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OVC Pumping

Mingyu (Charles) Li edited this page Jul 19, 2021 · 2 revisions

Turning off the OVC pump

The OVC turbo pump (the one after the P3 gauge) and its backing valve V31 can be turned off after the fridge operates under ~50 K. Then the roughing pump (near valve B) and its valve V30 can also be turned off.

Never turn off the roughing pump first!

The procedure is:

  • Turn off V31
  • Turn off the OVC turbo pump, wait a few minutes for it to spin down and come to stop
  • Turn off V30
  • Last turn off the roughing pump.