Reports until 14:47, Saturday 13 April 2019
H1 ISC (ISC)
corey.gray@LIGO.ORG - posted 14:47, Saturday 13 April 2019 (48466)
ALS Polarization Changes This Morning

Just wanted to show a plot of what happened when I remotely adjusted the polarization.  The thing which surprises me every time is how the polarization values take a jump  (ALSy went from 35 up to 170%!) when I turned ON the AC power (or it could have been from hitting the RESTORE button). 

Luckily it was fairly easy to minimize ALSy though...able to get it to under 1%.  I powered off the system and then moved on.  However, DIAG_MAIN caught my eye and I noticed now ALS X had high polarization (around 25%).  So I quickly took H1 down & repeated the process again to minimize ALSx (I could only get down to 17% though.)  After this, returned to locking H1 with no issues.

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