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Reports until 16:43, Thursday 18 January 2018
H1 SUS
jeffrey.kissel@LIGO.ORG - posted 16:43, Thursday 18 January 2018 - last comment - 09:28, Friday 19 January 2018(40177)
H1SUSSRM RT SD OSEM Sensors were Dead -- Now Fixed
J. Kissel, R. McCarthy, M. Pirello

While trying to finally get around to finishing out the MEDM infrastructure for the new SQZ suspensions and the re-arranged OMs, we discovered that the RT and SD OSEMs are dead on SRM. They apparently died on Jan 10 ~19:30 UTC (about 11:30a PT). Remember, we know the problem is highly likely out of vacuum, since I was able to take successful transfer functions on Jan 3rd (LHO aLOG 40002). Much more likely -- Gerardo's Vacuum work mentioned in LHO aLOG 40090, or Fil and Liz's cable pulling mentioned in LHO aLOG 40085)

After tracing and confirming integrity and correctness of all HAM5/6 SUS cables from the AA chassis to the remote satellite amplifier, I noticed that two of the SRM (T3 LF RT SD) sat amp fault lights were on (see attached picture). Power cycling the respective SRM T3LFRTSD coil driver chassis didn't find the problem.  Talking with Richard, he suggested it was the last cable run from the sat amp to the chamber, since it's a tight squeeze getting the cable to seat properly at the feed through.

As suspected, he went out to diagnose and was able to wiggle the connection at the feed through enough to intermittently restore life to RT and SD, but didn't have the right tools to really make the connection secure, so he (or Fil) will finish out the fix tomorrow morning.
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Comments related to this report
richard.mccarthy@LIGO.ORG - 06:29, Friday 19 January 2018 (40191)

This morning I was able to remove the strain relief cover and get to the connector. The aligo feedthrough are more finicky than iligo so clear access is needed to insure the 25 pin cables are seated properly.  All OSEM signal are present on the MEDM

jeffrey.kissel@LIGO.ORG - 09:16, Friday 19 January 2018 (40195)CDS
J. Kissel, R. McCarthy

Ran a (damping loops closed) set of top mass transfer functions for a health check after Richard has properly seated the cable. Functionality appears to be completely restored. Nice work!

I haven't exported and properly processed the data yet, but the data files are committed to the SVN here:
    /ligo/svncommon/SusSVN/sus/trunk/HSTS/H1/SRM/SAGM1/Data/
        2018-01-19_1618_H1SUSSRM_M1_WhiteNoise_L_0p01to50Hz.xml
        2018-01-19_1618_H1SUSSRM_M1_WhiteNoise_P_0p01to50Hz.xml
        2018-01-19_1618_H1SUSSRM_M1_WhiteNoise_R_0p01to50Hz.xml
        2018-01-19_1618_H1SUSSRM_M1_WhiteNoise_T_0p01to50Hz.xml
        2018-01-19_1618_H1SUSSRM_M1_WhiteNoise_V_0p01to50Hz.xml
        2018-01-19_1618_H1SUSSRM_M1_WhiteNoise_Y_0p01to50Hz.xml
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jeffrey.kissel@LIGO.ORG - 09:28, Friday 19 January 2018 (40196)CDS
Corresponds to FRS Ticket 9744.
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