6110 Single Quad LC/MS Forepump does not start work issue

Hello everyone! 


   We have a 6110 Quadrupole LC/MS and it was doing fine until it misteriously turned off the fore pump (at morning we looked at the instrument and the MSD-self was worked although the fore and turbo pump did not at work). The same accident are repeated several times and after last one the MSD does not provide the power to the forepump.
   The forepump itself is good working from wall outlets and shows good-enough vacuum. The AC PFA (and all other PCBs) look like good and does not show any crashed or burned out elements. All the fuses (at the rear side, and at the two others power supplies inside the power aluminum box) are not blown.

   Turning on the MSD induces all the MSD fans blown, and after approx. 1minute some of the AC PFA LEDs are turned on, however the forepump socket on MSD shows zero voltage and forepump does not start work, although at the same time AC PFA provide 220V to the turbopump power supply. The ChemStation Log displayed the message "Foreline pressure too high to turn on turbo pumps." even if the forepump powered from the wall outlet and generate vacuum (i.e no matter forepump is in On or Off state - the foregauge is not On, and main idea is both the forepump and foregauge parts of AC PFA does not start work simultaneously possibly even from the same relay, although the both cables from forepump and foregauge first enter to AC PFA sockets)
   Does anyone have any siggestions about? I'm assuming the AC PFA power board where the power first enters the MSD but I want to exhaust other options first before commiting to such a ordering venture. 


Thanks in advance!

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  • Yes, rough pump - is Edwards E1M18. I checked one more time exactly all fuses of the MSD are good!

    Oil mist filter and exhaust hose are good enough and the rough pump does not start work and no any difference between the pump equipped with mist filter assy or the pump without mist filter assy.

    Moreover, I did disconnect the rough pump from MSD in order to measure the voltage in MSD socket for rough pump by multimeter (expecting to look 220V) and after I turned on MSD the MSD is really turned on and the multimeter displays totally zero volts (at the same time I did measure by second multimeter the 220V voltage in power cable for the Turbopump power supply) and after a little time the Chemstation get successfully connected with MSD where there is only one error message observed in Log “Foreline pressure too high to turn on turbo pumps.”.

  • Thank you so much for your answer! 

    Unfortunately the rough pump even does not try to start - no any noise or clicking or buzzing sounds heared from rough pump motor. The rough pump itself easily starts and good working from wall outlet. Afer start MSD I can firstly hear the quiet clicking sounds from relays on AC board only and after that fans blowing noise and nothing more.  


    What can i check yet? I mean according to system logic the rough pump and fore gauge should be start simultaneously with MSD start without any delays from other PCBs, for example, other internal power supplies, CPU board, or PCBs powering ion optics etc 

  • Good job on measuring the voltage!  If there is no voltage coming out of the MSD to the rough pump and the fuses are good, you most likely need a new AC board.  Without looking at your instrument in person please understand that this is no guarantee,  but based on your troubleshooting it sounds like the AC board is bad.


    P.S  A seized Edwards pump will generally try to start when the instrument is powered on:  you'll be able to hear a humming sound as the motor tries to start, but it will eventually turn off or a fuse will blow.

  • I think you have done as much as you can without replacing parts.  I would suggest at this point that you request service for Agilent.

  • Ok! Thank you so much for a help! 

    when some news about the issue will be available I provide the information

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