GCMS troubleshooting - episode 2

[The3dstickman]

Good morning,

Still fighting with this 5973......

This one has a diffusion pump, but cannot get it to turn on. I'm getting error #4; "Difficulty with Mass filter electronics".

Looked up the error, found that the following could be wrong:
1. vacuum manifold pressure too high
2. RFPA not correctly adjusted
3. mass filter contacts shorted or otherwise not working
4. mass filter not working correctly
5. MSD electronics not working correctly

What I've done;
1. checking the pressure through the software: in Diagnostics/edit ms params, forline pump is at ~14(mTorr?).
2. also in Diagnostics/set RFPA - attempted adjustment failed; clicking on set RFPA causes software to do I/O test. I dont know why. (I/O test passes)
3.-5. Only thing I can think of here, is to re place the entire quad assembly (the door)

Called Agilent, waiting for a callback.

If anyone has insight into this, I would be happy to hear any suggestions.

Thanks

[dr_bahram1977]

you said you can't get it turn on.
please let us know exactly which stage you stuck. and what you get on LCQ .
can you connect to software? what is prompt from chesmtation? can you tune? if no, what is result.
your vacuum is not low at all. under 100 is enough to start. check to see if your high vacuum pump turns on and gets warm or not.
I think your problem could be from electronic parts, especially ion lens.

[James_Ball]

Do you have the ion gauge for monitoring the High Vacuum analyzer pressure? If so that should be in the 10^-5 range before you are good to go. For the 5973 you need the stand alone gauge controller, unlike the 5975 those were not built into the software.

Leaks or high pressure in the vacuum chamber can cause that error, as can a bad side board. Also look at the analyzer and make sure none of the bare wires that surround the back end of the analyzer tube are grounding against something. I once hit one of those and because they will move easily it moved enough to ground against part of the analyzer and gave me that same error.

[thohry]

Why do you know the manifold pressure is too high ?
You can make a scan without turning on the calibrant and see if N2 or H2O is too much and then can conclude that the manifold is leaked.