Jason noticed that the chiller was complaining about low water level as he was bringing it back up. This is apparently due to the fact that when the chiller trips off, it burps a bunch of water onto the floor. I topped the Xtal chiller off with 300 mL H2O.
travis.sadecki@LIGO.ORG - 22:56, Monday 05 December 2016 (32224)
Sorting through the myriad of signals leads me to think that the laser trip was due to the NPRO passing out.
Although it is possible that the flow rate in head 3 dipped below the 0.4 lpm limit. Head3FlowNPRO.png
suggests that the NPRO tripped out before the flow rate in head 3 reached its limit.
Images attached to this comment
jason.oberling@LIGO.ORG - 09:28, Tuesday 06 December 2016 (32239)PSL
When restarting the laser last night, the status screen on the PSL Beckhoff PC indicated a trip of the "Head 1-4 Flow" interlock; although looking at the graphs Peter posted above it appears that the laser lost power before any of the flow sensors dropped below the trip threshold.
jason.oberling@LIGO.ORG - 10:30, Tuesday 06 December 2016 (32243)
Further forensics: Attached are trends of the laser head temperatures around the time of last night's PSL trip. To my eye nothing looks out of the ordinary.
Jason noticed that the chiller was complaining about low water level as he was bringing it back up. This is apparently due to the fact that when the chiller trips off, it burps a bunch of water onto the floor. I topped the Xtal chiller off with 300 mL H2O.
Filed FRS ticket 6853 for this trip.
Also, back to Locking now.
Also, Rana and photographer are on site. I let them onto the Observation Deck to take pics while we are relocking.
When restarting the laser last night, the status screen on the PSL Beckhoff PC indicated a trip of the "Head 1-4 Flow" interlock; although looking at the graphs Peter posted above it appears that the laser lost power before any of the flow sensors dropped below the trip threshold.
Further forensics: Attached are trends of the laser head temperatures around the time of last night's PSL trip. To my eye nothing looks out of the ordinary.