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Entry  Fri Apr 19 14:06:36 2019, gautam, Update, PSL, Innolight NPRO shutoff Screenshot_from_2019-04-19_14-06-11.png
    Reply  Fri Apr 19 20:21:52 2019, gautam, Update, PSL, Innolight NPRO shutoff Screenshot_from_2019-04-19_20-27-04.png
       Reply  Wed Apr 24 16:06:44 2019, gautam, Update, PSL, Innolight NPRO shutoff PMCrefl.png
          Reply  Thu Apr 25 01:03:29 2019, gautam, Update, PSL, MC trans is ~1000 cts (~7%) lower than usual 
          Reply  Thu Apr 25 17:31:56 2019, gautam, Update, PSL, Innolight NPRO shutoff EdwinShutoff20190425.pngEdwinShutdown_zoomOut.png
             Reply  Mon Apr 29 16:25:22 2019, gautam, Update, PSL, PSL turned on again 
                Reply  Fri May 3 12:51:58 2019, gautam, Update, PSL, PSL turned on again 
                   Reply  Mon May 6 10:51:43 2019, gautam, Update, PSL, PSL turned off again NPROshutoff.png
                   Reply  Wed May 8 19:04:20 2019, rana, Update, PSL, PSL turned on again 
                      Reply  Thu May 9 19:50:04 2019, gautam, Update, PSL, PSL turned off again Screenshot_from_2019-05-09_19-49-29.png
                         Reply  Mon May 13 10:45:38 2019, gautam, Update, PSL, PSL turned ON again IMG_7431.JPG
                            Reply  Wed May 15 10:56:47 2019, gautam, Update, PSL, PSL turned ON again 
Message ID: 14599     Entry time: Thu May 9 19:50:04 2019     In reply to: 14597     Reply to this: 14605
Author: gautam 
Type: Update 
Category: PSL 
Subject: PSL turned off again 

This time, it stayed on for ~24 hours. I am not going to turn it on again today as the crane inspection is tomorrow and we plan to keep the VEA a laser safe area for speedy crane inspection.

But what is the next step? If these diode temps maximize the power output of the NPRO, then it isn't a good idea to raise the TEC setpoint futher, so should I just turn it on again with the same settings?

I did not turn the HEPA down on the PSL enclosure. I also turned off the NPROs at EX and EY so now all the four 1064nm lasers in the VEA are turned OFF (for crane inspection).

Quote:

locked PMC at 1900 PT; let's see how long it lasts.

My hunch is that the TECs are working too hard and can't offload the heat onto the heat sinks. As the diode's degrade, more of the electrical power is converted to heat in the diodes rather than 808 nm photons. So hopefully the increased airflow will help

 
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