Reports until 15:20, Tuesday 14 July 2015
H1 SEI
hugh.radkins@LIGO.ORG - posted 15:20, Tuesday 14 July 2015 - last comment - 08:56, Wednesday 15 July 2015(19632)
LHO SEI HEPI Fluid System Accumulator Charge Check

All fifty (50) Accumulators were checked for charge today.  No Accumulator needed charging.  Only three accumulators showed a decrease in pressure since the last charge check on 21 April, see T1500280.  These were small decreases (few psi) and likely reflect loss from gauge pulloff (does the uncertainy principle apply?)  The acceptable range of 60-93% of operating pressure is quite broad and the lowest reading today was at 80%.

Given these results, and, the reservoir-fluid-level-indication of Accumulator charge which can be checked with the system pumping, this invasive, must have system off accumulator pressure check could be done just quarterly.  As long as the weekly check of reservoir fluid levels show no decrease, the accumulators can be assumed to be adaquately charged.  If a weekly check of the reservoir fluid indicates a volume loss, then the accumulators could be checked.

Comments related to this report
brian.lantz@LIGO.ORG - 08:56, Wednesday 15 July 2015 (19665)
good to hear that the accumulators are holding well. I like your plan
-Brian