Reports until 18:20, Monday 09 May 2016
H1 ISC
sheila.dwyer@LIGO.ORG - posted 18:20, Monday 09 May 2016 - last comment - 13:56, Tuesday 10 May 2016(27082)
another brief look at XARM IR

Sheila, Jenne, Cheryl

Xarm IR locking was difficult again today, and we made two observations. 

We have a more aggresive low pass filter in MC2 M3 than we really need, CLP300.  We locked the arm twice sucsesfully with this filter off and CLP500 on instead. screenshots are attached with the digital gain set to 0.15.  We didn't add this to the guardian yet, but I think its a good idea (third screenshot attached shows the trial configuration).

We are in no danger of saturating M3, but M2 saturates when we are trying to acquire.  This might be the root of some of our troubles accquiring the xarm.   

Images attached to this report
Comments related to this report
sheila.dwyer@LIGO.ORG - 13:56, Tuesday 10 May 2016 (27093)

I've tested this new arrangement about 10 times in the last 15 minutes, and it does seem much better than what we had before, so I've put it in the guardian and committed them.