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User name Kalyan
Log entry time 06:36:00 on January 25, 2009
Entry number 257726
This entry is a followup to: 257715
Followups:
keyword=Controlled access activity to fix the BB DAQ
There were two problems on the BB DAQ. First, there was high dead time
during a production run. Remote power cycling crates did not help so I
had to go to the hall to reset them manually. This could have solved the
problem(it did many times) but sometime while I was fixing this the
second problem occurred - something caused BigBite CAMAC crate fuse to
blow(which we obviously did not noticed, as we were busy fixing the first
problem). This caused all the thresholds on the wire chambers to go to
zero and that lead to crazy noise in the fastbus modules. This in turn
caused the automatic reboot of ROC 9 and 10 as soon as I run CODA.
Initially, after talking to Bob on phone we were thinking that fastbus
power supplies might have problems(as they were showing low read back on
5.2V and 2V..Jack fixed them later). Jin and I replaced the fuse on the
CAMAC crate. The fuse holder is broken so we had to put something to hold
it together.
Back to production ...