aLIGO LHO Logbook

H1 SUS (CDS, SUS)

sheila.dwyer@LIGO.ORG - posted 23:04, Tuesday 26 May 2015 - last comment - 10:36, Wednesday 27 May 2015(18640)

ITMX PUM AI chassis not working

Evan, Kiwamu, Sheila, Jeff

We noticed that we weren't really driving ITMX PUM. Evan and I went to the racks and saw that the DAC outputs were changing, but the LED that says DAC WD next to the DAC input was not lit and there was nothing coming out of the AI board. This is probably why Dan was unable to damp ITMX violin modes last night.

Comments related to this report

sheila.dwyer@LIGO.ORG - 23:46, Tuesday 26 May 2015 (18641)

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h1susb123 has stopped running, the symptoms are verry similar to what happened yesterday. There are several red block on the CDS overview screen, front end models are not synced to the IOP.

This coincided with kiwamu pulling out the AI chassis for ITMX L2, although we aren't sure if this is related or not. We don't know how to restart this without causing a problem for the dolphin network, so we're done locking for tonight.

daniel.hoak@LIGO.ORG - 00:41, Wednesday 27 May 2015 (18645)

Link

AH-HA!

filiberto.clara@LIGO.ORG - 10:36, Wednesday 27 May 2015 (18649)

Link

Replaced the 18-bit DAC Anti-Image interface board (possible bad optocoupler) for AI Chassis S1103818.
 
Board removed S1103833
Board installed S1105351

Chassis was reinstalled and powered up. Verified both DAC WD LED's were on.