General Troubleshooting & Service Teledyne API T703/T703U Calibrator Operation Manual

166

TEST FUNCTION DIAGNOSTIC RELEVANCE AND CAUSES OF FAULT CONDITIONS.

PHOTO LAMP TEMP
Poor photometer temp control can cause instrument noise, stability and drift. Temperatures
outside of the specified range or oscillating temperatures are cause for concern.
Possible causes of faults are the same as PHOTO LAMP TEMP WARNING from Table 8-1
PHOTO SPRESS
The pressure of the gas in the photometer’s sample chamber is used to calculate the
concentration of O3 in the gas stream. Incorrect sample pressure can cause inaccurate
readings.
- Check for Gas Flow problems. See Section Table 8-1.
PHOTO STEMP
The temperature of the gas in the photometer’s sample chamber is used to calculate the
concentration of O3 in the gas stream. Incorrect sample temperature can cause inaccurate
readings.
Possible causes of faults are:
- Bad bench lamp heater
- Failed sample temperature sensor
- Failed relay controlling the bench heater
- Failed Relay PCA
- I
2C Bus malfunction
- Hot Lamp
PHOTO SLOPE
Values outside range indicate:
Contamination of the Zero Air or Span Gas supply.
Instrument is miss-calibrated.
Blocked Gas Flow.
Faulty Sample Pressure Sensor or circuitry.
Bad/incorrect Span Gas concentration.
PHOTO OFFSET Values outside range indicate:
Contamination of the Zero Air supply.
TIME
Time of Day clock is too fast or slow.
To adjust see Section 4.7.2.
Battery in clock chip on CPU board may be dead.

07223C DCN6572