EC9841AS Service Manual
Contents
1. GAS FLOW Current gas flow measured from the flow block Figure 15 displays the flow calibration menu for the 9841AS analyzer 98417601 AS Rev C CHAPTER 3 MAINTENANCE FLOW CALIBRATION MENU FLOW BLOCK TYPE ISO CRITICAL ORIFICE 0 640 PRESSURE 1 HIGH 743 0 TORR PRESSURE 1 LOW 250 0 TORR VALVE SEQUENCING ON AMBIENT PRESSURE 750 0 TORR GAS PRESSURE 250 0 TORR GAS FLOW 0 640 SLPM Figure 15 Flow and Pressure Calibration Menu combined 3 5 Flow Pressure Calibration The pressure and flow calibrations should be performed whenever a flow or pressure reading becomes suspect when a transducer is replaced or can be performed as an annual maintenance item This procedure recalibrates both pressure transducers 3 5 1 Setup The following equipment is required e Pressure transducer absolute calibrated in torr e Flowmeter 1 slpm nominal e 1 fitting with hose to suit pressure transducer 3 5 2 Pressure Calibration Note The EC9841AS analyzer should be left running for at least one hour with the pump switched on before this procedure is attempted This will allow the valve manifold temperature to stabilize to 50 C Warning After removal of power from the EC9841AS the exhaust should be maintained for approximately 15 minutes to purge the exhaust of ozone and prevent possible combustion of the charcoal 98417601 AS Rev A 35 EC9841AS NOx ANALYZER SERVICE MANUAL PRESSURE CALIBRATION MENU PRESSURE 1 HIGH2. 0 a CTA 7 O l CS LLLELA ZONE VT TZ 7 Figure 4 Flow Diagram The EC9800 analyzer family uses the advanced digital Kalman filter This filter provides the best possible compromise between response time and noise reduction for the type of signal and noise present in ambient air analyzers and their application The Ecotech implementation of the filter enhances the analyzer s measurement method by making the time constant variable depending on the change rate of the measured value If the signal rate is changing rapidly the instrument is allowed to respond quickly When the signal is steady a long integration time is used to reduce noise The system continuously analyzes the signal and uses the appropriate filtering time Ecotech analyzers have passed USEPA equivalency testing using this advanced signal filtering method 2 1 Instrument Description The instrument is designed in a modular format consisting of a power microprocessor module and a sensor module The power microprocessor module contains the power supply voltage regulators and the system microprocessor The sensor module contains all components necessary to measure the pollutant gas 2 1 1 Power Microprocessor Module The power microprocessor module can be described in three sections the power supply the voltage regulator and the microprocessor 10 98417601 AS Rev C CHAPTER 2 THEORY OF OPERATION 2 1 1 1 Power Supply The power supply is a self c
3. Pressure Calibration oooononononnnnnnnno 37 Illustrations Cable ConnectioONS coooocccnonocononancnononnns 8 Illustrations Cooler Replacement 00 0 0 cesses 29 Illustrations Flow Diagram 10 Illustrations Instrument Status Ranges 33 35 36 38 47 Illustrations Major Components ee eeeeeeeeeees 13 Illustrations Opening the Front Panel o 6 Illustrations Pneumatic Diagram oooonooncnnccnicnnncnnns 14 Illustrations Preprocessor Pots Menu 44 Illustrations Pressure Transducer Replacement 31 Illustrations Reaction Cell Cleaning cee 30 Illustrations Routine Maintenance Components 22 Illustrations Sintered Filter Orifice Removal 25 Illustrations System Block Diagram cee 12 Illustrations System Temperatures and Tolerances 47 Illustrations Valve Test Menu ooocnnnoncconononcnononanonns 45 Installation me 6 98417601 AS Rev A EC9841AS NOx ANALYZER SERVICE MANUAL Instrument Status Ranges illustration 33 35 36 38 47 Instrument Status SCreeN cccoooooncnocccnnoonnncnnnnnnncnnnnnons 46 L Li akstestisscaisc a aan nats 32 M Maintenance periodic ce eeeeeseeeeeecneeeeeneeeeeees 18 Maintenance routine ooooocccccnnnnonnnonoconnnanananonicinnnnns 21 Major Components illustration ooooicoicnonnm 13 Measure modes oucanina censales 16 Microprocessor board ooooococcnoconoconoconononcnnnncnnn
4. channel The instrument consists of a pneumatic system an NO to NO converter molycon a reaction cell detector PMT and processing electronics The analysis of nitrogen oxides by chemilluminescence is generally acknowledged to be the best direct measurement technique The method is based on the luminescence from an activated molecular NO species produced by the reaction between NO and O in an evacuated chamber The NO molecules react with ozone to form the activated species NO according to the reaction mechanism NO O gt NO 0 As the activated species NO reverts to a lower energy state it emits broad band radiation from 500 to 3000 nm with a maximum intensity at approximately 1100 nm Since one NO molecule is required to form one NO molecule the intensity of the chemilluminescent reaction is directly proportional to the NO concentration in the sample The PMT current is then directly proportional to the chemiluminescence intensity In order to measure the zero offset of the instrument a background measurement is performed every 70 seconds by diverting the sample flow from the reaction cell to the cell bypass line This measurement is electronically subtracted from all subsequent measurements to achieve very stable measurements The simplified flow diagram is illustrated in Figure 4 below 98417601 AS Rev A 9 EC9841AS NOx ANALYZER SERVICE MANUAL A ee A Ny gt A P77 CLAS Z7 AS D A a A eZ SAL
5. display Microprocessor PCA 2 Replace the microprocessor board 3 A bad cable is unlikely but if you suspect it perform a pin for pin continuity test using an ohmmeter 3 Zero flow Pump failed Replace the pump Filter Check the particulate filter Replace if dirty or plugged Pressurized Rx cell Ensure sample and zero inlets are maintained at ambient pressure Plugged orifice or Clean or replace the orifice and SS filter SS filter 98417601 AS Rev A 49 EC9841AS NOx ANALYZER SERVICE MANUAL Possible Cause Leaks Symptom 4 Noisy or unstable readings Particulate filter Unstable flow or pressure Temperature Calibration Ozone generator PMT 5 Low span Span setting Leaks Molycon Temperature Reaction cell PMT gain 6 No response to span gas Span setting Leaks No flow Detector System Troubleshooting Table Fault Isolation Solution A leak dilutes the sample stream and causes low span readings Variation in the leak causes noise Perform a leak test as described in section 3 3 10 A contaminated filter causes numerous problems Replace the particulate filter Verify that the flow and pressure readings on the INSTRUMENT STATUS screen are within acceptable limits and steady Verify that the temperatures on the SYSTEM TEMPERATURES screen are within the acceptable limits and steady Check for incorrect calibration or unstabl
6. helpful to mark the pneumatic fittings prior to removal to ensure they are reconnected to the proper port Refer to Figure 10 for sintered filter locations in the manifold Replace the sintered filters If desired the orifices may be replaced cleaned with alcohol or cleaned in an ultrasonic bath Reassemble the manifold assembly in reverse order of the above steps Figure 10 Sintered Filter Orifice Removal 25 EC9841AS NOx ANALYZER SERVICE MANUAL 26 3 3 7 PMT Desiccant Pack Replacement The PMT housing contains two desiccant packs to prevent condensation on the cooled PMT housing If the desiccant expires it will result in corrosion of the PMT housing and premature cooler failure It is recommended that the desiccant bags be changed at least annually If moisture is detected inside the housing or the desiccant packs are saturated the interval should be reduced To change the desiccant packs perform the following Warning After removal of power from the EC9841AS the exhaust should be maintained for approximately 15 minutes to purge the exhaust of ozone and prevent possible combustion of the charcoal Caution Because the PMT is extremely sensitive to light it is essential that before opening the PMT assembly to make sure that the analyzer is switched off In addition even when the analyzer is switched off is very important to cover the PMT at all times so that no direct light reaches its window 1 Turn the
7. the molycon This sample will remain resident in this loop until the NO measurement cycle where the sample will be pulled from this loop through the molycon and into the reaction cell for measurement This helps minimize artifact anomalies from dissimilar measurement samples Molycon Converter The EC9841AS analyzer uses a molybdenum converter for reducing NO to NO Molybdenum reacts with NO at near 315 C to form molybdenum oxide and NO At this temperature other nitrogen compounds such as ammonia are not oxidized to NO Valve Manifold The valve manifold controls all of the pneumatic switching of the NO and NO gas samples for the measurement and background cycles and the sample and bypass flow control orifices The manifold also contains a pressure transducer and pressure PCA to support the transducers As the critical orifices and the pressure transducer are temperature sensitive the valve manifold is temperature controlled 98417601 AS Rev C CHAPTER 2 THEORY OF OPERATION Pressure Transducers Two pressure transducers are present in the EC9841AS One is in the manifold which measures the pressure upstream of the critical orifices ambient pressure The other transducer is located in the reaction cell downstream of the critical orifices gas pressure Sample flow rate is calculated by measuring the upstream ambient pressure of the critical sample orifice Pump The external pump pulls a strong vacuum to maintain cons
