Agilent 5975 MSD - No filaments lighting

Discussions about GC-MS, LC-MS, LC-FTIR, and other "coupled" analytical techniques.

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I have an Agilent GC/MSD 5975. Currently (no pun intended) neither filament will light even though both are good (tested) and the mass spec will "turn on" with multiplier voltage and everything else with no messages being generated.

I tested both of the filament contact points on the external board on the sideboard, with each one turned on, respectively, and there was no current (uA) to either in both cases. No other problems are evident so I suspect the controller to the filaments OR some power supply. I would rather not have to bring Agilent in if I can easily diagnose which board needs to be replaced, ie is it the power supply board, sideboard, main board,etc. etc. Unfortunately, I don't have any schematics to let me know which test points to use on any of the boards.

Does anyone have any schematics or advice?
One historical aspect that may be indicative of what is going on - couple of months ago, I had a similar problem when Fil 1 would only light at a very very dim intensity while Fil 2 would not light at all. Both filaments tested fine. Restarting the entire system didn't help. The way I solved it last time - not on purpose - was to have the whole thing off for about an hour and then turn it back on. It worked once again so I thought that there was some type of communication problem with it. Now, though, that doesn't seem to be an appropriate solution, and I am suspecting power supply problems although I am surprised that there are no error messages.

Thanks,
Nick

This might be a silly question but is the EM ok? I had a problem with the filaments as well, turned out though the filaments were ok and when I replaced the EM the instrument was fine. You are not getting any fault numbers show up?

A silly answer. How tight are the connections from the MS to the filaments? If you vent and open the source you should not be able to pull the wires from the filaments with a gentle tug ( using forceps). If they are loose you can GENTLY crimp the conections with pliers. Use care as there is no turning back ( if they are over crimped the wires will need replacement).
Did you ever figure out what was causing this? I'm experiencing the exact same problem at the moment. Did a source cleaning and filament replacement, tried to do a tune right after it pumped down - the filament lit fine but the ion peaks looked terrible, unlike I had ever seen them before. Figured I needed to let it equilibrate a bit longer, came back couple hours later, tried again, filament lit and peaks are terrible again. Then I try another tune on the original filament and also switched to the older filament, and it's doing this thing where I hear the click, no problem is detected, but neither filament is lighting. Re-vented, checked all the wires, pumped down again, still nothing.
Try and run a different tune. Like s tune or bfb tune. Every so often the tune file can get corrupted. If your a tune is corrupt there are "spares" under the set up files. I can't remember how to replace the file at the moment. Call the 800 number and Agilent will walk you through it.
thanks problem solved! pretty sure you were right about the corrupted tune file, since the only other thing i changed was trying to crimp the wire connectors a bit tighter (doubt that was responsible).
Just now I ran three samples and everything is fine. How ever, for the last sample I changed source temperature to 300 C (from 230). Then went back to source temperature 230C. MSD source capable of running at 350C (Agilent 6890N/5975C).

Now, the filaments are not lighting up and no signal.
I tested with different tune file. Power cycled MSD and computer.

Still no luck. Any thoughts.

Thank you,

Dhan
Hi
Are you getting the filament current error ( cannot remember the exact name ) or no signal error?
The higher temp may have opened the filaments.
I am using High Temperature filament G3170-60050.

No. I did not get any error message. I think, Agilent implimented safety feature to disable filament power when using source temperature at or above 300C. I am using latest build E version.

I tested both the filaments and they are good.

No voltage going to filaments (tested with multimeter). Other functions are fine on the side board (heating source and quad)

Thank you,

Dhan
I am having the same problem with our 5973 MSD.
I get the "no emission current" error 8.
I have replaced both of the filaments with the new white 4-coil ones and its still erratic.
Sometimes it will stop part way through a tune, sometimes part-way through a sample, often the filaments won't come on at all. Its basicaly unusable.
The 4 connections to the filaments felt fine after I did a recent source clean.
The vacuum is really good, virtually no air or water, I just can't work out what the problem is. I'm worried its the sideboard or topboard, which I have no clue how to fix.
Our EM is getting a little old/high, but I would expect to get a different error message if that was the problem.
Hi

Was the error erratic with the older filaments or did they just fail and never work again?
In general filaments should just fail. Firstly clean the source and while you are at it check the filaments are not open circuit. Also check filament cable connections to the source and the ribbon card that runs from the side board to the main board, make sure it is not broken.
Get back to us if that doesn't work.
I checked all the filaments, old and new, with a multi-meter and they were all fine.
Then I started having problems with the software not updating to the 'correct' filament when I selected it.

We now have a new GCMS and I have put the source from our problem one into it and it works beautifully.

So I think it is probably the sideboard or topboard on the old one.
If you do not get a 'no emission current' error and you hear the cal gas valve click when you go to manual tune and try a scan or profile, then the most likely issue is the foreline pump. Agilent has insisted on sticking with the complete garbage Pfeiffer foreline pumps, as everyone must know already. My suggestion: install an old Edwards E2M2. What is interesting is the vacuum will say it is OK, the turbo will come to full speed, but somewhere the logic will not allow the filaments to turn on.
It was an Edwards pump that we had on it. It turned out to be a flaky mainboard, which was not surprising given its age. That is why Agilent were offering mainboard upgrade packages, which the Uni chose not to fund the year before.
I also had a ton of trouble with the pfiefer foreline pumps. I use Edwards E2M1.5's which used to be speced with the 5973's. Anything stronger probably shouldn't be plugged into the MSD.
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