ryan.crouch@LIGO.ORG - posted 11:16, Wednesday 30 August 2023 - last comment - 14:42, Thursday 07 September 2023(72558)
OPS Wednesday day shift midshift update
We've reaquired NLN at 17:52UTC after a lockloss this morning but we're not in observing due to a potential electronics issue on FC1 for the squeeze system which is being investigated.
It seems to be an issue with the T3 BOSEM on FC1
OSEM spectra of T3 BOSEM on FC1 shows that it is very noisy compared to the rest - see pic attached. Fil and I power cycled AA chassis and that did not make any difference. Fil and Dave are currently power cycling HAM7 electronics chain and Dave is also restarting the models (SUSH7).
I have moved all suspensions in HAM7 into SAFE state.
Power cycle of h1sush7 IO Chassis has not fixed the issue, front end computer has been powered off a second time, Fil is heading out to replace the first ADC.
BOSEM T3 is now looking healthy after Fil replaced ADC card, as shown in the spectra attached below. So we are back in action.
Ryan and I have brought all the suspensions in HAM7 to ALIGNED state.
Replacing the first ADC has resolved the FC1 T3 OSEM issue.
Work done under WP 11401.
FRS ticket 29047 filed and closed
https://services1.ligo-la.caltech.edu/FRS/show_bug.cgi?id=29047
Observation time lost due to this fault was approximately 6 hours.