8. 743 0 TORR PRESSURE 1 LOW 250 0 TORR VALVE SEQUENCING ON AMBIENT PRESSURE GAS PRESSURE GAS FLOW Figure 16 Pressure Calibration Menu for ISO Flow Block From the TEST MENU select OZONATOR OFF After 15 minutes turn off the pump From the HIDDEN MENU set the FLOW BLOCK TYPE TO ISO and press Enter gt 1 Press Reset on the analyzer secondary panel Disconnect the Teflon line from the O generator to the measurement cell and connect a calibrated pressure transducer to this port on the measurement cell as shown in Figure 17 From the HIDDEN MENU select the PRESSURE CALIBRATION MENU The menu of Figure 16 should be displayed Allow 30 seconds for the pressure reading to stabilize to ambient pressure on both the calibrated pressure transducer and the analyzer This reading in TORR should be the ambient pressure Set this value as PRESSURE 1 HIGH in the PRESSURE CALIBRATION MENU and press Enter gt 4 Note To convert from millibar to TORR multiply the pressure by 0 75 Connect the pump to the exhaust port and turn on the pump From the PRESSURE CALIBRATION MENU Set the VALVE SEQUENCING OFF and press Enter gt J 98417601 AS Rev C 11 12 13 CHAPTER 3 MAINTENANCE Allow the pump to evacuate the cell and the pressure reading to stabilize This reading should be low typically 100 to 200 torr and is dependent upon the capacity of the pump This reading shou
9. APTER 4 TROUBLESHOOTING 4 4 Troubleshooting Guide Use this troubleshooting guide to find the symptom Then follow in order the possible causes and the fault isolation solution procedures until the problem is discovered Then take the action described If you cannot identify the problem contact Ecotech at the locations given in the front of this manual System Troubleshooting Table Symptom Possible Cause Fault Isolation Solution 1 No display AC power 1 Verify that the line cord is connected instrument dead 2 Check that the power supply fuse is not open The fuse should be 5A 115 v or 3A 230 v 3 Verify that the Voltage switch on the power supply is in the proper position 2 No display Contrast Set or adjust the display contrast simultaneously misadjusted pressing two keys on the front panel as follows Contrast Press Up arrow A and lt Select gt for darker contrast Down arrow Y and lt Select gt for lighter contrast DC power 1 Verify the cable connection from the power supply to the VReg board 2 Check the VReg board for correct voltages as listed in the Troubleshooting Voltages table in section 4 1 If incorrect voltages are found replace the power supply or VReg 3 Check Microprocessor test points listed in the Troubleshooting Voltages table table in section 4 1 Display Check the interface cable between the display and J6 on the Microprocessor board Bad display or 1 Replace the front panel
10. ES to A or B depending on which analyzer it is Then press Enter gt 2 Set the ANALYSER TYPE to 9841as and press Enter gt 1 3 Press Reset on the analyzer secondary panel The display should now display 9841AS NOX ANALYZER 4 You may need to erase memory after this procedure to avoid any problems This completes the analyzer device type programming 38 98417601 AS Rev C CHAPTER 3 MAINTENANCE 3 7 Firmware Update As improvements are made to the EC9800 series analyzers these can be easily passed on to the user by updating the firmware software operating within the Microprocessor board To update your EC9800 Analyzer download the Firmware Updater Software Install this software on a Windows based computer with a COM port To do this run the downloaded file setup exe by double clicking on it then follow the installation screens to install Next download the required software version for your 9800 analyzer from those listed at the bottom of this page e g V1 00 0002 by right clicking on the link and choosing Save Target As and saving the sx file on your computer You will need to select save as type All Files in the download window To update the firmware on the analyzer 1 Run Firmware Updater from the Start Programs Ecotech Firmware Updater menu 2 Connect the 9800 analyzer to the computer using a standard serial cable you can connect to either the Multidrop port on the back of th
11. N RATIO gt 1 25 RESET DETECTION AZS CYCLE DATA LOGGING MEM FAIL CONTROL LOOP RESTARTED VALVE SEQUENCING RESTARTED Event Log Messages Description Action Instrument flow has gone to The pump has been turned off Zero or has failed After AZS cycle ratio of requested span to measured span is lt 0 75 Instrument span has drifted beyond acceptable limits Recalibrate as necessary After AZS cycle ratio of requested span to measured span is gt 1 25 Instrument span has drifted beyond acceptable limits Recalibrate as necessary Unless the reset was not initiated by the user no action is required AZS cycle started No action required Occurs if unable to write to Battery failure or system datalogging memory software error If error persists call Ecotech Customer Service for instructions Reset button pressed or watchdog timer caused reset Occurs when Control Loop has been disabled and then automatically enabled after the main screen has been visible for the last 1 minute No action required Occurs when valve sequencing has been disabled and then automatically enabled after the main screen has been visible for the last 1 minute No action required 4 2 4 Instrument Status If any of the parameters displayed on the INSTRUMENT STATUS screen vary significantly from the values show
12. NO concentrations which are then compared to determine the raw NO concentration The background cycle allows for an automatic zero correction to eliminate PMT dark current and cell contamination offsets from the PMT During background the sample is switched past the reaction cell and only O3 is allowed to enter the cell The resultant reaction level is measured and subtracted from subsequent NO and NO calculations 2 2 2 1 Zero Zero measure allows the sample to be switched to a zero air source either through the EZS valves or from the IZS module Processing of the signal is identical to measurement processing the only difference is the source of the sample stream 2 2 2 2 Span Span measure allows the sample to be switched to a span gas source either through the EZS valves or from the IZS module Processing of the signal is identical to measurement processing the only difference is the source of the sample stream 2 2 2 3 AZS Cycle The analyzer can be placed in an AZS cycle mode where the sample stream is automatically switched to zero then span then back to sample For further information on the AZS cycles refer to the EC9841AS Operation Manual 98417601 AS Rev A 17 EC9841AS NOx ANALYZER SERVICE MANUAL 3 0 Maintenance 3 1 Maintenance Schedule The following outlines a periodic maintenance schedule for the EC9841AS analyzer This schedule is based on experience under normal operating conditions and may need to be mod
13. PMT cold block Ensure the orientation of the red black wires on the cooler when viewed from the wire side of the cooler are red on the right and black on the left Place the PMT cold block and cooler on the heatsink and secure with the screws from the underside of the heatsink Ensure the shoulder washers and neoprene washers are properly in place around the screws Caution Alternately tighten each of the screws securing the PMT cold block to the heatsink approximately 1 4 turn until the PMT housing and heatsink are secured flush with the cooler face and the screws are snug Do not over tighten Connect the cooler wires to the electrical connector red wire to pin 13 and black wire to pin 12 Reinstall the PMT housing cover ensuring that the O ring on the base of the cover remains in place Install two new desiccant packs in the PMT housing Reconnect the desiccant access cap electrical connector and reinstall the access Cap Caution Do not attempt to install the desiccant cap into the PMT housing by using the screws to pull the cap into place This will damage the PMT housing A small amount of lubricant on the desiccant cap O ring will facilitate its installation 98417601 AS Rev C CHAPTER 3 MAINTENANCE i VILL R A H tf AN A e AX Figure 11 Cooler Replacement 3 3 9 Reaction Cell Cleaning As O3 reacts with the contamina
14. YH ecotech environmen tal monitoring solutions EC9841AS Oxides of Nitrogen Analyser High Level Service Manual www ecotech com FRONT MATTER Table of Contents MANUAL HISTORY vetada azi a E a Es 3 SAFETY REQUIREMENTS oi iii 4 SERVICE AND SPARE PARTS oiriin eireas raene a Ee ee AEE E Ee eer eeN EEES R EErEE Eo SaR EEEE Ere ariak iae 5 1 0 A A TN 6 VEL INITIAL CHECK e e add iii iaa 6 LAT Remove the Top COVA dada 6 L I2 Service WU CA A conde ess te eee ERE Sau ahah ce he a SO ERR REE 7 L SInspectthe Components ennnen e a led vhs esa 7 LL AReinsert DISlOd e ed Boards A a A a aE 8 PASS Cable CONME CHONS iii aiii 8 2 0 THEORY OF OPERATION esscisceccsscssasasecscsstevinns cadacsoacssoanssessesecedsentosbacsoonssndoabeasessedadeadssbacdesssecenavesonssesscsesenoostes 9 2 1 INSTRUMENT DESCRIPTION sree arie ereer oek orreee E cede Ee iae E RAEE EEE AEREA E cotdacteessvedcecayeaeds cavdeceseatdecesents 10 2 1 1 Power Microprocessor Mod le erenn iieii i AE E ER A OARA E E Ta RAVE ai 10 D 1s2 SENS OV MOGUIC tad 13 2 2 OPERATION MODES sad 16 22 1 Slartip MOdesia eae vae aia A A A eas SR E A ae 16 22 2 Med re MODES fei co aise BRC eee A A Bs REE EN NEN ES IEEE aR ESE 16 3 0 MAINTENANCE occicscccecssisasstastctsesscsacscconssnanascaneseeasdenastosssessssonedcesoasseascssbodeessassassoncesdesscsnadsaeistascessessseaseoesesenee 18 3 1 MAINTENANCE CHEDULE e a ias 18 3 2 REPLACEABLE PARTS ias 19 3 2 1 Expected Life Span of COnSUumabl
