HW-Time-Slice Firmware-Filter Software vx2740 Steering Module Reports MVM MVM Vexos MVM-Bug listing MVM TRIUMF Local DS Prototype DS Cryogenic For Shifters BCIT-31 ChronoBox Run Operation DS-DAQ
  CERN DS-Proto0 read-only backup  Not logged in ELOG logo
Message ID: 13     Entry time: 11 Nov 2019 04:08
Author: Yi Wang 
Type: Problem 
Category: Cooling System 
Subject: Possible power blackout on Nov 9 

There was a possible power blackout on Nov 9 from 2 am to 4 am at builidng 182.

During the blackout, the vacuum pump for pumping the insulation vacuum of the cryogenic system was OFF.

Moistures were accumulated in the interlayer during these two hours, and now the vacuum insulation is not as good as before.

This causes some bubbles generating in the liquid delivery bellow and significantly reduces the fast recirculation speed.

ELOG V3.1.4-cb3afcd8