Problems of Tuning action stopped, GC/MS is just noise

I got the following error while tuning the MS 5975C. "Tuning action stopped: gain and offset = 0 and the peaks are too narrow." The void seems fine at 3 e-5.
This happened from one moment to another, the equipment was working normally and the tune stopped happening.
It has been made:
-Source cleaning according to Agilent recommendations.
-Change of filaments.
- PFTBA filling

None of this has worked and it continues to show only noise.
Annex images.

This is the last tune when the equipment was running:

These are the images when performing the autotune and the message that appears:

Any idea what else I can try?
thank you

  • ONE:   In Manual Tune, change the AMU offset to, oh, something like 100 (instead of 123) and the AMU Gain to 1600 (instead of 1858), Then with the PFTBA ON and the filament ON, do repeat profile scan of the tune ions and set the window to 10, or even 20 -- wider than normal.  In an operational system that should give you really wide and ugly peaks, but peaks.  It's changing the scan to be like the purple line below.

    TWO:   Try loading and running STUNE.U .  Maybe the tune file is corrupt.  That is rare but happens.

    THREE:   It's a diffusion pumped system. How long since the last preventive maintenance was done on the diffusion pump? How long since the last preventive maintenance was done on the rough pump?

    And then it's time to contact Agilent Service at your country's toll-free number - in the US it is 800-227-9770. That MSD was built in 2008!

  • Hello thank you very much.




    3.  The pump was recently checked

Reply Children
  • This has all been on Filament 2.... have you tried Filament 1 ?

    Can you feel the PFTBA valve click when you set to OFF/ON  in Manual Tune?

    If I was in front of it, I would vent, remove the ion source, take it apart again and make sure it was assembled properly, use a voltmeter to ohm out the filaments, and check the connections inside including the HED and the EM. I would verify the diffusion pump fluid level is in the proper range. Then pump it down and test again.

    After that the next step would be to contact the local toll-free number and start the process of getting onsite support.

  • Hello, with the support staff the voltages of the electronics were reviewed following an Agilent service note and it is found that the sideboard card cannot vary the voltage that allows the quadrupole to drive the ions to the high energy diode (which does not allow see the masses), indicating that the change of the sideboard is required... Can this be a definitive diagnosis?... HED and EM have not been reviewed... What is your recommendation?

  • Which voltage test point?    The sideboard is permanently damaged if the cables are connected to it while the power is on.  Did that happen?

    Notice in your picture above that the HED is set to On.

    If the HED power supply is not functioning properly and providing -10,000 V through the thick white wire to the connector at the back of the analyzer, then there will be no peaks. BUT, you may be able to see peaks if you increase the EM Volts. At the very least increasing the EM Volts should change the size of the background/noise peaks that are seen in your screen capture.   Try increasing the EM Volts, 2200...peaks? 2400...peaks?  2600...peaks?  If increasing the EM Volts gives peaks, then the best guess is that the HED power supply has failed, and not the side board.   If increasing the EM Volts increases the background/noise peaks, that tells you that the electron multiplier and signal processing circuits are working, at least.

  • Hi how are you, I was gathering information. We had another visit from a technician for a second opinion and this was his report:

    Diagnosis: The Mass Detector is not able to perform the AutoTune and the Manual Tune, it has no response only background noise, so it is believed that the Side Board is damaged, diagnostics were made which shows a problem of abnormal voltage drop when optimizing the frequency by moving the 2 coils of the Quadrupole of the Mass Detector,  additionally it was found that the supply voltage is somewhat high (120 – 121 VAC) and it is reported that there have been blackouts in said electrical supply…  I attach the tests performed. 

    According to these diagnoses I wanted to highlight some questions:

    1. Can it be said that the Side Board failed? ... The consultation is because it is an expensive piece and we want to be sure that it is what we should buy.
    2. We also receive indications that the MainBoard may be affected... if so... does the Main Board of an Agilent 5977A mass detector work for our 5975C mass detector?Reports 16 08

    Thank you.. 

  • 120-121 VAC is fine.

    The technician "dipped the quad" - that's the frequency optimization described, but doesn't say what the abnormal voltage drop is.  Can you get more information?

    This surely could be a side board, but I would want to check a few other things first if I was onsite.  The tests in that report were designed around the 5975 a long time ago. The 5977C uses different tests.

    No, the 5977A main board cannot be used in a 5977C.

  • Thanks for your quick response. 

    According to his answer... This surely could be a side board, but I would want to check a few other things first if I was onsite...   Since we do not have the possibility of your visit (although we would love to) ... What can we review on site to give you feedback and get closer to a definitive diagnosis? 

    Again thank you very much for your diligence and being so attentive and willing to collaborate with us.

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