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Reports until 14:42, Friday 20 December 2013
H1 SUS
jeffrey.kissel@LIGO.ORG - posted 14:42, Friday 20 December 2013 (9045)
Open Light Current Offsets and Normalization Gains Set for H1 SUS SR2
J. Kissel, J. Bartlett, A. Ramirez

We've measured the open light currents on the newly cabled up H1 SUS SR2 (with a metal dummy mass), calculated and applied the compensating offsets and normalization gains, captured a new safe.snap, and committed it to the userapps repository. Details below!

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Using the matlab script
/ligo/svncommon/SusSVN/sus/trunk/Common/MatlabTools/prettyOSEMgains.m
the captured open light currents and calculated normalization gains and compensating offsets are

>> prettyOSEMgains('H1','SR2')
OSEM  OLC [ct] Gain     Offset [ct]
M1T1   25985   1.155   -12992
M1T2   26833   1.118   -13417
M1T3   25702   1.167   -12851
M1LF   31475   0.953   -15738
M1RT   25346   1.184   -12673
M1SD   25571   1.173   -12786
M2UL   25576   1.173   -12788
M2LL   27473   1.092   -13736
M2UR   24401   1.229   -12201
M2LR   26282   1.141   -13141
M3UL   26043   1.152   -13021
M3LL   25772   1.164   -12886
M3UR   25342   1.184   -12671
M3LR   24901   1.205   -12451

These were manually installed in the H1:SUS-SR2_${ISOSTAGE}_OSEMINF_${DOF} bank, with ${ISOSTAGE} = [M1, M2, M3] and ${DOF} = [T1, T2, T3, LF, RT, SD] or [UL, LL, UR, LR] for M1 or M2/M3, respectively.

Though Mark has written a nice utility for capturing safe.snaps (see LHO aLOG 5202), we needed to get this done fast, I hadn't used it before, neither Mark or Arnaud are here to help us if it breaks, so we captured the files "by hand" (which is quickest for me), hence:

(1) Turned OFF the masterswitch.
(2) Turned OFF all requested DAC drive (LOCK, TEST, and OPTICALIGN outputs all OFF), other than the damping filter outputs which remain ON.
(3) Made sure the band-limiting filters were engaged in the filter banks preceding the watchdog trigger values.
(4) Captured each suspension's safe.snap, saving over what is in the userapps repository, e.g.
controls@opsws0:burtfiles 0$ pwd
/opt/rtcds/userapps/release/sus/h1/burtfiles
controls@opsws0:burtfiles 0$ burtrb -f /opt/rtcds/lho/h1/target/${ifo}sus${optic}/${ifo}sus${optic}epics/autoBurt.req > /opt/rtcds/userapps/release/sus/${ifo}/burtfiles/${ifo}sus${optic}_safe.snap 
(3) Ensured that the link to target directory (which is where the front end *actually* looks during reboot) was in place, e.g.
controls@opsws0:burt 0$ pwd
/opt/rtcds/lho/${ifo}/target/${ifo}sus${optic}/${ifo}sus${optic}epics/burt/
controls@opsws0:burt 0$ ls -l safe.snap 
lrwxrwxrwx 1 controls controls 63 2013-01-17 12:46 safe.snap -> /opt/rtcds/userapps/release/sus/${ifo}/burtfiles/${ifo}sus${optic}_safe.snap
(4) committed the new safe.snap to the userapps repository,
controls@opsws0:burtfiles 0$ pwd
/opt/rtcds/userapps/release/sus/h1/burtfiles
controls@opsws0:burtfiles 0$ svn commit -m "Installed and captured new open light current gains and offsets." ${ifo}sus${optic}_safe.snap
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