Camilla, TJ

I went to turn on the CO2 lasers to prep for locking today. I found both power supplies on the mechanical room mezzanine needed to have their outputs turned on. For TCSX, I then was able to turn the controller on, turn the key, hit the gate button, then turn on the laser via medm as usual. For TCSY though, the controller complained of a Flow Alarm as soon as the unit was turned on, and turning the key or hitting the gate would not clear it. The flow was reading 2.45gpm according to the paddle wheel flow meter on the floor, and before the vent we were just above 2.5gpm on the floor and 3.4gpm at the chiller. We had reduced the flow of this chiller back in December with Robert (alog81246), so I tried bumping up the flow slightly to 2.6gpm on the floor in the hopes to clear the flow alarm. Now, the flow alarm wasn't present when turning the unit on, but then when I turned the key and hit the gate button, the flow alarm came back.

At this point Camilla and I checked cable connections, tried turning the chassis off and on while waiting a bit, patting our heads while rubbing our bellies, and some other non-fruitful things. Eventually we moved the flow back up to 3.8gpm at the chiller and 2.8gpm at the floor and the flow alarm never showed up. We tried to bring the flow down a bit, but the flow alarm would return. We have no idea why the controller isn't happy with us running the flow at levels that we have been for all of 2025. For now, sorry Crab Nebula.