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Entry  Mon Jun 30 10:06:39 2014, Steve, Update, VAC, low on pneumatic pressure of vacuum valves runoutofN2.pnglowN2.pngN2d100.png
    Reply  Wed Jul 2 11:47:26 2014, Steve, Update, VAC, broken changeover regulator of N2 supply 
Message ID: 10120     Entry time: Wed Jul 2 11:47:26 2014     In reply to: 10112
Author: Steve 
Type: Update 
Category: VAC 
Subject: broken changeover regulator of N2 supply 

Quote:

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.

 The TESCOM automatic changeover regulator  [ model ACS 012-1011 ] manifold is most likely  clogged. The new one will arrive 8-8-2014

This means that the IFO pressure may go up to a few mTorr when we change cylinder or V1 valve triggered because there is no nitrogen supply.

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