ryan.crouch@LIGO.ORG - posted 13:54, Monday 26 June 2023 - last comment - 17:53, Monday 26 June 2023(70829)
Lockloss @ 20:40 Possible Power glitch?
All the HEPI and ISI watchdogs tripped at both Ends and we saw the lights flicker in the control room. No issues on CDS, I tried to untrip them after seeing the values were below the trip points, but the HEPIs retripped after a few minutes and the ISIs stayed untripped.
Attached mainsmon channels for EX show a glitch at 13:39 PDT
Here is a zoomed-in plot of the 3 phases for each building, about 5 cycles of the 60Hz shown. I think I can convince myself that the CS glitch was not as great at the EX, EY glitches.
Storms were just SW of us at the time of the lights flickering and although didn't look crazy, the radar shows more sever thunderstorms in the area than anticipated. A series of them appeared to move East and a bit North within the hour.