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Reports until 15:57, Tuesday 18 August 2015
H1 SUS
betsy.weaver@LIGO.ORG - posted 15:57, Tuesday 18 August 2015 (20652)
More ESD fun

During troubleshooting of various stages of relock this afternoon, we noticed the ETMx ESD looked "funny" so Richard headed out to EX this time in search of a cure.  By "funny" we mean the 4 QUAD signals were the same sign as the DC - normally they are opposite.  As well, when Richard got to the end station, he found the HV ON/OFF switch was being toggled (audible at the rack) repeatedly so he unplugged the Binary cable which stopped it.  He toggled the HV ON/OFF a few times to see about clearing the sign issue.  Then, after a round of conversation, we found the BIO L3 HI/LO VOLTAGE and HI VOLT DISCONNECT were in the OFF positions on the ETMx - this is an incorrect state for acquisition.  So, I have written into the SAFE.snap to restore the ETMx to the HI Voltage state after a restart.  AFter all of the rack manipulations and a correct set of MEDM switches were thrown, the ETMx ESD seems healthy.  On with locking attempts.

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