PUMPING THE DEWAR
Attach DEWAR to system.!! DO NOT OPEN CAVITY to VACUUM LINES YET!!
Move front panel switch to START. The roughing pump now evacuates the test
When vacuum lines are down to about 5mTor (testport pressure indicator),
wait about 5 minutes and open dewar to detector cavity valve to pump out
If you want to make some leak test, this is the right time (Cf. Leak
Pump on detector cavity for few hours. !! DO NOT LEAVE PUMP UNATTENDED,
since power outage will allow detector cavity to gain pressure and gases.
Close the valve of the dewar.
Front switch: RESET, VENT.
Disconnect Dewar from the pump and pour liquid nitrogen into it.
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