15. al is current for firmware version 1 11 and above This manual should only be used in conjunction with EC984 AS Nitrogen Oxides Operation Manual PN 98417600 AS Rev C May 2007 Ecotech Manual ID MAN 0014 Manual PN 98417601 AS Current Revision C Date Released May 2007 Description EC9841AS Nitrogen Oxides Service Manual Revision History Rev Date Summary Affected Pages A June 2005 New Release for new Microprocessor Board Based All on original manual C December Updated specifications language and links within All 2006 98417601 AS Rev C pdf manual created EC9841AS NOx ANALYZER SERVICE MANUAL Safety Requirements o To reduce risk of personal injury caused by electrical shock follow all safety no tices and warnings in this documentation o This equipment should always be used with a protective earth installed o The EC9841AS is compliant with the requirements of EN61010 1 A2 1995 Safety Requirements for Equipment for Measurement Control and Laboratory Use o If the equipment is used for purposes not specified by the manufacturer the pro tection provided by this equipment may be impaired o Replacement of any part should only be carried out by qualified personnel only using parts specified by the manufacturer Always disconnect power source before removing or replacing any components o The Ozone Generator contains dangerous levels of voltage Make sure the power is disconnected when opening the gene
16. ally adjusted potentiometers for contrast level All analog voltages from the sensor assembly are digitized by the analog to digital A D converter for microprocessor use Digital to analog D A conversion of three channels is used to send 0 to 20 mA analog signals to the 50 pin I O connector The microprocessor has electrically erasable ROMs which store the operating program and internally logged data Program upgrades can be easily made through the serial port The Service and Reset switches are located on the front of the board and are accessible when the top is removed or when the front panel is opened The microprocessor also has provisions for USB and optional TCIP connections through the rare panel 98417601 AS Rev A 11 EC9841AS NOx ANALYZER SERVICE MANUAL 12 Figure 5 System Block Diagram MOLYCON o E GENERATOR FAN REACTION OPTICAL FAN CELL BENCH VALVE MANIFOLD NOx PRE PROCESSOR BOARD 1 VOLTAGE REGULATOR BOARD POWER SUPPLY BATTERY MICROPROCESSOR BOARD FRONT REAR Figure 6 Major Components 98417601 AS Rev C CHAPTER 2 THEORY OF OPERATION 2 1 2 Sensor Module The sensor module comprises three areas of description pneumatics optics and electronics 2 1 2 1 Pneumatics The pneumatic system continuously supplies sample air to the reaction cell at a constant rate allowing the sample to be measured before exiting the analyzer Se
17. analyzer off and disconnect power 2 Using a Phillips head screwdriver remove the desiccant pack access cap from the PMT housing Refer to Figure 8 3 Remove the old desiccant packs and replace with new Do not attempt to dry and reuse the old packs 4 Inspect the inside of the PMT housing by touch or with an inspection mirror to check for moisture inside the housing If moisture is detected inside the housing the desiccant pack replacement interval should be decreased 5 Reinstall the desiccant cap by gently twisting and pressing the cap back into the PMT housing It may help to apply a small amount of lubricant to the O ring on the desiccant cap Secure with two screws Caution Do not attempt to insert the desiccant cap into the PMT housing by using the screws to pull the cap into place This will damage the PMT housing 6 Reconnect power and restart the analyzer 98417601 AS Rev C CHAPTER 3 MAINTENANCE 3 3 8 PMT Cooler Replacement 98417601 AS Rev A Warning After removal of power from the EC9841AS the exhaust should be maintained for approximately 15 minutes to purge the exhaust of ozone and prevent possible combustion of the charcoal Caution Because the PMT is extremely sensitive to light it is essential that before opening the PMT assembly to make sure that the analyzer is switched off In addition even when the analyzer is switched off is very important to cover the PMT at all times so that no direc
18. and retain the Kynar nut from the end of the DFU 3 Remove and replace the DFU ensuring that direction of flow is correct from rear to front of analyzer 4 Reinstall the Kynar nut ensuring that the ferrules are properly installed in the nuts 5 Turn on the pump 3 3 6 Sintered Filter Replacement The sintered filter is used as a final filter to prevent contamination and blockage of the sample orifice If the filter becomes plugged it will result in loss of sample flow through the analyzer Typically replacement of the sintered filter alone will be sufficient to maintain operation but occasionally the orifices should be checked and cleaned to ensure proper operation 98417601 AS Rev C 98417601 AS Rev A CHAPTER 3 MAINTENANCE Warning After removal of power from the EC9841AS the exhaust should be maintained for approximately 15 minutes to purge the exhaust of ozone and prevent possible combustion of the charcoal Caution Take extreme care not to damage the pressure transducer assemblies on top of the reaction cell and on the side of the valve manifold Turn off the analyzer and disconnect the pump Remove the four screws securing the pressure PCA to the valve manifold and disconnect and remove the PCA Refer to Figure 10 Disconnect the electrical and pneumatic fittings from the manifold assembly loosen the captive screws securing the manifold to the standoffs and remove the manifold from the analyzer It may be
19. cer assembly pressure 98412033SP Dryer assembly PermaPure 98412046 Level 1 General maintenance supplies and expendables such as filters O rings lamps etc Level 2 Critical items that are known from experience to have a higher failure rate such as pumps heaters converters valves and circuit boards Level 3 Other miscellaneous items not included in Level 1 or 2 This level includes other spare parts that are not expected to fail over a given time frame Components marked with shading are essential components which need to be kept on hand at all times EC9841AS Analyzer Spare Parts Requirements Options and Accessories Description Part Number Pump external 115V 60 Hz 4 slpm at 20 inches Hg 884 017300 Pump external 110V 50 Hz 4 slpm at 20 inches Hg 884 017301 Pump external 230V 50 Hz 4 slpm at 20 inches Hg 884 017302 Pump external 110V 50 Hz 4 slpm at 20 inches Hg 884 017303 Rack mount kit with slides 98000036 2 PCA 50 Pin I O 98000066 2 Battery power option 12 VDC 98000115 Filter particulate sample inlet 5 micron 98000210 1 Filter kit particulate sample inlet 5 micron 98000211 1 50 pin connector and shell kit 98000235 1 Valve manifold kit external zero span EZS 98300087 Scrubber charcoal 98415105 7 EC9841AS Operation Manual 98417600 EC9841AS Service Manual 98417601 98417601 AS Rev C CHAPTER 3 MAINTENANCE EC9841AS Analyzer Spare Parts Requirements Options a
20. cnnncnnoo 11 Modes of Operation ceeecsesecsseeeeesecseeeeeneeeeeees 16 Molycon COnverter ceeecceeeeeesseceeeeecsseceeeeecsaeeeenes 14 O Opening the Front Panel illustration 6 Optic test FUNCTION ococonoconoconcncccnnonnnnncnnononcnnncnnnno noo 49 Optical bandpass filter oooooonconicnninnnnnnccnccnocnconncnnno 15 Optics system components cecceesceeseeeeeeeeeeees 15 P Particulate filter maintenance ooooocccnoonnoonccnonaninnnos 22 Periodic MaintenanCe cocooccooncnonononnncconnnoonccconononnnoo 18 Photomultiplier tube ee eeeeceseceeeseceeeeeeneeeeeens 15 PM Tiida 15 PMT cooler replacement coooocnoccconocononanoccnonnncnnnnoos 27 PMT desiccant pack replacement oooonccnnnnninninninm 26 Pneumatic Diagram illustration cee 14 Power microprocessor module ce eeeeeeeeeeeeeeeee 10 Preamp test function ooooononccnocnnononononcnnonocononnonnnnninos 49 Preprocessor board ooooooccnocccoconocononconnnononanonanonnncnnoon 15 Preprocessor Pots Menu eeceeseecsseceeneeceseeeeneees 44 Preprocessor Pots Menu illustration 44 Pressure Calibration illustration c ccccsceeees 37 Pressure Transducer Replacement illustration 31 Pressure transducers ccssccccesssecesseseeceessececsseaees 15 Pressure transducers handling ooonccnnonicnicncnniccns 31 PUMP toa 15 R Reaction cella ic o Gia dei 15 Reaction ce
21. con miscellaneous logic to generate test signals and control the ozone generator The DC circuitry consists of a DC amplifier and signal conditioning circuit The controls include an input potentiometer to set the input gain of the circuit and a variable gain amplifier to maximize the dynamic range of the measurement channel all under control of the microprocessor EC9841AS NOx ANALYZER SERVICE MANUAL 16 o The TE cooler circuit controls the PMT to 10 C while heater circuits control the reaction cell to 50 C and the molycon to 315 C Test signals are generated for built in diagnostics The control for the ozone generator is a pass through signal from the microprocessor 2 2 Operation Modes The analyzer operates in a number of different measurement modes These modes include startup measurement and auto zero modes Following is a description of each of the operating modes 2 2 1 Startup Mode When the instrument is initially powered up several components in the instrument are allowed to warm up prior to operation During this time data is reported but should not be considered valid until the START UP SEQUENCE ACTIVE message is no longer displayed In addition the ozonator will not turn on until flow is sensed and converter temperature is above 250 C This process typically requires about 60 minutes 2 2 1 1 Quick Start Routine If the analyzer power is removed for less than two minutes the full automat
