This morning valve condition: V1, VM1, V4 and V5 valves were closed. IFO pressure rose to 1.3 mTorr
It was caused by low N2 pressure. Our vacuum valves are moved-controlled by 60-70 PSI of nitrogen.
When this supply drops below 50-60 PSI the interlock closes V1 valve. This is the minimum pressure required to move the large valves.
It is our responsibility to check the N2 cylinder pressure supply.
The vacuum valve configuration is back to VAC. NORMAL, CC1 4.8E-6 Torr
PS: Bob says that the second cylinder was full this morning, but the auto-switch over did not happen.
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