Chromatography Forum

My 5971 is having problems turning on. When I depress the on/off toggle switch to turn the MSD on the switch automatically reverts to the 'off' position and I here a winding-down noise - all happens within a second. I thought at first the rough pump was drawing too much power so I unplugged the rough pump and still the same thing happens.

This problem has been occurring more and more over the last year. I've had to turn off the MSD probably about 10 times over the last year due to building construction issues, Smart Card replacement, electron multiplier replacement, etc. I've noticed this problem more and more frequently. For instance a year ago, the MSD may have actually turned on after the 2nd or 3rd attempt. However lately it's more like 5-7 attempts to actually get it to turn on.

I would appreciate any insight into this problem. Any ideas? power board, the switch itself?
Many Thanks,
Jean

Is your MSD on it's own circuit? If you have a 120 volt MSD, it needs a dedicated 15 amp circuit that provides 120VAC +5%/-10%. I'd check the power from the outlet first. Is the circuit on a UPS? If so, it needs to be a 900V/A UPS. Please let us know what you find.

From the way it is switching off, sounds as if that switch is also a breaker. Either there is too much load being pulled through the switch or the breaker part is getting weak. May need to change out the switch if you can find one.

James_Ball - you are the winner!! I replaced the switch and it turns on just fine now!!

P.S. -- Got the switch super fast from wntechnical.com! ...and some great over-the-phone diagnosing as well. THANKS!

I'm glad it was the simple fix