22. e Figure 7 for the pneumatic diagram The pump pulls a strong vacuum that draws sample air into the inlet and through the particulate filter The sample flows both directly to the valve manifold NO port and through a sample delay coil and the molycon to the valve manifold NO port Within the valve manifold the sample then flows through the critical orifice which maintains constant flow and strong vacuum in the reaction cell The sample is selected to either come from the NO port or from the NO port to the reaction cell via the sample switching valves Sample then flows to the reaction cell for measurement and out to the external exhaust scrubber and pump The EC9841AS performs a dynamic auto zero of the instrument by diverting the sample past the reaction cell to the cell bypass line This results in a background measurement of the remaining reaction signal o Particulate Filter The particulate filter is designed to remove particles larger than 5 microns and to expose the sample to only nonreactive materials of Kynar Teflon and Viton The filtering agent is a 47 mm diameter 5 micron filter 98417601 AS Rev A 13 EC9841AS NOx ANALYZER SERVICE MANUAL 14 S Figure 7 Pneumatic Diagram Delay Loop The delay volume loop allows the analyzer to measure NO and NO from the same physical sample As sample is drawn directly into the reaction cell for NO it is also drawn into the delay loop upstream of
23. e EC9841AS are STANDARD TRACE amp HIGH LVL 98417601 AS Rev A 33 EC9841AS NOx ANALYZER SERVICE MANUAL 34 GAS NAME Allows the user to set a 3 character name for the primary gas name NO The name entered here will be used to replace the primary gas name NO in all screens If the first character is a space then NO will be used as a gas name FLOW BLOCK TYPE Displays the type of flow block installed If the flow block is not connected or calibrated then no type will be displayed For all EC9841 series analyzers the flow blocks type should be set to Iso 3 4 1 Pressure amp Flow Calibration sub menus The pressure and flow calibration menus allow the user to manually calibrate the pressure transducers and calibrate the flow of the flow controllers The contents of the pressure and flow calibration menus are described below CRITICAL ORIFICE Designated flow rate of the critical orifice installed in the flow pressure assembly For the 9841AS this should be set to 0 64 unless otherwise specified PRESSURE 1 HIGH Pressure entered during ambient calibration PRESSURE 1 LOW Pressure entered during low pressure calibration VALVE SEQUENCING Turn the valve sequencing on or off Same as in the Valve Test Menu When turned off the appropriate valve sequence will set ready for pressure calibration AMBIENT PRESSURE Current pressure measured from the flow block GAS PRESSURE Current pressure measured from the flow block
24. e Mains supply is within the correct operating range 4 2 Troubleshooting the EC9841AS Analyzer Because of the sophisticated design of the EC9841AS analyzer a significant amount of information about the condition of the system is available on the front panel display You can therefore troubleshoot an operating instrument without opening the front cover The most useful menus in terms of troubleshooting are O PREPROCESSOR POTS MENU 98417601 AS Rev C CHAPTER 4 TROUBLESHOOTING VALVE TEST MENU EVENT LOG INSTRUMENT STATUS SYSTEM TEMPERATURES Q 0 QO 0 SYSTEM FAULTS These menus provide information that may indicate a failure or an operational problem If instrument performance appears to have changed dramatically the component that is causing the problem can possibly be determined thereby speeding up the corrective process It may assist the operator to periodically check and record these parameters to establish an operational history of the analyzer In addition information from this section may be requested by Ecotech service support personnel when assistance is required 4 2 1 Preprocessor Pots Menu The PREPROCESSOR POTS screen displays the potentiometer settings associated with several components variables or signals on the preprocessor board Figure 23 illustrates a typical screen for an instrument that is operating normally The value
25. e analyzer If this filter becomes contaminated with dust and dirt it may affect the cooling capacity of the analyzer The fan screen should be cleaned by removing it from the analyzer and blowing it out with compressed air or by cleaning it with mild soapy water and air drying 98417601 AS Rev A 23 EC9841AS NOx ANALYZER SERVICE MANUAL 24 3 3 4 Exhaust Scrubber The optional exhaust scrubber is essential to the reliability of the pump If the scrubber material expires it will allow O3 to reach the pump which will severely damage the seals of the pump The material in the scrubber should be replaced periodically to ensure the longevity of the pump Warning After removal of power from the EC9841AS the exhaust should be maintained for approximately 15 minutes to purge the exhaust of ozone and prevent possible combustion of the charcoal 3 3 5 DFU Replacement The zero air entering the permapure drier is filtered by a disposable filtration unit DFU to prevent contamination of the pneumatics and Rx cell Failure of the DFU could result in loss of dry air to the O3 generator damaging the generator The DFU is located inside the rear corner of the sensor module To replace the filter Warning After removal of power from the EC9841AS the exhaust should be maintained for approximately 15 minutes to purge the exhaust of ozone and prevent possible combustion of the charcoal 1 Turn off the analyzer and turn off the pump 2 Remove
26. e analyzer or the service port on the front of the analyzer 3 Select Serial Port and the COM Port on the computer from those listed on the Firmware Update screen pl Firmware Update Connect to the analyser via which port type Serial Port Communication Port com y Figure 19 Firmware Update communication settings screenshot 98417601 AS Rev A 39 EC9841AS NOx ANALYZER SERVICE MANUAL 4 Click Next 5 Enter the full path and file name of the firmware sx file you downloaded e g C TEMP V1 03 0001 SX assuming the file was saved to C TEMP W Firmware Update What firmware to do you wish to load CATEMP v1 03 0008 5x lt Browse Details Firmware 1 03 0008 S Date Friday 9 January 2004 3 31 07 PM Size KB 244 Figure 20 Firmware Update firmware selection screenshot 6 Click Next 7 Tick the boxes as shown in the figure below i Firmware Update Select the operations you wish to perform Enter bootloader Erase Flash ROM Erase EEPROM Erase RAM Upload Firmware HHOOAAn Run Firmware Previous Figure 21 Firmware Update operations screenshot 8 Ensure the analyzer is switched off using the switch under the front panel 40 98417601 AS Rev C 10 11 98417601 AS Rev A CHAPTER 3 MAINTENANCE Click Start Switch the analyzer on The Firmware Updater window will show each step as the firmware is uploaded DO NOT turn the analyzer off until the C
27. e gas source Replace the ozone generator Replace the PMT Adjust the span using the calibration procedure in the EC9841AS Operation Manual A leak dilutes the sample stream and causes low span readings Variation in the leak causes noise Perform a leak test as described in section 3 3 10 1 Verify the molycon is 305 to 325 C 2 Verify that the efficiency of the molycon is higher than 96 See the EC9841AS Operation Manual 3 Replace the molycon Verify that the cell temperature on the SYSTEM TEMPERATURES screen is within range Verify that the optical filter is clean Verify that the PMT high voltage is within range INSTRUMENT STATUS screen Adjust the span using the calibration procedure in the EC9841AS Operation Manual A leak dilutes the sample stream and causes low span readings Variation in the leak causes noise Perform a leak test as described in section 3 3 10 See the No air flow symptom in this table 1 Verify that the PMT high voltage is between 650 and 850 v 2 Verify good BNC cable connection between the optical bench and the preprocessor J4 3 Use the Optic Test function to verify PMT response 50 98417601 AS Rev C CHAPTER 4 TROUBLESHOOTING Symptom Possible Cause 6 Cont d Ozone generator Software lockup 7 Zero drift 8 Zero gas will Bad zero air not read Contaminated 0 000 ppm reaction cell 9 Unstable flow or pressure r
