the plastic rear cover down so that it locates on both sides see Removing and Replacing Covers on page 109 5 Reconnect line power and turn on the instrument Check that the spectrophotometer passes its self test this means that the green light on the front panel comes on and that you can do a blank measurement from your software 126 Maintenance and Repair Exchanging the Fan Assembly Exchanging the Fan Assembly The fan assembly part number 3160 1103 is located in the top rear part of the spectrophotometer Removing the Fan Assembly 1 Turn off the spectrophotometer and disconnect the power cord Take the plastic and sheet metal rear covers off see Removing and Replacing Covers on page 109 2 Remove any accessory board or MIO board that may be plugged in from the rear side of the

Agilent 8453 UV-visible Spectroscopy System Service Manual

Contents

Download Pdf Manuals

Related Search

Related Contents