Teledyne API – Model T700 Dynamic Dilution Calibrator
xv
9.4.8. Valve Driver PCA................................................................................................................................ 255
9.4.9. Input Gas Pressure / Flow Sensor Assembly ..................................................................................... 256
9.4.10. PHOTOMETER O3 Generator Pressure/FLOW SENSOR Assembly ............................................. 257
9.4.11. Motherboard...................................................................................................................................... 258
9.4.11.1. A/D Functions ............................................................................................................................ 258
9.4.11.2. Test Channel / Analog Outputs Voltage.................................................................................... 258
9.4.11.3. Status Outputs........................................................................................................................... 260
9.4.11.4. Control Inputs ............................................................................................................................ 261
9.4.11.5. Control Outputs ......................................................................................................................... 261
9.4.12. CPU .................................................................................................................................................. 262
9.4.13. The Calibrator Doesn’t Appear on the Lan or Internet...................................................................... 262
9.4.14. RS-232 Communications.................................................................................................................. 263
9.4.14.1. General RS-232 Troubleshooting.............................................................................................. 263
9.4.14.2. Troubleshooting Calibrator/Modem or Terminal Operation....................................................... 263
9.4.15. Temperature Problems ..................................................................................................................... 264
9.4.15.1. Box / Chassis Temperature....................................................................................................... 264
9.4.15.2. Photometer Sample Chamber Temperature ............................................................................. 264
9.4.15.3. UV Lamp Temperature.............................................................................................................. 264
9.4.15.4. Ozone Generator Temperature ................................................................................................. 265
9.5. TroubleShooting the Optional O
3
Photometer .......................................................................................... 265
9.5.1. Dynamic Problems with the Optional O3 Photometer ........................................................................ 265
9.5.1.1. Noisy or Unstable O
3
Readings at Zero ...................................................................................... 265
9.5.1.2. Noisy, Unstable, or Non-Linear Span O
3
Readings .................................................................... 266
9.5.1.3. Slow Response to Changes in Concentration............................................................................. 266
9.5.1.4. The Analog Output Signal Level Does Not Agree With Front Panel Readings........................... 266
9.5.1.5. Cannot Zero................................................................................................................................. 266
9.5.1.6. Cannot Span................................................................................................................................ 266
9.5.2. Checking Measure / Reference Valve ................................................................................................ 267
9.5.3. Checking The UV Lamp Power Supply .............................................................................................. 268
9.6. TroubleShooting the Optional O
3
generator.............................................................................................. 269
9.6.1. Checking The UV Source Lamp Power Supply.................................................................................. 269
9.7. Service Procedures................................................................................................................................... 270
9.7.1. Disk-On-Module Replacement Procedure.......................................................................................... 270
9.8. Technical Assistance ................................................................................................................................ 270
9.9. Frequently Asked Questions (FAQs) ........................................................................................................ 271
10. PRINCIPLES OF OPERATION....................................................................................... 273
10.1. Basic Principles of Dynamic Dilution Calibration.................................................................................... 273
10.1.1. Gas Phase Titration Mixtures for O3 and NO2................................................................................. 275
10.2. Pneumatic Operation .............................................................................................................................. 276
10.2.1. Gas Flow Control .............................................................................................................................. 277
10.2.1.1. Diluent and Source Gas Flow Control ....................................................................................... 277
10.2.1.2. Flow Control Assemblies for Optional O
3
Components ............................................................ 278
10.2.1.3. Critical Flow Orifices.................................................................................................................. 279
10.2.2. Internal Gas Pressure Sensors......................................................................................................... 280
10.3. Electronic Operation ............................................................................................................................... 281
10.3.1. Overview ........................................................................................................................................... 281
10.3.2. CPU .................................................................................................................................................. 282
10.3.2.1. Disk-on-Module (DOM).............................................................................................................. 283
10.3.2.2. Flash Chip ................................................................................................................................. 283
10.3.3. Relay PCA ........................................................................................................................................ 284
10.3.3.1. Valve Control ............................................................................................................................. 285
10.3.3.2. Heater Control ........................................................................................................................... 285
10.3.3.3. Relay PCA Status LEDs & Watch Dog Circuitry ....................................................................... 285
10.3.3.4. Relay PCA Watchdog Indicator (D1)......................................................................................... 286
10.3.4. Valve Driver PCA.............................................................................................................................. 287
10.3.4.1. Valve Driver PCA Watchdog Indicator ...................................................................................... 287
10.3.5. Motherboard...................................................................................................................................... 288