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Entry  Tue Oct 28 01:12:57 2014, Jenne, Update, SUS, ETMX bad :( 
    Reply  Tue Oct 28 02:44:08 2014, Jenne, Update, SUS, ETMX bad :( 
       Reply  Tue Oct 28 11:45:21 2014, manasa, Update, SUS, ETMX - observation 
Message ID: 10645     Entry time: Tue Oct 28 11:45:21 2014     In reply to: 10644
Author: manasa 
Type: Update 
Category: SUS 
Subject: ETMX - observation 

I looked at what are the situations that make ETMX lose alignment.

This is not occur all that often this morning; less than 10 times in may be the last 4 hours of poking the X arm. I found that the bad behavior of ETMX also exists in certain other cases apart from the case when we enable LSC.

(I) Even the MISALIGN and RESTORE scripts for the suspensions make the suspension behave bad. The RESTORE script while in the process of  bringing back the suspension to the place where it was, kicks it to some place else sometimes (even with LSC disabled)

(II) The suspension also gets kicked while realigning ETMX manually using sliders at 10^-3 (pace of 2-3 steps at a time).

I am suspecting something wrong right at the coil inputs and gains of the suspension.

Also, I recollect that  we haven't done a check on the X arm LSC limiters and filters ramping times like it was done for the Y arm ( Elog 9877 ). We should do this check to be sure that we are not seeing a mixed puddle of problems from 2 sources.

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