Thermo 42i - Page 8

Contents
viii Model 42i Low Source Instruction Manual Thermo Electron Corporation
Thermoelectric Cooler Fins Inspection and Cleaning..............5-4
Fan Filters Inspection and Cleaning........................................5-4
Pump Rebuilding....................................................................5-5
Chapter 6 Troubleshooting.............................................................................. 6-1
Safety Precautions ...................................................................6-1
Troubleshooting Guides..........................................................6-2
Board-Level Connection Diagrams .........................................6-6
Connector Pin Descriptions....................................................6-8
Service Locations...................................................................6-22
Chapter 7 Servicing.......................................................................................... 7-1
Safety Precautions ...................................................................7-3
Firmware Updates...................................................................7-5
Replacement Parts List............................................................7-5
Cable List................................................................................7-6
Removing the Measurement Bench and
Lowering the Partition Panel...................................................7-8
Pump Replacement...............................................................7-11
Fan Replacement...................................................................7-12
PMT Cooler and Reaction Chamber Assembly Replacement 7-13
Photomultiplier Tube Replacement ......................................7-15
PMT High Voltage Power Supply Replacement ...................7-16
PMT Voltage Adjustment.....................................................7-18
Reaction Chamber Cleaning or Removal ..............................7-19
NO
2
-to-NO Converter Replacement....................................7-21
Solenoid Valve Replacement .................................................7-23
Ozonator Assembly Replacement..........................................7-24
Ozonator Transformer Replacement .....................................7-26
Input Board Replacement .....................................................7-26
Input Board Calibration........................................................7-28
DC Power Supply Replacement ............................................7-29
Analog Output Testing .........................................................7-30
Analog Output Adjustment...................................................7-32
Pressure Transducer Assembly Replacement..........................7-33
Pressure Transducer Calibration ...........................................7-35
Temperature Control Board Replacement.............................7-37
Ambient Temperature Calibration ........................................7-37
Fuse Replacement .................................................................7-39
Scrubber Replacement...........................................................7-39
I/O Expansion Board (Optional) Replacement .....................7-40
Digital Output Board Replacement.......................................7-42
Motherboard Replacement....................................................7-42
Measurement Interface Board Replacement ..........................7-43