28. e rear panel and the DFU filter inlet inside the instrument 3 Enter the INSTRUMENT STATUS screen Both GAS PRESSURE and AMBIENT PRESSURE Should drop to approximately 50 of the normal GAS PRESSURE reading Note If the readings do not drop to within 10 torr of each other there is probably a leak The pneumatic diagram in Figure 7 and the VALVE TEST MENU can be used to isolate portions of the pneumatic system and possibly isolate the leak 4 Return to the OUTPUT TEST MENU choose VALVE TEST MENU and select VALVE SEQUENCING ON 5 Press lt Exit gt and unplug the instrument inlet port and the DFU filter inlet inside the instrument If a leak is detected attempt to isolate the leak by using the VALVE TEST MENU and the pneumatic diagram to select and close off different sections of the analyzer The actual flow through the analyzer should be checked by turning on the exhaust pump and connecting a Flowmeter to the Measure inlet ensure that the analyzer is in SAMPLE MEASURE Actual flow through the analyzer should be approximately 0 62 slpm If flow is too low perform the sintered filter 32 98417601 AS Rev C CHAPTER 3 MAINTENANCE replacement procedure in section 3 3 6 If flow is too high there is probably a leak around the sintered filter or orifice 3 4 Hidden Menu The new software features
29. each 98000098 1 Molycon assembly NO to NO converter 98415207 O ring desiccant access cap 25000422 O ring reaction cell housing 25000423 O ring reaction cell optical filter 25000426 O ring manifold plug 25000447 008 Extraction tool minifit connectors 29000141 2 Tube side on photomultiplier 57000010 Orifice 4 mil 844 012600 Orifice 8 mil 844 012602 Pump external 115V 60 Hz 884 017300 Pump external 100V 50 Hz 884 017301 Pump external 230V 50 Hz 884 017302 Pump external 110V 50 Hz 884 017303 Thermistor assembly 885 071600 PCA Voltage Regulator 98000056 Display switch assembly 98000057SP PCA 50 Pin I O 98000066 2 PCA Microprocessor SMD 98000063 4 PCA USB Board Assembly 98007502 Power supply 115 230 VAC to 12 VDC 98000142 Service kit pump 98000242 Filter optical reaction cell 98410012 PCA Preprocessor 98410033 2 Heater thermistor assembly 12 inch 98410070 2 wojo ou Nu on ou wT ow wo w wo ww NUJ NUJNA wo ww wo wl wo ww w wt vy Ozone generator and housing assembly 98410121 2 Level 98417601 AS Rev A EC9841AS NOx ANALYZER SERVICE MANUAL 20 EC9841AS Analyzer Spare Parts Requirements Description Part Number Level PCA Valve Manifold Pressure Temperature 98412007SP 3 Valve manifold assembly 98412021SP HVPS and preamplifier assembly photomultiplier 98412028 2 SP Cooler thermoelectric 98412028 3 SP Thermistor assembly 98412028 4 SP wt wi lw i wif w ft w Transdu
30. eadings Failed cell control heater 10 Response time Low flow not at specified value 11 PMT voltage does not reach 650 v High voltage Bad Microprocessor or Preprocessor PCA Preprocessor ID set wrong 12 Analyzer displays BAD TD ANALYZER System Troubleshooting Table Fault Isolation Solution 1 Verify that the TEST MENU OZONE GENERATOR ON 2 With the ozone generator ON check the following voltages on the preprocessor board J2 9 12 v J2 11 gt 2 4 VDC 3 Replace the ozone generator Verify that the TEST MENU VALVE SEQUENCING ON 1 Observe whether ECOT display is turning 2 Verify that other menus can be selected 3 Press the Reset button on the secondary panel 4 Check that D5 HEART BEAT LED is flashing on the Microprocessor Board ECH GLOBE on the A leak dilutes the sample stream and causes low span readings and noise Perform a leak test as described in section 3 3 10 Replace zero air source Clean reaction cell The cell temperature SYSTEM TEMPERATURES screen should be 50 5 C Check sample flow with flow meter It should be 0 6 to 0 7 slpm at STP Replace SS filter or orifice if it is not 1 Check the high voltage test point J5 15 Voltage should be at least 2 7 v 2 Check the high voltage control test point J5 7 Voltage should be 0 65 to 0 85 v 3 Replace the preprocessor board Check that D5 HEART BEAT LED is fla
31. es s cccesscsssassensvuscssesseseasoaniges sossnosssednasdbsssedaaes dan Eneas acne 21 3 3 MAINTENANCE PROCEDURES odian lia 21 33 Check Rarticulate Ett a iii 22 3 3 2 Particulate Filter Replacement Procedure A Series ccsccscccsscessessceeseeeseeescesecesecesecanecaceeseenseeeseeseeeeeeeaees 22 3 3 3 Clean Fan Filter sisuna sedat aaa i A N A AE E EE LE ENTIN EEEE NERE r E A Es 23 3 3 4 Exh ust Scrubber iaie eiiie r EE AE Eae E e AREE EEE AEE EE Ae EEE EESE ER aiie 24 3 3 3 DFU Replacem nt sisisi NN 24 3 3 0 Sintered Filter Replacement mirren ken n a eas a e a 24 3 3 7 PMT Desiccant Pack Replacement a E 26 3 3 8 PMT Cooler Replacement zeinei ea EEE cda 27 3 3 VReachon Cell Cleaning cit a A EE EA EO E E OTARA TaS 29 3 3 10 Pressure Transducer Handling sirere aieiaa none neiaa EAE EEE aE A AEREA aaa EERS 31 3 3 11 Leak Test Procedure aiii 32 3 4 HIDDEN MENU ceci 33 3 4 1 Pressure amp Flow Calibration sub menus ccc cccccccccccsssceceescecesssceecuesceceenseeecessueceenssseceesseececssceensnsseeeenaes 34 3 5 FLOW PRESSURE CALIBRATION iii dada daa 35 DIAS CUP A A A A 35 3 5 2 Pressure COlibratiON ooocononnnonoconncnononnannnonocnonnnnn nn nono onononnn nn A E T E E no nnnnncannnns 35 3 3 FLOW CANTARA ta tia dido 38 3 6 PREPROCESSOR ID ENTRA as 38 337 FIRMWARE UPDATE SA A EEEE A riches eens eee hee Rae art 39 4 0 TROUBLESHOOTING y sacssoscssesseocscsevasesscssonscsventscsesscacessaseostesnacsventecsanssencestasesessoesena
32. gsuassenssesnsoceatevenasscasevssssenes 42 4 1 DC POWER SUPPLY VOLTAGES socorro te Andes hie dates Wave dde c hel 42 4 2 TROUBLESHOOTING THE EC9841 AS ANALYZER c ccceseceesceceseeesseceseeeeseeceseeceneeceseeeeneeceaeeseneeceseeseaeeceeeseneeeeee 42 4 2 1 Preprocessor Pots Menil sis cc cisccssassvsesansisecasipshcethnetisesdebeseevdessssuasapobee chest ssussopebantdnssasssbusessedseotisasdagedeedees 43 4 22 Valve Test M enue la td dd ti trates 43 ADS EVE LOB EA E E dt EEA EE its aba 44 98417601 AS Rev C 1 EC9841AS NOx ANALYZER SERVICE MANUAL EZALOSTCUMENPSTA US izideal STE a AA Ei E adn EA A edi ia 45 AZ System Temperatures NN AAN A A AA A aaa 46 4D Ov ys temEQUIES ati Shaheed NI Ai E cs 46 A NA E T a E 47 7 ASPE E O j 2111 OERE oo iss Meets oe EEEE EEE AE EEEE 48 ASI ALS NRO 48 AID MOCOS ds 48 4 3 4 Use of Diagnostic Modes viii die 48 4A TROUBLESHOOTING GUIDE shetten a E T EAT EEEE race seecereoe 49 INDEX AAA ONO I 2 98417601 AS Rev C FRONT MATTER Manual History This manual is a reconstruction of a previous manual used for the operation and service of the 9841AS The original manual was o ML9841AS Service Manual PN 98415202 Rev N October 2001 The scope of this new manual covers the following analyzer o EC9841AS Nitrogen Oxides Analyzer PN 98415200 100 This instrument is manufactured by Ecotech P L in Australia and support the new SMD Microprocessor Board Part number 98000063 4 This manu
33. ic startup routine is replaced by a quick start routine The analyzer is returned to its last known operating parameters and normal operation is immediately restored This allows the analyzer to rapidly return to measurement mode and keeps data loss to a minimum If power is lost for greater than two minutes a full automatic restart is performed 2 2 2 Measure Modes The EC9841AS is a continuous measurement stream switch device It is constantly switching the measurement stream between NO and NO channels at six second intervals In addition approximately every 120 seconds the auto zero background routine is performed The current measurement channel can be observed on the main display The following modes will be displayed 98417601 AS Rev C CHAPTER 2 THEORY OF OPERATION NO SAMPLE FILL CELL FILLING WITH NO SAMPLE NO SAMPLE MEASURE NO MEASUREMENT IN PROCESS NOX SAMPLE FILL CELL FILLING WITH NOX SAMPLE NOX SAMPLE MEASURE NOX MEASUREMENT IN PROCESS BACKGROUND FILL CELL PURGING SAMPLE FOR AUTO ZERO BACKGROUND MEASURE AUTO ZERO MEASUREMENT IN PROCESS BACKGROUND PURGE CELL PURGING ZERO SAMPLE A full measurement cycle consists of both the NO and NO measurement routines After each full measurement cycle the two resultant measurements are processed to determine NO and
34. ications for various parameters that are continually monitored These parameters must be within acceptable operating ranges in order to display pass If FAIL is indicated this indicates a major failure in the affected area If the instrument is in startup mode START will be displayed 98417601 AS Rev C CHAPTER 4 TROUBLESHOOTING Note The sysTEM FAULTS screen only indicates a PASS Or FAIL for the various analyzer parameters and is meant to indicate major failures Desired operating ranges are indicated in the INSTRUMENT STATUS and SYSTEM TEMPERATURE ranges section If analyzer readings are not within these ranges it could indicate deterioration of certain assemblies within the analyzer or minor failures The following table lists the possible system fault messages that are displayed on the primary screen if a major failure occurs If a fault message is displayed use the Troubleshooting Guide to find the possible cause of the fault System Faults Screen Message Description Failure Limits OUT OF SERVICE Indicates the Service switch is in the OFF position Unless the analyzer is being serviced this switch should be in the IN position ZERO FLOW Indicates that the sample flow is less than 0 1 slpm COOLER FAILURE Indicates that the cooler temperature or voltage is not
