Reports until 03:23, Friday 17 June 2016
H1 ISC
stefan.ballmer@LIGO.ORG - posted 03:23, Friday 17 June 2016 - last comment - 11:11, Friday 17 June 2016(27799)
ASC engaging non-functional

Evan, Stefan

We didn't get past the ASC engaging tonight.

The one thing that clearly improved stability was setting the MC2 cross-over up by 4dB - before that even the slightest disturbances kicked the x-over into an oscillation.

After that fix, we at least didn't have any more immediate losses. 

 

However, the current ASC engaging logic doesn't work. It also doesn't seem to make much sense. We have convergence checkers, but they are currently used before all loops are closed. Thus we wait for one loop to drag us off into some direction, only for the next loop to come on and load up the previous loop again.

 

 

Comments related to this report
daniel.sigg@LIGO.ORG - 11:11, Friday 17 June 2016 (27808)

What changed? The MC crossover only depends on the actuator strength ratio between MFC and MCL.