At approximately 12:33 UTC (4:33 PST), the 35W FE power watchdog tripped, causing the HPO power watchdog to trip ~6 seconds later (see 1st attachment).  Looking at the laser power for the 35W FE shows the MOPA and the NPRO lose power at the same time, thereby causing the watchdog trip (2nd attachment; the little bump in H1:PSL-OSC_PD_AMP_DC_OUTPUT is simply residual light from the still operating HPO hitting the PD, it goes away once the HPO power watchdog trips).  It is unclear what caused the FE to lose output power in this way.  Putting all the signals from the 2nd attachment on one plot and zooming in, it appears the watchdog tripped before the FE lost output power (3rd attachment).  Possibly a glitch in the PSL Beckhoff software?

The PSL was restarted without issue.