J. Oberling, C. Gray

At 21:01:51 UTC the PSL NPRO shut off (see attached trend of NPRO diode power, NPRO power, and PSL power watchdog), reason unknown.  The PSL watchdog tripped 3 seconds later at 21:01:54 UTC, so the NPRO definitely shut off first.  After Corey's phone call I drove to the site to reset the PSL.  The only thing I found wrong was that the NPRO power supply was ON, but not sending power to the NPRO (key ON, power supply OFF).  The UPS the NPRO power supply is plugged into did not show an error, and there were no other obvious indications that something went wrong, so I turned the NPRO back ON.  It powered up without issue, and we turned the 35W FE laser on from the LDR.  After fiddling with the PMC and FSS (as usual after a laser shutdown), everything with the PSL was locked and operating properly.  It is still unknown why the NPRO shut off.  At this point I suspect a glitch with the UPS; we have seen this behavior before, where a glitch in the UPS causes the NPRO to shut off with no idication of what went wrong.

At this point we noticed the FSS TPD was down to ~1V, which is getting close to the point where ALS becomes unhappy.  A 7 day trend of the RefCav TPD is attached.  At that rate of decay the FSS might not have lasted until maintenance day on 1-5-2016, so we decided (with M. Landry's permission) to go in and do a quick adjustment of the RefCav alignment.  I will detail that in a follow up alog.