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