J. Oberling, P. King, T. Sadeki, N. Lecoeuche

This is a catch-up alog to document my involvment with recovering the PSL from the trip caused by last night's power glitch.  I should have been entering these last night as we were recovering the PSL.  I did not think to do so, and therefore left others recovering other parts of the IFO uninformed regarding PSL status.  That's entirely on me and I apologize.

Travis called me at ~10:50pm informing me that the PSL had gone down during the thunderstorm due to an apparent power glitch, so I walked him through restarting it.  On the STAT screen we saw that the NPRO had tripped off, likely due to the glitch.  The chillers were still running nominally and the external shutter was still open, so most of the system was already ready to go and we restarted the laser without issue.  Before trying to lock the PMC, we turned off the FSS and the ISS; the FSS was turned off so it wouldn't constantly be driving the NPRO to attempt to lock the RefCav (which it couldn't do since we had no PMC), and we turned the ISS OFF as, with no PMC there was no light on the ISS PDs, so the loop was oscillating.  This done, we attempted to lock the PMC, but no luck.  As Dave was still recovering from the Dolphin crash and it was nearing the end of Travis's shift, we decided to wait until attempting to lock the PMC.  In the interim I tried to figure out why the PMC wasn't locking.  Unfortunately for me, it took my sleep-deprived brain over an hour to notice the obvious: the PMC PZT was not responding, at all.  So, first things first, I asked Niko (now on shift) to check the PZT HV power supply.  This supply lives up in the mezzanine of the CER, so Niko and I set up a quick buddy system via email for his safety while climbing up and down that steep ladder to the CER mezzanine, and he went to check on the power supply.  He got back to me in ~10 minutes with the attached picture, indicating that the power supply had indeed tripped in the power glitch.  At this point my even further sleep-deprived brain (it was after 2am) failed me completely; I could not remember the correct voltage and current settings for this power supply (they must be entered manually), so I asked that Niko, when he was ready to restart the power supply, call Peter for assistance.  Peter was able to walk Niko through recovering the PMC PZT power supply, as well as the PMC, ISS, and FSS, and this morning the PSL is up and running as normal.

For the record (and for future reference), the correct voltage and current settings for the PMC PZT power supply are posted on the power supply itself.  They are: Vset of 375V (press the Vset button, enter 375, press enter), Iset of 50mA (press the Iset button, enter 50, press enter).  Press the Output On/Off button to enable/disable the power supply output.