Reports until 16:43, Monday 16 February 2015
H1 ISC
sheila.dwyer@LIGO.ORG - posted 16:43, Monday 16 February 2015 (16745)
End X input alignment servo off

Peter, Sheila

This morning we found that the input alignment PZT on ISCEZ had the output held, this apparently happened Wednesday morning around 10 am.  The attached trend shows the QPD inputs to the servos and the RMS of the PZT drive signal over the last couple of months.  The rms of the PZT drives is checked to see if the QPD servos are locked, the high threshold had been set to 150 previously but based on this trend I lowered the high threshold to 20.  At this level I think an error message would have been generated on Wednesday.  This probably contributed to our alignment problems over the last few days, when the QPDs were mis-centered more than earlier in the week. 

We were attempting to try locking after this, but have been slowed down by a large earth quake near japan.  

Images attached to this report