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!