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H1 General (OpsInfo)

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cheryl.vorvick@LIGO.ORG - posted 11:23, Friday 14 October 2016 - last comment - 16:40, Friday 14 October 2016(30535)

Ops Morning Update: as of 18:18UTC, Winds have picked up, locking is questionalble

State of H1: in Initial Alignment, struggling to lock arms in green, have only had breif locks of X arm in IR

Details:

winds between 10mph and 45mph across the site
BRS at EX and EY turned off
X arm in green locked but dipping below 0.5
IMC on relock is pushing on MC2 so much that it's wise to pause in Ready to let it settle
NPRO Noise Eater had to be reset twice, this seems like a apttern, like possibly the first reset doesn't really restore the system to a nominal state, and another reset is necessary
useism is high, attampt to change BRS to WINDY_USEISM but didn't work as expected, set X by hand, Y is rung up so not being used
- small guardian code issue resolved by TJ, guardian behavior resolved

Site Activities:

16:15-16:45UTC - Chandra to both EX and EY VEAs to colect serial numbers
16:40UTC - Bubba to EY to add glycol to equipment in the mechanical room
16:45UTC - EvanG injected into Pcal
17:15UTC - I reset the NPRO Noise Eater
17:29UTC - I reset the NPRO Noise Eater
17:52UTC - Bubba back from EY

Comments related to this report

krishna.venkateswara@LIGO.ORG - 12:04, Friday 14 October 2016 (30537)

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Both BRS seem to be working fine to me, I don't see anything wrong with BRS-Y.

cheryl.vorvick@LIGO.ORG - 13:02, Friday 14 October 2016 (30538)

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AS of 19:58UTC (12:58PT):

winds have come down from 15-45mph to a steady 0- 35mph, with gusts to 40mph
EY BRS is not in use, but damping, however the velocity is +/-1500 counts(?)
BRS set to WINDY_NOBRSY
cannot get through FIND_IR

cheryl.vorvick@LIGO.ORG - 13:03, Friday 14 October 2016 (30539)

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BRSY is rung up - see attached

Images attached to this comment

krishna.venkateswara@LIGO.ORG - 13:35, Friday 14 October 2016 (30541)

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Sorry, the terminology related to BRS is a little confusing, even to me. The large velocity signal is actually caused by the large ground motion and is not a fault of the sensor. The damping will turn ON occasionally but the sensor output should still be useable. I would suggest using the BRS under these conditions.

If you want to prevent the damping from turning ON in these very high winds, the ON/OFF VELOCITY can be set higher temporarily. I think the commands are -

CAPUT H1:ISI-GND_BRS_ETMY_HIGHTHRESHOLD 5000

CAPUT H1:ISI-GND_BRS_ETMY_LOWTHRESHOLD 2000

hugh.radkins@LIGO.ORG - 16:40, Friday 14 October 2016 (30546)

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Or you can disable the damping with:

caput H1:ISI-GND_BRS_ETMY_USER Off
Old : H1:ISI-GND_BRS_ETMY_USER On
New : H1:ISI-GND_BRS_ETMY_USER Off