perkin elmer autosystem

[belen]

Hi all!

I´m using a Perkin Elmer autosystem for gas chromatography. When I press autozero buttom it gives me a value of 997.61mV althouth the flame doesn´t remain and it switches off inmediatedly.
Can anyone give me a hand with this?

I know its a very old machine but I really need help to solve it...

Thanks a lot in advance!!!

[CE Instruments]

Sounds like the automatic flame test level is set below the 1000mV auto zero level. Try auto zeroing before you ignite the FID, this should give you a high starting voltage when you auto zero. If this does not work you may have a value entered on the GC for flame out level, I have no idea if this is a feature of the PE GC because I have never used one.

[cbwhipp]

If your signal is reading 997 mV, then the FID is shorting out somewhere. Remove the the red wire that is connected to the FID body that is coming from the FID Amplifier board - make sure that you have -200 mV on this red cable, if not then your FID amp board is bad. If you have the -200, then you need to disassemble the FID and make sure all the parts are making the correct contact points, especially the clip that sits on the jet tip. You may have to replace the collector assembly: If the flame gases were running too Hydrogen rich for a period of time, then the collector may be trashed.