WP 12747
The negative rail power supply for ISC-R3 and ISC-R5 failed this morning. Fan seized and power supply tripped off. We opted to also replace the positive 18V since IFO was already down. When power was restored, we verified the fast shutter chassis HV was enabled. Control room reported issues with the PZT/shutter readback signals. On the floor we found the PZT driver chassis was powered off. Chassis was power on.
Rack ISC-C6 (U25-U27)
Power Supplies Removed: S1202017 and S1201944
Power Supplies Installed: S1201912 and S1201915
F. Clara, R. McCarthy, T. Sanchez
This Power Supply Failure did cause a lock loss.
we held in Check_AS Shutters due to this same power supply failure.
NLN reached by 17:21:50 UTC
Observing reached by 19:47:01 UTC