michael.rodruck@LIGO.ORG - posted 13:21, Monday 04 March 2013 - last comment - 17:29, Monday 04 March 2013(5641)
PSL shutdown/restart
The laser shut off over the weekend due to the power watchdog tripping. It looks like I had set the watchdog on the laser when the humidity was relatively high, and once the weather changed the humidity dropped back down and tripped the laser. We really need to look into this since the majority of shutdowns have been due to this humidity issue.
I took the opportunity to increase the current on the pump diodes to get us back to nominal power. The changes made are as follows:
- Diodes 1/2: 50 A to 51 A
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Diodes 3/4: 50 A to 53.5 A
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Diode 3 Temp: 25 C to 23 C
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Diode 4 Temp: 25 C to 22 C
I found that I could increase the power from the diodes by decreasing the temperature, but there was a point where increasing the diode power actually decreased the output of the laser. Instead of trying to maximize power from the diodes I watched the output of the laser and brought it up to 33 W. This is where we were back when the laser was installed.
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I lowered the current on diodes 3/4 to 53 A after I got a bit more power out of diode 3, by decreasing its temperature to 20 C.
Also decreased the AC units to 20 C (unrelated) to try and stabilize room temperature for IO.