35. ified to suit specific operating conditions It is recommended that this schedule be followed in order to maintain reliable long term operation of the analyzer Interval Weekly Monthly 3 Monthly 6 Monthly 1 Year 2 Year Item Procedure Section Inlet Particulate Filter Check Replace Service Manual 3 3 1 Event Log System Faults Service Manual 4 2 3 amp 4 2 6 Operation Manual 2 4 Service Manual 3 3 3 Operation Manual 2 4 Operation Manual 2 3 3 Service Manual 4 2 4 Operation Manual 3 8 Service Manual 3 3 7 Service Manual 3 3 4 Operation Manual 3 2 Service Manual 3 3 5 Service Manual 3 3 6 Service Manual 3 3 11 Clean Reaction Cell Clean Service Manual 3 3 9 Suggested intervals for normal operation and actual intervals will vary depending upon application The user can refer to this table as a guideline but should develop a maintenance schedule to suit their specific requirements Humid conditions nay necessitate more frequent replacement 18 98417601 AS Rev C CHAPTER 3 MAINTENANCE 3 2 Replaceable Parts EC9841AS Analyzer Spare Parts Requirements Description Part Number Filter sintered 3 required 002 024900 Filter unit disposable 036 040180 O ring orifice and filter 3 required 250004 19 3 Desiccant 5 gram pack 4 required 26000260 Charcoal activated 2 pound bulk container 850 056500 Filter element 5 micron consumable 50
36. ight accumulate pollens and dust Man made environmental changes such as construction dust might indicate more frequent change or a climate where dry dusty conditions are normal might dictate more frequent filter replacement than climates with few natural pollutants Determining the schedule for changing the filter is best developed by monitoring the filter at weekly intervals for the first few months then adapting the schedule to fit the specific site 3 3 2 Particulate Filter Replacement Procedure A Series Use Figure 9 as reference when performing the filter replacement procedure 22 98417601 AS Rev C CHAPTER 3 MAINTENANCE Figure 9 Particulate Filter Replacement 1 Open the front panel to access the service switches and particulate filter Disconnect the external pump 2 Completely unthread the filter cap by turning it counterclockwise 3 Pull the filter plunger out of the body carefully resting it in a secure place The O ring and filter membrane are now exposed inside the filter body 4 Remove inspect and wipe down the O ring Replace the O ring only if damaged 5 Remove discard and replace the old filter membrane 6 Reinstall the O ring over the new membrane reinstall the plunger and hand thread the cap back into place by turning it clockwise Do not use tools 7 Return the Pump to ON 8 Close the front panel 3 3 3 Clean Fan Filter The fan filter is located on the rear of th
37. ld be the gas pressure Set this value as PRESSURE 1 LOW in the PRESSURE CALIBRATION MENU and press Enter gt J Disconnect the pressure transducer from the measurement cell inlet and reconnect the Oy inlet tubing Press Reset on the analyzer secondary panel From the T EST M ENU select OZONATOR ON The flow calibration must now be completed 98417601 AS Rev A Figure 17 Pressure Calibration 37 EC9841AS NOx ANALYZER SERVICE MANUAL 3 5 3 Flow Calibration 1 From the HIDDEN MENU select the FLOW CALIBRATION MENU The menu of Figure 18 should be displayed FLOW CALIBRATION MENU CRITICAL ORIFICE 0 640 VALVE SEQUENCING ON AMBIENT PRESSURE 750 0 TORR GAS PRESSURE 250 0 TORR GAS FLOW 0 640 SLPM Figure 18 Flow Calibration Menu for ISO flow block 2 Set the CRITICAL ORIFICE to 0 640 and press Enter gt 3 Press Reset on the analyzer secondary panel 4 The actual flow should now be checked by turning on the pump and connecting a flow meter to the sample inlet of the analyzer The flow should read approximately 0 64 slpm If the flow is too low perform the sintered filter orifice replacement procedure If flow is too high there is probably a leak 3 6 Preprocessor ID Entry This procedure is only required if the microprocessor is not reading the device ID from the preprocessor board or if the preprocessor board has been replaced 1 From the HIDDN MENU set the SERI
38. ll also provide information as to the portion or component of the instrument which is at fault Message SERVICE SWITCH ACTIVATED RAM CHECKSUM FAILURE EAROM X DATA ERROR Y LCD DISPLAY BUSY Event Log Messages Description Checksum of memory at power down differs from checksum at power up Action Battery failure or system software error If error persists call Ecotech Customer Service for instructions Check Pressure PCA cable connections and Pressure PCA Unit taken out of service from Return analyzer to service front panel using the front panel switch LCD constantly busy Check display cable indicates hardware failure in connection Display PCA and display Microprocessor PCA EAROM designated X detected error at location Y SYSTEM POWER RESTORED LIMIT A D CONVERSION SYSTEM POWER FAILURE Power removed from system No action required HIGH VOLTAGE POT Power applied to system No action required High voltage adjustment Check PMT or High Voltage Module See the Troubleshooting Section exceeds range ERROR Analog to Digital converter Hardware failure in analog interface Replace the Microprocessor Board returning busy status 98417601 AS Rev C CHAPTER 4 TROUBLESHOOTING Message ERO FLOW N PAN RATIO lt 0 75 n SPA
39. ll cleaming ccecesseesseeseeeeeeseeeeeeeees 29 Reaction Cell Cleaning illustration o oo 30 Replaceable partS oonconcnnnnnnonnonnnocnnononononancnncconocnnos 19 Routine Maintenance ccocooccoconononcconnnonnnoconnciononinnnoo 21 Routine Maintenance Components illustration 22 i EC9841AS NOx ANALYZER SERVICE MANUAL S Scrubber maintenance ococoncccocnnonnnoncnonconoconocnnccnnonnss 24 Sensor module ies sscsessesiesecsessseneesieasvessasvonssedesseaess 13 Serial POrt iia 7 11 Serial Pot sE 39 Service SWItCHES otsides tner enirn enedes 7 Sintered filter replacemMent oconccnnonicnocninconnnnnononnnn 24 Sintered Filter Orifice Removal illustration 25 Span measure mode coocooococcconconnnonnnoncnnnconoconocnnocnnonnos 17 Spare A i i SEA its 19 Startup Mod s ns iis meraensis 16 System Faults display ooooooccnnccnonncncnonconcononanancnnnnn 47 System Temperatures and Tolerances illustration 47 System Temperatures SCreen 0 eee eee esses ese eeee 47 T TCI Piny latas 11 ii Theory of operation ssesseeeseseeesesrsrsrsreerererrsesrsreerees 9 Thermoelectric cooler CirCUit ooooonononcccnonancconnnnnos 16 TroubleshootiN8 ccononconocncncononononcnnonncnncnnonacnnos 43 50 U USB iaa 11 19 V Valve manifold uessa un ansni ense 15 Valve Test Menu Arnii aen iaeei 44 Valve Test Menu illustration oococoonnononcconnninnos 45 Voltage Regulator boalrd ooooo
40. lose button is enabled as shown below and the Analyzer is operating as usual again W Firmware Update Connect to Analyser Enter Bootloader OK Erase EAPROM OK Erase EEPROM SKIPPED Erase RAM SKIPPED Upload Firmware OK Verify Upload OK Run Firmware OK Previous Close Figure 22 Firmware Update completion screenshot 41 EC9841AS NOx ANALYZER SERVICE MANUAL 4 0 Troubleshooting 42 4 1 DC Power Supply Voltages Before consulting the troubleshooting section verify that the DC power supply voltages are present and within the specifications given for each printed circuit board listed in the following table Circuit board illustrations indicating test points and other component locations immediately follow the troubleshooting guide Troubleshooting Voltage Table PCB Supply DVM DVM Response Microprocessor 12V GOOD 5V 0 5V 10V 0 5V 20V 0 5V Voltage Reg TP7 AGND 12V 0 5V TP7 10V 0 5V TP7 10V 0 5V TP7 5V 0 25 Pressure TP1 AGND D2 Cathode 0 5V 0 25V TP1 U2 8 10V 0 5V TP1 U2 4 10V 0 5V Preprocessor 12V TP2 AGND J3 1 6 12V 0 5V 12V COOLER TP2 J1 9 12V 0 5V 12V CONVERTER TP2 J2 1 12V 0 5V 12 V MANIFOLD TP2 J2 5 12V 0 5V 12V 03 TP2 J2 9 12V 0 5V 5V TP2 J3 3 5V 0 25V 10V TP2 J3 4 10V 0 5V 10V TP2 J3 5 10V 0 5V 5VR TP2 J5 3 5V 0 25V The 12V GOOD test point is a 5 volt status output from the power supply to indicate that th
41. n in Figure 25 the fault or operational problem is probably related This is also true if one of the parameters is demonstrating a rapid change or is oscillating strongly around the desired setpoint For more information on the operational limits and fault messages refer to the table in section 4 2 7 System Faults 98417601 AS Rev A 45 EC9841AS NOx ANALYZER SERVICE MANUAL 46 GAS FLOW GAS PRESSURE AMBIENT PRESSURE 760 CONC VOLTAGE ANALOG SUPPLY DIGITAL SUPPLY k 5 2 HIGH VOLTAGE INSTRUMENT STATUS 0 765 375 4 5 12 2 660 VERSION 1 11 0002 Figure 25 Instrument Status Ranges 4 2 5 System Temperatures The SYST EM TI EMP ERATUR ES screen provides the reaction cell temperature the molycon temperature the chassis temperature the valve manifold temperature and the thermoelectric cooler temperature used to cool the PMT Figure 26 contains the nominal values which should be displayed on this screen If any of the parameters are outside the acceptable ranges a significant problem among these components is strongly indicated For more information on the operational limits and fault messages refer to the table in section 4 2 7 System Faults CELL TEMP SYSTEM TEMPERATURES 53 CONV TEMP 335 CHASSIS TEMP 40 MANIFOLD TEMP COOLER TEMP Figure 26 System Temperatures and Tolerances 4 2 6 System Faults The SYSTEM FAULTS display shows pass or fail ind
42. nd Accessories Part Number 98412021 KIT2 Description Manifold maintenance kit Reaction cell maintenance kit 98412027 KIT2 3 2 1 Expected Life Span of Consumables Component Minimum Typical Molycon 6 months 1 to 2 years 3 3 Maintenance Procedures Following is a list of routine maintenance procedures which may be required through the life of the analyzer Recommended equipment to perform maintenance Toolbox Oscilloscope Digital multimeter DMM Computer or remote data terminal and connection cable for RS232 communication Pressure transducer absolute and connection tubing calibrated in torr Flowmeter 2 slpm nominal Wire strippers Soldering iron Minifit extraction tool Orifice removal tool Assortment of 1 4 and 1 8 tubing and fittings Test zero air source Test span gas source Leak tester Q 00 n 000 000a0a0 0 00x _ 0 98417601 AS Rev A 21 EC9841AS NOx ANALYZER SERVICE MANUAL Figure 8 Routine Maintenance Components 3 3 1 Check Particulate Filter The inlet filter prevents particulates from entering the pneumatic components of the EC9841AS Contamination of the filter can result in degraded performance of the EC9841AS including slow response time erroneous readings temperature drift and various other problems Several factors affect the filter replacement schedule In the springtime for example the filter m
