Chromatography Forum

I work at a GC/MSD (6890/5973).
This system worked good, but yesterday that began to fail.
This is the error message in the Logbook:

1101, "[{REP} acq: strt sim]: Unrecoverable mass spec fault: 512"
Difficulty with the electromultiplier supply at runtime 6.94.

I noticed that after solvent delay the EM is on, then off, then on, then off, then on, and finally is off at 6.94 minutes.

The filament is good and the vacuum is good too. The EMV was 1500.

I executed Profile and Scan (in Manual Tune) and the error message is the same.

Help me please!

It may be a bad multiplier. How long has it been since you changed your multiplier? However, with the EMV only at 1500 it would appear that the multiplier is ok. If the multiplier is not the issue it sounds like a bad board somewhere, top board or main board.

If your voltage is 1500, the multiplier may be relatively new. Did you install this recently?

If the problem is intermittent, it could be an electrical contact. There are 3 gold-tipped wires associated with the multiplier and mount. Check these connections to see if they are loose, deformed, or what have you. Replace them if you can.

Can you post your other tune settings? And recent maintenance?