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Reports until 16:15, Monday 16 June 2014
H1 AOS
hugh.radkins@LIGO.ORG - posted 16:15, Monday 16 June 2014 (12380)
WHAM5 ISI Generic Isolation Loop (Lvl1) only works with 100mHz Blend

Started with the 750mHz.  It would trip the Actuator with the script so went to hand method.  Going dof at a time, was able to get the RZ RX  & RY dofs on with boosts and they were pretty quiet.  Could get Z on too but it would go unstable quickly when either the X & Y dof was included.  Checked the local to cartesian matrices and they are correct.  Looked at the parameter file in case the loops were created with incorrect matrices...but I could not find that info in the parameter file so not sure if you can determine that.  I did then spot the Blend filter and it said 01_28.  So, I changed the blend to 01_28 and tried the script again but it would still trip out quickly.  Same story on the 250mHz.  However, it is stable with the 100mHz blend...weird.

Attached is a isolated/damped only comparison.  The reference traces are with the lvl1 isolation and 100mHz blends.  The current rraces only have damping engaged.  This isolation does a fair amount of good in various places especially below a few htz but it appears to have resonances and other ill effects at various places above several htz....

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