43. nts in the air it will begin to deposit a film on the walls and optical filter within the cell This will result in decreased sensitivity of the analyzer and increase the gain required to read NO The reaction cell should be cleaned periodically to remove deposits and restore sensitivity Caution Take extreme care not to damage the pressure transducer assembly on top of the reaction cell 98417601 AS Rev A 29 EC9841AS NOx ANALYZER SERVICE MANUAL 30 Warning After removal of power from the EC9841AS the exhaust should be maintained for approximately 15 minutes to purge the exhaust of ozone and prevent possible combustion of the charcoal Turn off the analyzer and disconnect the pump Disconnect the electrical and pneumatic fittings from the reaction cell remove the four screws that secure the cell to the PMT housing and remove the reaction cell from the PMT housing Refer to Figure 12 and remove the optical filter from the cell Clean the filter and the inside of the cell with high purity isopropyl alcohol and reassemble the cell Refer to Figure 12 and remove and replace the sintered filter from under the O inlet fitting Be sure to use new O rings If desired the orifice can be removed and cleaned or replaced Reassemble the reaction cell in reverse order of the above steps Recalibrate the analyzer refer to the EC9841AS Operation Manual Figure 12 Reaction Cell Cleaning 98417601 AS Rev C 3 3 10 Pre
44. of the Ecotech Microprocessor board SMD version provide provisions for a hidden menu This enables the experienced user to access menus for maintenance purposes These menus eliminate the need for a portable computer to perform flow amp pressure calibrations To access the hidden menu simultaneously press three keys on the front panel from the primary screen as follows Up arrow A lt Pg Up gt and Enter gt J The following menu will be displayed HIDDEN MENU SERIES S ANALYZER TYPE 9841 SUB TYPE STANDARD FLOW BLOCK TYPE ISO GAS NAME ous PRESSURE CALIBRATION MENU FLOW CALIBRATION MENU Figure 14 Hidden Menu SERIES Allows the user to choose the correct series of analyzer The options are A B amp s The selection must reflect the Hardware to which it is being installed i e for a 9841AS analyzer it must be set to s in order to operate correctly The s option is reserved for special system software ANALYSER TYPE Allows the user to choose the correct analyzer type The options are 9810 9811 9812 9820 9830 9841 9842 amp 9850 The selection must reflect the Hardware to which it is being installed 1 e for an EC9841AS analyzer it must be set to 9841 in order to operate correctly The analyzer type will default to gt if the device type has not been set or cannot be read from the preprocessor board SUB TYPE Allows the user to set the correct Hardware options for this analyzer The options for th
45. of the potentiometer settings is somewhat arbitrary and differences in the examples shown here and the values displayed on an operating instrument should not be construed as a definite indicator of a problem PREPROCESSOR POTS INPUT 40 TEST MEASURE 0 HIGH VOLTAGE ADJUST 53 NO 0 20 PPM CONC VOLTAGE 0 1 4 5 VOLTS HIGH VOLTAGE 600 700 VOLTS Figure 23 Preprocessor Pots Menu 4 2 2 Valve Test Menu The VALVE TEST MENU displays the current status of each valve in the instrument This menu can be particularly useful in correcting flow problems in the machine The valves can be opened and closed from this menu thus allowing the operator to determine whether valves are operating correctly Valve sequencing must be ON in order for correct gas measurement to be accomplished Refer to the EC984 AS Operation Manual for a key to the valve names used in the menu 98417601 AS Rev A 43 EC9841AS NOx ANALYZER SERVICE MANUAL 44 4 2 3 Event Log VALVE TEST MENU OPEN CLOSED CLOSED OPEN CLOSED OPEN CLOSED CLOSED VALVE 1 VALVE 2 VALVE 3 VALVE 4 VALVE 5 MEASURE ZERO GAS SPAN GAS INT INT INT INT INT EXT EXT EXT VALVE SEQUENCING ON Figure 24 Valve Test Menu Upon noting a possible operational problem examine the EVENT LOG menu to determine whether the microprocessor is reporting a system failure or problem Should the EVENT LOG indicate an error it wi
46. on turns on a small incandescent light bulb in the reaction cell The glow from this light simulates the glow of the normal chemilluminescent reaction of NO in the cell which is then detected by the PMT as if it were an actual signal This test is used to verify the operation of the PMT preamp and preprocessor measurement channel 4 3 2 Preamp The preamp test function generates an electronic test signal which is applied to the input of the PMT preamp This simulates an input from the PMT and is then processed as if it were an actual signal This test is used to verify the operation of the preamp and preprocessor isolated from the PMT 4 3 3 Electric The electric test function generates an electronic test signal which is applied to the input of the preprocessor This simulates an input to the preprocessor and is then processed as if it were an actual signal This test is used to verify the operation of the preprocessor PCA measure channel isolated from the PMT and preamp 4 3 4 Use of Diagnostic Modes The diagnostic modes are actuated by selecting DIAGNOSTIC MODE OPTIC or PREAMP Or ELECTRIC and adjusting the test measure potentiometer until a response simulated concentration is noted Response to tests will vary depending upon individual analyzer parameters These tests are typically pass fail Functional problems can be isolated to a single component by logical use of the diagnostic modes 48 98417601 AS Rev C CH
47. onnnconncccnonncocccconnnconnnon 11 Z Zero measure mode cccececeeeessscecececeesenteceeeeeeeees 17 98417601 AS Rev C
48. ontained unit housed in a steel case It is designed to meet UL VDE CSA and other regulatory requirements It converts 99 to 264 VAC 50 60 Hz to 12 VDC power for distribution within the analyzer The power supply also furnishes a 250 msec power extension in the event of power failure to allow the computer to store data before the power failure can affect it 2 1 1 2 Voltage Regulator The voltage regulator board regulates and distributes the different voltages needed throughout the system 12 VDC to 5 VDC for the digital circuitry and 12 VDC to 10 v for analog circuitry An additional 15 VDC supply is present to power the microprocessor display supplies and analog output circuits The voltage regulator also furnishes a 300 msec power extension in the event of power failure to allow the computer to store data before the power failure can affect it 2 1 1 3 Microprocessor The microprocessor board contains a battery backed clock calendar and an onboard 16 bit microprocessor MC68HC12 operating at 16MHz The microprocessor board is the control center for input and output apparatus such as the 2 inch by 4 inch liquid crystal display LCD keyboard switches the serial ports and the 50 pin I O connector on the rear panel The 50 pin I O connector input accepts control lines from the rear panel and sends status and failure signals to solid state relay drivers Support circuitry for the liquid crystal display includes a 20 V power supply and digit
49. ration or validity of the data obtained from the analyzer When the Service switch is set from OUT to IN the instrument returns to the normal operating conditions 1 1 3 Inspect the Components Verify that the components were not damaged in shipping If any PC boards are dislodged or cables disconnected follow the instructions below 98417601 AS Rev A 7 EC9841AS NOx ANALYZER SERVICE MANUAL 1 1 4 Reinsert Dislodged Boards The bottom edge of the boards must be held in place by the guides The top of the boards must be attached to the metal bulkheads by the plastic or metal studs with spring tips 1 1 5 Cable Connections The cable connectors and the board connectors must be matched securely in place for correct connection The red indicator on each cable must be positioned at the arrowhead mark on the board connector Make the connection by pressing the cable connector into the mating connector until a click is heard Then fold the retainers inward to secure the connection see Figure 3 Figure 3 Cable Connections 8 98417601 AS Rev C CHAPTER 2 THEORY OF OPERATION 2 0 Theory of Operation The EC9841AS analyzer uses gas phase chemilluminescence detection to perform continuous analysis of nitric oxide NO total oxides of nitrogen NO and nitrogen dioxide NO The EC9841AS design represents an advance in nitrogen oxides analysis technology achieved primarily by using adaptive microprocessor control of a single measurement
