Chromatography Forum

Hello folks,

I am having a problem with an old 5890/5972 GC/MS, using the MSD G1701BA software. When we start a run, the autosampler and the GC start correctly, but the electron multiplier does not turn on. We can view the PFTBA in tuning modes, but the EM will not turn on during data acquistion. Using a solvent delay makes no difference. The method is configured to use the MS in the inlet panel.

I have reinstalled the instrument in the configuration panel and am using a new tune file (I have heard of corrupted tune files), but it does not help. I think I have seen a similar issue come up on this board, but I cannot find anything useing the search.

I had a similar problem recently with our 5975 using a purge and trap. Turned out it was the Remote cable between the MS and the GC. I could either get the GC to run its program with no MS data or get the MS to acquire data while the GC would act like you pressed the stop button just as it started. Took me a week to figure that one out especially since that cable just lays behind the instrument and is never moved so I didn't imagine it could possibly go bad.

I wish I still have some of the old software setup here because I also remember there is some strange setting in there that can do the same thing, just don't remember exactly what it is or where it is without the software to poke around on.

Try setting up a method where the Sample Inlet is set to Other/None and Injection source is set to Immediate Start then start a blank run and see if the MS acquires data. If it does try replacing the Remote Cable.

There is a box that needs to be clicked, to have MS data be acquired. Then of course that can be saved with the Method.

I don't have this unit any longer, so can't remember exactly which window includes this. Try Edit Entire Method, try MS box in the window too.

It's in the Sequence setup; you have to make sure you tell the system that it is an on-line method and not an off-line method. Default for some weird reason is offline.

It sounds very much like a remote start cable/board issue to me. Unfortunately there is no handshaking, so the system blissfully runs without knowing whether or not the MS is actually turning on.

Thanks for the replies.

This issue went away as mysteriously as it arrived. About an hour after posting here, talking to Agilent, and contacting some other labs about it, the darn thing just started working with no additional intervention on my part. I think is was just my turn for the intrumentation to make a fool out of me. It will not be the last time.

Around here we call that a visit from the "fecal fairy". Run it off to another department as quickly as you can

If it happens again, I would definitely check the remote cable.