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The temperature went down to room temp with temporary fan in the back. Voltage and current are stable.
Regardless, it will be replaced early next week.
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Koji, Steve
It was a bad experience again with our vacuum system. The valves went crazy as we rebooted the computer. This was required for the swap in of a good 24V power supply.
The IFO was vented to 27 Torr through the annuloses, VA6, V7, Maglev,VM2 and VM1 (VC2 was open too)
I just opened the PSL shutter after a 4 hours pumpdown.
Condition: annuloses are not pumped, the IFO and the RGA are pumped as Atm2 shows
I will be here tomorrow morning to switch over to vacuum normal.
More details later
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Events of the power supply swap:
1, Tested 24V DC ps from Todd
2, Closed V1, VM1 and all annulos valves to create safety net for the reboot. Turbo pumps left on running.
3, Turned computer off
4, Swap power supplies and turned it on
5, Turning the power on of c1vac2 created caos switching of valves. This resulted in a air vent as shown below.
6, VM1 was jammed and it was unable to close. The IOO beam shutter closed and the IFO was venting with air for a few minutes. Maglev did an emergency shut down. TP2's V4 and TP3' V5 closed. RP1 and RP3 roughing pumps turned on, their hose was not connected as usual. The RGA shut down to protect itself.
7, Closed annulos valves, stoped the vent at P1 27 torr as the vacuum control was manually recovered
8, The Maglev and the annuloses were roughed out 500 mtorr . The Maglev was restarted.
9, The IFO pump down followed std procedure from 27 torr. VM1 was moving again as the pressure differential was removed from it.
Remember: next time at atm .....rough down the cryo volume from 27 torr ! |