Since we were working on violin mode damping anyway (aLog 20280), we also tried some ETMX violin damping tuning. At some point, we tripped the ETMX analog PUM current RMS watchdog. We tried setting the H1:SUS-ETMX_BIO_L2_RMSRESET to zero, then back to one (which worked to reset the ETMY watchdog, when we tripped that once or twice). We tried this reset procedure several times, but the watchdog isn't resetting. I don't know enough about this system to diagnose it further, so I await guidance from someone more knowledgeable in the morning. Our low frequency noise is kind of terrible, which might be because it looks like we aren't driving the ETMX L2 stage at all, but we are able to get to the Nominal Low Noise state (the trip happened at the DC Readout state).
Attached is a screenshot of the current state of the ETMX suspension screen, including the tripped L2 RMS watchdog.
Afterwards, we punched in zero again in H1:SUS-ETMX_BIO_L2_RMSRESET. Even though we did not punch in 1 this time, for some reason the current monitor became back active, the watchdogs were untripped. After a minute or so, we set it back to 1 and confirmed that the coils were still active by observing the current monitors.
Another strange thing is that, even though the coils are now active, the screen still shows a red light at the top as Jenne showed in the attachement. This needs to be investigated in the day time tomorrow.
Jenne and I drove down to EX and power cycled the PUM driver. That untripped the watchdog. [Also, I power cycled the AA chassis two slots below the PUM driver by accident. Sorry.]
We've seen this failure mode before: https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=17385
Yes. The Y PUM watchdogs can be reset from MEDM but the Xs cannot.