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User name miham
Log entry time 02:27:19 on May28,2009
Entry number 276978
keyword=Hall-A ALARM - Compton HV tripA 1:50am the HallA alarm started beeping saying that there is a
problem with LeCroy HV (MF2alarm). We checked the HV gui for
the left arm and Beam line. In the left arm everything was green.
For the beamline the title was red but all the channels were green.
We didn't know where the problem was. I have called Alexandre and
he told me to check a Compton HV in more detail. The problem was indeed there : channel 1 in slot 11 tripped. We turned the HV back on
and the alarm went away. (Why was the number in the gui green if the channel tripped.)
We have tried to figure out what caused the trip and when we checked
the beam strip charts we saw that at that point beam position
changed dramaticaly. We believe that this was the reason.
FIGURE 1
FIGURE 2
