Hi penny,

I had this recently due to a power failure. On the 55V power suply the +15V
(or -15 I don't remember) one of three leds was off. Pulling loose the cable
to the amplifier board and connecting it again helped.

regards,
Arnold

Penny Higgins wrote:

> Arrrgh!
>
> I am trying to run some H2 standard on-offs with our Delta plus XP (I'm
> running water dD with the Gas Bench). Alas, I seem to have cup 5 (mass 3)
> maxed out at 50 mV and I can't seem to un-max it. I've tried shutting off
> the source, restarting the computer, starting a sequence, peak centering,
> and jumping to different masses. It's just stuck at 50 mV. I didn't just
> lose my cup, did I?
>
> Does anyone have a quick and painless solution to this wee problem?
>
> Thanks,
>
> ~Penny
>
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>                        Dr. Pennilyn Higgins
>                         Research Associate
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>    Stable Isotope Ratios in the Environment Analytical Laboratory
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