User name S. Sirca
Log entry time 10:30:34 on October28,2001
Entry number 75303
keyword=Cryo problems due to communication failures solved
The network problems affecting the ROCs earlier this morning
seemed to influence also the IOCs, in particular the iocha26 which
appears to be the IOC which controls the cryogen levels for the
spectrometers. This in turn caused the slow controls to fail to
control the flow of helium. In consequence, the magnets
(Left D1 and Right Q3) tripped for lack of helium. Although the
control screens in the counting room showed sufficient cryogen
levels, they did not update. The magnet power supplies were then
reset in the hall and the IOC 26 was rebooted, and we could recover
the magnets. But we could not restore communication to iocha26,
although we pushed both E_COM_RST and H_COM_RST.
The screen with the IOC heartbeats shows an empty slot for
iocha26 although MCC tells us it is alive.
We are now restoring magnet currents to their required values
for physics production.