Table of ContentsTeledyne API – Model T300/T300M CO Analyzer
Teledyne Analytical Instruments xiv
12.4.2. Excessive Noise .................................................................................................................................270
12.5. Subsystem Checkout ...............................................................................................................................271
12.5.1. AC Mains Configuration .....................................................................................................................271
12.5.2. DC Power Supply ...............................................................................................................................271
12.5.3. I
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C Bus ...............................................................................................................................................272
12.5.4. Touchscreen Interface .......................................................................................................................272
12.5.5. LCD Display Module ..........................................................................................................................272
12.5.6. Relay Board .......................................................................................................................................272
12.5.7. Sensor Assembly ...............................................................................................................................273
12.5.7.1. Sync/Demodulator Assembly .....................................................................................................273
12.5.7.2. Electrical Test .............................................................................................................................274
12.5.7.3. Opto Pickup Assembly ...............................................................................................................274
12.5.7.4. GFC Wheel Drive .......................................................................................................................274
12.5.7.5. IR Source ....................................................................................................................................275
12.5.7.6. Pressure/Flow Sensor Assembly ...............................................................................................275
12.5.8. Motherboard .......................................................................................................................................276
12.5.8.1. A/D Functions .............................................................................................................................276
12.5.8.2. Test Channel / Analog Outputs Voltage .....................................................................................276
12.5.8.3. Analog Outputs: Current Loop ....................................................................................................278
12.5.8.4. Status Outputs ............................................................................................................................278
12.5.8.5. Control Inputs – Remote Zero, Span ..........................................................................................279
12.5.9. CPU ....................................................................................................................................................279
12.5.10. RS-232 Communications .................................................................................................................279
12.5.10.1. General RS-232 Troubleshooting .............................................................................................279
12.5.10.2. Troubleshooting Analyzer/Modem or Terminal Operation .......................................................280
12.5.11. The Optional CO
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Sensor ................................................................................................................280
12.6. Repair Procedures ...................................................................................................................................281
12.6.1. Repairing Sample Flow Control Assembly ........................................................................................281
12.6.2. Removing/Replacing the GFC Wheel ................................................................................................282
12.6.3. Checking and Adjusting the Sync/Demodulator, Circuit Gain (CO MEAS) ......................................284
12.6.3.1. Checking the Sync/Demodulator Circuit Gain ............................................................................284
12.6.3.2. Adjusting the Sync/Demodulator, Circuit Gain ...........................................................................285
12.6.4. Disk-On-Module Replacement ...........................................................................................................286
12.7. Frequently Asked Questions ...................................................................................................................287
12.8. Technical Assistance ...............................................................................................................................288
13. THEORY OF OPERATION .............................................................................................. 289
13.1. Measurement Method ..............................................................................................................................289
13.1.1. Beer’s Law .........................................................................................................................................289
13.2. Measurement Fundamentals ...................................................................................................................290
13.2.1. Gas Filter Correlation .........................................................................................................................291
13.2.1.1. The GFC Wheel ..........................................................................................................................291
13.2.1.2. The Measure Reference Ratio ...................................................................................................292
13.2.1.3. Summary Interference Rejection ................................................................................................294
13.3. Flow Rate Control ....................................................................................................................................295
13.3.1.1. Critical Flow Orifice .....................................................................................................................295
13.3.2. Particulate Filter .................................................................................................................................296
13.3.3. Pneumatic Sensors ............................................................................................................................297
13.3.3.1. Sample Pressure Sensor ...........................................................................................................297
13.3.3.2. Sample Flow Sensor ..................................................................................................................297
13.4. Electronic Operation ................................................................................................................................297
13.4.1. CPU ....................................................................................................................................................299
13.4.1.1. Disk-On-Module (DOM) ..............................................................................................................299
13.4.1.2. Flash Chip ..................................................................................................................................299
13.4.2. Optical Bench & GFC Wheel .............................................................................................................300
13.4.2.1. Temperature Control ..................................................................................................................300
13.4.2.2. IR Source ....................................................................................................................................300