Tp 15: Fid Reduced Sensitivity - ABB PGC2000 Operation And Service Manual

2. Gently move or touch coaxial cable, while monitoring detector output on recorder. Some
movement of signal is normal, but spikes of noise should not occur.
3. If noise spikes are systematically generated, check the coaxial cable connections.
4. If the connections are correct and tight, replace coaxial cable.

TP 15: FID REDUCED SENSITIVITY

It is the customer's responsibility to ensure that the area is safe and and hazard-
free, and will remain so the entire time the analyzer is open. This responsibility
includes ensuring adequate ventilation in analyzer shelter and obtaining proper
work permits, etc.
See "AIR PURGING" in Section 4 for the override function. Do not perform
override until you have read Section 4 completely and you understand and can
perform the procedure requirements.
1. Stop analysis at the end of the current cycle and make no sample injection until the procedure is
complete.
2. Check analyzer attenuation in Manual Control Mode. Perform Test Procedure 30 (Checking
Temperature Table Values), steps 1 and 2.
3. Verify sufficient sample flow to sample system.
4. Verify sample valve is functioning correctly.
5. Check to ensure correct carrier type: Helium, Nitrogen, etc.
6. Verify correct sample valve ON and OFF times in method table. Perform Test Procedure 33
(Checking Method Table Configuration).
7. Refer to the application data sheet supplied with your chromatograph and check carrier, makeup
gases particularly splitter flow, and make any necessary adjustments.
8. If significant corrections were made in steps 2 through 7, run a single cycle analysis to determine
if sensitivity has improved. If sensitivity is now satisfactory, Test Procedure 16 is complete. If
sensitivity is still reduced, continue to step 9.
9. Verify detector gain jumper installed correctly.
10. Perform Test Procedure 28 (FID Polarizing Voltage Test). If sensitivity is normal, Test
Procedure 15 is complete. If sensitivity continues to be reduced, continue to step 11.
11. Clean FID as described in "FID REPAIR/Cleaning the Collector" in Section 8.
12. Apply power and gases to analyzer. After temperature stabilizes, check sensitivity. If
satisfactory, Test Procedure 15 is complete. If not, perform steps 13 through 15.
13. Replace electrometer and repeat step 12.
14. Replace coaxial cable and repeat step 12.
15. Replace FID and repeat step 12.
2000-OSM, F1
CAUTION
7-7