Table of Contents Teledyne API – Model T300/T300M CO Analyzer
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12.5.3. I2C Bus.............................................................................................................................................. 279
12.5.4. Touchscreen Interface...................................................................................................................... 280
12.5.5. LCD Display Module......................................................................................................................... 280
12.5.6. Relay Board ......................................................................................................................................280
12.5.7. Sensor Assembly.............................................................................................................................. 281
12.5.7.1. Sync/Demodulator Assembly.................................................................................................... 281
12.5.7.2. Electrical Test............................................................................................................................ 281
12.5.7.3. Opto Pickup Assembly ..............................................................................................................282
12.5.7.4. GFC Wheel Drive ...................................................................................................................... 282
12.5.7.5. IR Source................................................................................................................................... 282
12.5.7.6. Pressure/Flow Sensor Assembly .............................................................................................. 283
12.5.8. Motherboard...................................................................................................................................... 284
12.5.8.1. A/D Functions............................................................................................................................ 284
12.5.8.2. Test Channel / Analog Outputs Voltage.................................................................................... 284
12.5.8.3. Analog Outputs: Current Loop................................................................................................... 285
12.5.8.4. Status Outputs........................................................................................................................... 286
12.5.8.5. Control Inputs �� Remote Zero, Span......................................................................................... 286
12.5.9. CPU................................................................................................................................................... 287
12.5.10. RS-232 Communications................................................................................................................ 287
12.5.10.1. General RS-232 Troubleshooting............................................................................................ 287
12.5.10.2. Troubleshooting Analyzer/Modem or Terminal Operation ...................................................... 288
12.5.11. The Optional CO2 Sensor ...............................................................................................................288
12.6. Repair Procedures.................................................................................................................................. 289
12.6.1. Repairing Sample Flow Control Assembly ....................................................................................... 289
12.6.2. Removing/Replacing the GFC Wheel............................................................................................... 290
12.6.3. Checking and Adjusting the Sync/Demodulator, Circuit Gain (CO MEAS)..................................... 292
12.6.3.1. Checking the Sync/Demodulator Circuit Gain........................................................................... 292
12.6.3.2. Adjusting the Sync/Demodulator, Circuit Gain..........................................................................293
12.6.4. Disk-On-Module Replacement.......................................................................................................... 294
12.7. Frequently Asked Questions .................................................................................................................. 295
12.8. Technical Assistance.............................................................................................................................. 296
13. THEORY OF OPERATION.............................................................................................. 297
13.1. Measurement Method............................................................................................................................. 297
13.1.1. Beer’s Law ........................................................................................................................................ 297
13.2. Measurement Fundamentals.................................................................................................................. 298
13.2.1. Gas Filter Correlation........................................................................................................................ 299
13.2.1.1. The GFC Wheel......................................................................................................................... 299
13.2.1.2. The Measure Reference Ratio ..................................................................................................300
13.2.1.3. Summary Interference Rejection............................................................................................... 303
13.3. Flow Rate Control................................................................................................................................... 304
13.3.1.1. Critical Flow Orifice.................................................................................................................... 305
13.3.2. Particulate Filter................................................................................................................................ 306
13.3.3. Pneumatic Sensors........................................................................................................................... 306
13.3.3.1. Sample Pressure Sensor .......................................................................................................... 306
13.3.3.2. Sample Flow Sensor ................................................................................................................. 306
13.4. Electronic Operation............................................................................................................................... 306
13.4.1. CPU................................................................................................................................................... 309
13.4.1.1. Disk-On-Module (DOM)............................................................................................................. 309
13.4.1.2. Flash Chip ................................................................................................................................. 309
13.4.2. Optical Bench & GFC Wheel ............................................................................................................310
13.4.2.1. Temperature Control ................................................................................................................. 310
13.4.2.2. IR Source................................................................................................................................... 310
13.4.2.3. GFC Wheel................................................................................................................................ 310
13.4.2.4. IR Photo-Detector...................................................................................................................... 312
13.4.3. Synchronous Demodulator (Sync/Demod) Assembly ...................................................................... 312
13.4.3.1. Signal Synchronization and Demodulation ...............................................................................313
06864B DCN6314