michael.rodruck@LIGO.ORG - posted 10:26, Tuesday 29 January 2013 - last comment - 16:33, Tuesday 29 January 2013(5297)
PSL tripped
The laser shut down earlier today due to a communication failure between the control boxes and the Beckhoff computer. What I think happened is the power to the ethernet to fiber converter for the LVEA control box was lost - this is plugged into an AC outlet and the prongs were barely in, so it probably got bumped. I'll wait until the CDS work is done to bring the laser back up.
Restarted the laser. I had noticed that the diode chiller flow level was slowly decreasing over the past two months, and thought it might be due to clogged filters. I swapped both filters out from the diode chiller but the flow was less than it was before. I increased the flow as high as I could, to 22 lpm, but it has continued to decrease, although it looks like it is slowly settling down.
I included a 60 day trend of the flow rate, which shows that something happened at the end of December which decreased the flow and hasn't stopped. I don't believe it is due to anything we have done, as this occured over holiday.