PSL trip took down the IFO, or vice versa. No commissioners are on site currently, so I'm calling it a night (with Corey's approval). Stefan and other commissioners made noise about coming back in so they try to recover, but I don't have the procedure to restart the PSL.
TITLE: 09/29 Day Shift: 23:00-7:00 UTC
STATE of H1: PSL down
SHIFT SUMMARY: Lock was generally going well until the PSL went down, PI's were a learning experience, vigilance is required.
LOG:
23:00 IFO almost locked at end of Corey's shift
1:15 DRMI flashes non-existent, did initial alignment through MICH_DARK
2:00 NLN, PI Mode 26 immediately started ringing up, but tweaking phase brought it back down.
3:30 4 PIs ring up, 17, 25, 27 & 2, breaking lock before I could make any improvemts on any of them, but 17 rang up first
3:50 NLN, PI 17 rang up around power up, but managed to bring it down again
4:47 Lockloss, PSL is down
I have restarted the PSL. Looking at the status screen of the PSL, I have determined that the situation was exactly the same as those from yesterday (30063). However, because it was already late in the night, I decided not to call the experts. Instead, I by myself did the same recovery procedure as I did yesterday. I added 200 ml water to the chiller.
Thanks for handling PI's Jim. You saved a few locks.
Got in right as Jim was leaving. Looking back at the spectrum, it was only MODE17 that rang up during the 3:30 time; all other modes just had increasing RMS due to bleed over from the extremely heightened mode (note MODE27 did not ring up, it was MODE10 - I've changed the color to make this more distinguishable). This one had not been problematic since I implemented stepping filters and a smarter guardian to handle (several days now).
At 3:50 power up, MODE17 was still significanly rang up (since Jim relocked so quickly), hence seeing it right away. If lock is lost due to PI and you immediately relock, pause at DC_READOUT before power up to ensure mode is damped first. I'll go through this with operators.