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  1. Select a QT liquefier ("Liq") for the magnet filling. Liq should contain at least 200 L of Helium.
  2. Change the mode of Liq to Auto + Idle.
  3. Change the pressure set point of Liq to 4.0 psi.  It will take >1 hour for the pressure to go down to the set point.
  4. Start to cool down the transfer line by opening VPC and VJVA/B.
  5. Monitor TX1 and wait until it reaches below 100K (for ~10 minutes).  It is normal that TX1 first rises slightly.
  6. Disable the auto control of the MagRetBypass valve.  Open the valve fully.
  7. Open VJVT.  Close VPC.  You now start the transfer to the magnet.
  8. Change the mode of Liq to Manual + Idle.
  9. Open SV501A/B.
  10. Set FC501A/B at 60 SLM.
  11. Turn off all the five cold heads of Liq.  Confirm that the pressure of Liq is increasing.
  12. Wait until the pressure differential (between Liq & Mag) becomes 3.5 psi.
  13. Set FC501A/B at 40 SLM.
  14. Maintain the pressure differential at 3.0-3.5 psi, by adjusting FC501A/B (typically within +-5 SLM).
    1. Also confirm that the magnet level is increasing.
  15. Keep until the magnet level reaches 40% (135 L).
  16. Close VJVA/B.  Open VPC.  Close VJVT.  You now finish the transfer.
  17. Enable the auto control of the MagRetBypass valve.  Change the set point to 1.5 psi if needed.
  18. Change the Liq mode to Auto.
  19. Change the pressure set point of Liq to 6.5 psi.
  20. Wait until the cold-head temperature becomes <10 K.
  21. Change the Liq mode to Liquefy.
  22. Confirm that the Liq pressure stays around the set point (6.5 psi).  If it goes above it, set the outflow (FCA/B) at 40 SLM, wait for 5 minutes, set it back at 2 SLM, and confirm again.

Previous Version

  1. Select a QT dewar for the magnet filling. The dewar should contain at least 200L Helium
  2. Bing the dewar pressure to around 3.5-4 psi by setting the liquefier to Manual+Idle and setting outlet flow to 60 SLM.  This will take around 1 hour (for 6.5 psi to 3.5 psi)
  3. Start to cool down the transfer line by opening VPC and VJVA/B.  Monitor TX1 and wait until it reaches below 100K.
  4. When it is ready, start the transfer to the magnet by following the  sequence 
    1. Fully close the magnet return bypass valve
    2. Open VJVT
    3. Close VPC
    4. Fully Open the magnet return bypass valve
  5. Pserize the dewar by opening SVPA/B to maintain a 3 psi pressure difference between the magnet
  6. monitor the magnet helium level
  7. Stop the transfer when the magnet helium level reaches 40%
    1. Close VJVA/B
    2. Open VPC
    3. Close VJVT
    4. Set the magnet return bypass valve to 1.5 Pid control
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