Reports until 09:17, Thursday 08 November 2018
H1 PSL (PSL)
richard.savage@LIGO.ORG - posted 09:17, Thursday 08 November 2018 - last comment - 11:00, Thursday 08 November 2018(45119)
H1 Laser Room system controller issues

JeffB, RickS

This morning, we hoped to inspect some aspects of the water piping in the Laser Room to prepare for upgrade work planned for Monday.

However, we were unable to get the Laser Room into "Commissioning Mode."

Following the laminated procedure, we were unable to execute the step that calls for enabling the Air Conditioners by pressing the start buttons on the two displays inside the Laser Room.  The displays were dark, as if the controllers were powered off, even though the breakers in the panel on the LVEA wall had been switched on.

Not wanting to cause a large temperature step by running the HEPA fans without the AC units, we abandoned our planned inspection and attempted to restore the system to "Science Mode."

However, we were unable to set the Make-up Fan speed to 20%.  It is currently running at 100%, while we investigate further.

Comments related to this report
richard.savage@LIGO.ORG - 09:35, Thursday 08 November 2018 (45120)
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RobertS, RickS

We went out to investigate the inability to transition to 20% on the make-up air fan.  

Apparently, we had failed to read the laminated procedure carefully enough.  

When going from "Commissioning Mode" to "Science Mode," one needs to stop the make up air fan, then set the speed to 20%.

This is carefully detailed in the procedure.  One just has to be diligent about executing each step of the procedure until this control system is updated.

The system now appears to be in the nominal "Science Mode" state.

jason.oberling@LIGO.ORG - 10:59, Thursday 08 November 2018 (45123)
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After talking with Bubba, we decided that a power cycle was a good first step (as it almost always is).  To this end, after checking the commissioning status with Jenne (they were performing an initial alignment), I went out and power cycled the PSL enclosure AC units and entered the enclosure to visually confirm the status of the AC displays in the Laser Room.  Both displays were active, and when I followed the standard procedure for turning on the ACs (press the ON button on the AC display twice), both displays indicated that the AC units were ON.  I then exited the enclosure and returned it to Science Mode so as not to interrupt commissioning.  I left the ACs ON at the breaker (but OFF on the display).  I watched the enclosure temps for a couple minutes and saw no sign that the ACs remained ON (as Cheryl saw and reported in her alog here), but will continue to check on this throughout the day.  If anyone notices that the PSL enclosure temps are not normal (I believe there's a verbal alarm if the temp sensors at the AC vents read too low), please let me know.

cheryl.vorvick@LIGO.ORG - 11:00, Thursday 08 November 2018 (45124)
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  1. On Tuesday, the AC units resumed their behavior of staying on when the controller shows that they are turned off.
    • I verified this on the controller screen (screen showed that AC was OFF), so I had to flip the breakers to actually turn the AC off.   See Alog 45075. 
  2. Team PSL has not had to use the breakers to stop the AC for quite some time, meaning a number of months. 
    • This would suggest that the controller has more than one operational state, and has again switched to the state where the controller screen shows the AC in one state (OFF) when it's really in another state (ON). 
    • This would also suggest that the symptom where we change numbers on the controller and they appear to change, but when we revisit the setting after a time (usually hours+) we find that the numbers did not actually change.
  3. It would be interesting to look at the reboot history of the controller, to see if there's a recent reboot that may account for the change.