Reports until 08:51, Wednesday 12 September 2012
H2 SUS
keita.kawabe@LIGO.ORG - posted 08:51, Wednesday 12 September 2012 - last comment - 14:13, Wednesday 12 September 2012(4167)
SUS channel names were changed, we cannot trend the old alignment offsets

H2:SUS-ETMY_M0_OFFSET_P etc. were changed to H2:SUS-ETMY_M0_OFFSET_P_OFFSET etc. yesterday, apparently, and ISC screen for TM offsets are now white.

More importantly, because of this, we can't trend the old alignment offsets from the past using data viewer. Thank you.

From OFFSET_P to OFFSET_P_OFFSET, and OFFSET_Y to OFFSET_Y_OFFSET. Sounds as if somebody decided that we needed to put a standard cds filter module just for the offset. I don't know why, but I can believe that there's some reason. Anyway , please talk to integration testers before making such a change next time.

Comments related to this report
jeffrey.garcia@LIGO.ORG - 09:47, Wednesday 12 September 2012 (4168)
Link 

This change was necessary in order to allow the ramping of the gain for the very large DC offsets.  Otherwise, instantaneously engaging these offsets trips the watchdogs.
jeffrey.garcia@LIGO.ORG - 10:22, Wednesday 12 September 2012 (4170)
Link 

The latest offsets for ITMY, ETMY, and TMSY are listed below:

H2:SUS-ITMY_M0_OFFSET_P 1 5.773156262190410e+03
H2:SUS-ITMY_M0_OFFSET_Y 1 7.655051822649471e+02

H2:SUS-ETMY_M0_OFFSET_P 1 -3.026901455243990e+03
H2:SUS-ETMY_M0_OFFSET_Y 1 5.405575230252840e+03

H2:SUS-TMSY_M1_OFFSET_P 1 -7.363600000000000e+04
H2:SUS-TMSY_M1_OFFSET_Y 1 1.919600000000000e+04

These values were taken from an hourly ".snap" file taken from the directory '/ligo/cds/lho/h2/burt/2012/09/11/09:00/'.
keita.kawabe@LIGO.ORG - 14:13, Wednesday 12 September 2012 (4171)
Link

Snapshots are not trends. Now we need to use NDS2 client for trending data from the past, which is OK but not ideal.