Our system was shut down for few months. Now I am trying to tune the MS. I am new to Polaris Q.
I started with Tune option and all controls-passed. Vacuum is under the required range.
But, I dont see ant peaks after air/water check. Besides, mass spec will not tune. After autotune, it says tune failed or was stopped by user. Tune file does not show any peaks and says mass calibration was not run. In fact, i do not find any peaks on the window!
Any solution?
Some generic help, not specific to this system: check to make sure your calibrant vial has calibrant (such as PFTBA) in it. Other possibilities are detector failure or filament burnout.
For my experience for autotune, it is normally fail when:-
1. Your system get a lot of moisture especially when you switch off in the long time. I always practice to leave more than 1/2 hour before tuning the system.
2. In some cases, you will also check the vacuum pump speed. It is the pump is running completely 100 % and the temperature same with your setting temperature. If this not function properly, it will cause your system MS was not in vacuum condition and the moisture will still in the system.
3. Burn filament. If your sample use a lot of solvent to analyse (not use solvent delay) or use the very concentration sample; your lifetime of your filament will be shorter and maybe easy to burn out.
4. If you have experience use manual tune, you can try to use it before autotune. Normally, if your manual tune give the bad result; it will cause the faller in Autotune.
Thank you.
Best Regards,
Fauzi
@ Parsons and Ahmad, thank you so much for your answer.
Can you please let me know how to diagnose the filament failure?
@Ahmad could ypu please tell me what are the values to be put in manual tune?
generally filament failure will cause you to have no peaks on detector (just noise). You will need to manually inspect the filament to be sure. Most instruments have two filaments, so you can try switching the one that's being used in the software, possibly.
Also a general guess: if there is any other possibility to start with, then start. E.g. Cal gas tuning, RF ramp calibration and similar. In Varian MS, you do these first two, then only you'd see the Air/Water Check results. Continue with eventual Bakeout, then Autotune.
Seeing nothing, I think the first question should be - is the filament working? This is easy to check. Remove the top panel of the Polaris Q you will be able to see through the glass top whether the filament is working or not. It is located on the top of the source and there should be a incandescent glow if it is working.
The next think to check would be the electrical connections to the source itself. Following a source clean and re-positioning of the source on its lugs, the electrical connection assembly needs to be connected. It is possible this has not been pushed firmly into place. It may look OK from outside but this is not a reliable guide. You will need to vent and manually check the connection.
Hi Brendon A Parsons, Sándor Forczek and Charles H Hocart thank you for your valuable suggestions.
@ Hocart, yes, as you said now I am opening the MS covers and let me inspect. I will get back to you soon. Thank you so much.
I think you should clean the font, check the font connections if you haven't done that in months. Or do deeper tests, it could be some board that burned, or a temporary bug. Or try leaving it for 12 h with vacuum and decreasing humidity, and then do a diagnosis, before everything else in the tune.
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