R. Short, F. Clara, S. Dwyer

In the ongoing effort to diagnose the source of the glitches seen in the PSL, we decided to try moving the NeoLase control box in the PSL racks back to rack power, essentially undoing what was done in alog79593, and observe any changes in the glitch behavior. While H1 was unlocked during the commissioning window this morning, I shut down the PSL in a controlled manner (in order of ISS, FSS, PMC, AMP2, AMP1, NPRO), then Fil switched CB1 back to rack power, and I brought the system back up. When back in the control room, we very quickly noticed glitching in the NPRO output power channel as we've seen before, and after locking the RefCav, the FSS glitches also returned. Deciding this wasn't the solution we were looking for (and concluding it probably wouldn't have changed anything in the first place), I took the PSL down again for Fil to switch back to the bench-top power supply, then brough it back up all without issue. Fil also took the opportunity to install a longer cable for this power supply to reduce the trip hazard potential next to the PSL racks. This closes WP 12133.

I'm tagging DetChar since this separate power supply was noted to have helped reduce a 9.5Hz comb seen in DARM, but I'll reiterate that functionally nothing here has changed and CB1 remains on its own power supply.