50. rator unit If unfamiliar with the ozone generator refer to figure 8 in the service manual o This unit generates Ozone for this reason the exhaust pump must be connected through a charcoal scrubber to remove excess ozone o Surfaces marked with a Caution Hot Surface see internationally recognized symbols on page 4 sticker may get hot and deliver burns Measure the tempera ture on the surface before making any contact with it Equipment Rating o 100 120 220 240V 10 o 50 60 Hz o 250 VA max o FUSE 5 3 15A T 250V o All wiring must be in accordance with local norms and be carried out by experi enced personnel 98417601 AS Rev C Service and Spare Parts 98417601 AS Rev C FRONT MATTER For world wide customer service amp spare parts contact ECOTECH Address Phone Fax Email Service Email Spare Parts Web Ecotech Pty Ltd 1492 Ferntree Gully Rd Knoxfield Australia VIC 3180 61 1300 364 946 61 1300 669 763 ecotech O ecotech com au partsO ecotech com au www ecotech com au EC9841AS NOx ANALYZER SERVICE MANUAL 1 0 Installation 1 1 Initial Check Verify that the serial number label on the documentation and the serial number s on the analyzer match Check to make certain your instrument arrived undamaged If you find damage report it as described in the preface on the page titled Claims for Damaged Shipments and Shipping Discrepancies in the Operation manual Anal
51. shing on the Microprocessor Board Check Display connection Replace the Microprocessor or Preprocessor PCA The problem could exist in the PMT or in the PMT housing assembly Consult the factory for further service 1 Check J5 connector on Microprocessor 2 Check J6 connector on Preprocessor 3 Reprogram device ID 4 Replace Preprocessor 98417601 AS Rev A 51 INDEX A AZS cycle Mode csroscoincnoieorcn coseno in sein 17 B Block diagram ceecceesceeceeseeeeeeeeeceseceeeeeeeneeeeeees 13 C Cable Connections illustration ooooooocconncconcconos 8 Charcoal scrubber maintenance oooooccccnnnocnnononanon no 24 Cooler replace Ment ooononncnnccnonnconoconoconocnonnnonnncnnnnns 27 Cooler Replacement lustratiOM oooconcnn 29 D Data Lon tito 46 DECI aaa 16 Delay loop iii irene iccien 14 Desiccant pack replacement ooooononccnnnnonoconnnncncnncnnos 26 DFU replacement cooooconncniccnncnconoconoconoconocononnninnninnanns 24 Diagnostic modes cccceecceesceeeeeteceeeeeeeeneeeneeeneees 48 E Electric test functi0N ocoooconnnonoccnonancccononnnononnnncnono 49 Event Log E RAT 45 F Fan filter Cleaming cecceeeesececececeeeeeeeeneeeneeeeeees 23 Filter maintenance ooooocccnononnnononncconanacononanononnnnnonos 22 Flow Diagram illustration oooonconcnncnnnonnccnncncnnnnns 10 Flow Pressure board calibration 33 34 I Illustration
52. ssure Transducer Handling CHAPTER 3 MAINTENANCE The pressure transducers used in the EC9841AS require careful handling The following precautions should be taken when removing or installing the transducers T pE Figure 13 Pressure Transducer Replacement 1 Never touch the sensing face of the transducer the recessed face opposite the cable connection 2 Never remove the transducers by pulling on the plastic bodies Always grasp the transducers by the metal ring at the base of the plastic housing 3 Remove and reinstall the transducers by gently twisting them in or out of their mounting sockets Do not force them in or out 4 Do not place excess force on the electrical cable s connection to the transducer 98417601 AS Rev A 31 EC9841AS NOx ANALYZER SERVICE MANUAL 5 After a transducer is replaced the pressure PCA should be recalibrated Refer to section 3 5 3 3 11 Leak Test Procedure This is a test for the pneumatic system of the instrument The display readings will indicate whether the system is leaking or not Note This procedure applies only to the instrument It does not include the EZS valve option The option if included in the instrument must be disabled to perform this test 1 Enter the TEST MENU select the OUTPUT TEST MENU then select VALVE TEST MENU from these items pick VALVE SEQUENCING and set to OFF 2 Plug the Inlet port on th
53. t light reaches its window Turn off analyzer power and the pump Remove the Rx cell PMT housing assembly from the analyzer Remove the desiccant access cap and disconnect the electrical connector Remove the 12 screws that secure the PMT housing cover to the heatsink and lift the cover off the heatsink It may be necessary to loosen the crossbar or mounting bracket to remove the PMT housing cover Disconnect the HVPS preamp from the PMT and remove the PMT from its housing Refer to Figure 11 Important Note the orientation of the red and black cooler wires as they relate to the PMT housing heatsink The new cooler must be installed in the same way From the underside of the heatsink remove the two screws that secure the PMT cold block to the heatsink and remove the cold block Refer to Figure 11 Remove the cooler from the heatsink and disconnect the cooler from the electrical connector Note If corrosion or moisture is detected inside the PMT housing assembly reduce the desiccant replacement interval replace the desiccant more often 27 EC9841AS NOx ANALYZER SERVICE MANUAL 28 10 11 12 13 14 15 Reassemble the Rx cell PMT housing and reinstall in the analyzer Clean the cooler facings of the heatsink and PMT cold block and recoat with a thin layer of heatsink compound Dow Corning 340 or equivalent Install the new cooler in place on the PMT housing being careful to align it in the notch on the
54. tant flow and optimum instrument measurement The nature of the chemilluminescent reaction requires a strong vacuum be present in the reaction cell for satisfactory measurement 2 1 2 2 Optics Chemilluminescent reaction between NO and O emits broad band radiation This radiation is passed through the optic filter to the photomultiplier tube PMT The PMT detects the radiation and converts it to a current which is directly proportional to the chemilluminescent intensity Reaction Cell The cell is designed to optimize signal to noise ratio Its size gas mixing scheme and shape are optimized specifically for the side on PMT The reaction cell is heated and controlled to approximately 50 C The reaction cell also contains the ozone flow orifice and the pressure transducer which measures cell pressure Optical Bandpass Filter The colored glass optical filter limits the light reaching the PMT to the frequency of interest for the NO reaction Photomultiplier Tube PMT The cooled PMT detects an amount of light proportional to the concentration of NO present in the measurement cell The PMT is connected to an integrated high voltage power supply HVPS preamp 2 1 2 3 Electronics 98417601 AS Rev A o Preprocessor The preprocessor contains circuitry to amplify low level DC from the photomultiplier PMT preamp a PMT high voltage control a thermal electric TE cooler control circuit two heater control circuits Rx cell and moly
55. within the acceptable limits A fault is indicated if the cooler temperature is above 15 C or below 0 C 12 VOLT SUPPLY Indicates that the 12 volt supply voltage is not within the acceptable FAILURE limits A fault is indicated if the 12 volt supply voltage is below 11 1 volts or above 14 3 volts HIGH VOLTAGE Indicates that the high voltage is not within the acceptable limits A FAILURE fault is indicated if the high voltage reading differs by greater than 25 of the expected value as determined from the high voltage pot setting CELL TEMPERATURE Indicates that the cell temperature is not within the acceptable limits FAILURE A fault is indicated if the cell temperature is below 35 C or above 60 C CONVERTER Indicates that the converter temperature is not within the acceptable TEMPERATURE limits A fault is indicated if the converter temperature is below ici 250 C or above 350 C VALVE MANIFOLD Indicates that the valve manifold temperature is not within the TEMPERATURE acceptable limits A fault is indicated if the valve manifold FAILURE temperature is below 45 C or above 65 C START UP Indicates that the analyzer is in start up mode Usually after power SEQUENCE ACTIVE up or reset 4 3 Test Functions The following lists the available diagnostic modes in the EC9841AS under the TEST MENU 98417601 AS Rev A 47 EC9841AS NOx ANALYZER SERVICE MANUAL 4 3 1 Optic The optic test functi
56. yzers are shipped ready to power up Occasionally however rough handling during shipment causes dislodged PC boards disconnected cables or incorrectly positioned switches Verify that your instrument is in operating condition by performing the following procedure 1 1 1 Remove the Top Cover Grasp the front top corners of the front panel and pull forward The panel will pop loose and pivot forward See Figure 1 The top cover retaining hardware is then visible as shown in Figure 2 Use a screwdriver to unscrew the two captive screws When the two captive screws are loosened slide the cover backward about 4 inches and lift the top cover straight up GRIP GRIP HERE HERE PD GEN Bled Clos Pa TA Figure 1 Opening the Front Panel 6 98417601 AS Rev C CHAPTER 1 INSTALLATION PARTICULATE FILTER Captive screws SAMPLE DELAY INTERNAL PUMP CHARCOAL SECONDARY COIL HOUSING VERSION CANISTER PANEL Figure 2 The Secondary Panel 1 1 2 Service Switch Opening the front panel allows a view of the secondary panel where four switches are visible The position of the toggle switches for operating mode is DC PowerON Pump ON Service IN The Reset switch is not a toggle switch and is only activated when pressed It resets the microprocessor When in the OUT position the Service switch sets the OUT OF SERVICE bit in the 50 pin I O interface and in the status word from the serial port The OUT position has no other effect on the ope
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