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Reports until 19:18, Tuesday 12 February 2019
H1 PSL (PSL)
richard.savage@LIGO.ORG - posted 19:18, Tuesday 12 February 2019 - last comment - 20:39, Tuesday 12 February 2019(46917)
PSL chiller back on-line (finally)

PeterK, RickS with help from Patrick, Filiberto, Mark, et al.

After Peter swapped in the spare chiller pair (Crystal and Diode), and moved the hardware for reducing the pressure of the Crystal chiller loop (valve and fittins), we had a small leak at the supply side of the Crystal chiller.  We found that two of the  SS 3/4 straight pipe thread fittings were seized, and we were were thus unable to eliminate the leak.

We were forced to switch back to the Crystal chiller that was operating earlier today (it was the Diode chiller that failed).  However, after plumbing it in, we found that the controller failed to initialize.

We swapped in the controller from the spare Crystal chiller, the one with the seized water fittings, and we now seem to be back in business.  

The PSL is back on-line, servos are locked, etc.

We need to a) order the supply side output connector for the spare crystal chiller from Termotek and b) order a replacement controller for the original chiller (that is now in service), and c) make sure we have enough spare parts - controllers, etc.

Comments related to this report
craig.cahillane@LIGO.ORG - 19:31, Tuesday 12 February 2019 (46919)
The laser frontend watchdogs tripped again after about 15 minutes of IMC locked. Posted some relevant medm screens.
Images attached to this comment
keita.kawabe@LIGO.ORG - 20:39, Tuesday 12 February 2019 (46920)

Peter called in to diagnose PSL over the phone.

I first pressed "reset" in the STATUS screen where "INTERLOCK OK" was red.

Then I turned on the NPRO, and then 70W amplifier, but the NPRO tripped after a while.

I pressed reset in the STATUS screen again, turned on NPRO, waited for a while without turning on 70W amplifier, and the NPRO tripped again.

In CHIL_DIAG screen, Diode Chiller temperature was 30.7C though the set point was 20C. Xtal chiller was good. (First attachment.)

I left PSL off, turned off auto locker for PMC, FSS and ISS. (Second attachment.)

When I got back to STATUS screen, Interlock OK was not red, but DB heatsink overtemp in Frontend section was red. (Third attachment.)

Peter will investigate tomorrow.

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