Varian GC 3800 ECD Signal Problem
Posted: Wed Mar 14, 2012 12:40 pm
The ECD signal saturates to 1V.
The DEFC was found defective. Repalced. Still no use.
The Column and Injector fittings are all OK.
Saturates to 1V in range 1.
Saturates to .7V in range 10 and slowly comes down.
Made auto zero and injected a sample. Peaks are OK.
Replaced Detector Pulse and signal cable assys.
Checked by replacing with another ECD PCB.
By the way this is a sudden developement on a working system.
Any suggestions please, for bringing down the Signal.
The DEFC was found defective. Repalced. Still no use.
The Column and Injector fittings are all OK.
Saturates to 1V in range 1.
Saturates to .7V in range 10 and slowly comes down.
Made auto zero and injected a sample. Peaks are OK.
Replaced Detector Pulse and signal cable assys.
Checked by replacing with another ECD PCB.
By the way this is a sudden developement on a working system.
Any suggestions please, for bringing down the Signal.