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- Switch the LIquefier to Manual + Liquefy mode (Manual + Idle mode is also the same because Liquefy/Idle option has no effect when it is in the 'Manual' mode)
- Ensure the dewar pressure alarm threshold is around 0.2 psi (navigate to the Liquefier 'Settings' to check that).
- Set the inlet flow to 60slm: enter 60slm on FC501(A/B)Q (then press enter)
- Option 1: Set the outlet flow for the maximum flow by opening SVV(A/B) and the manual hand valve bypassing the SVN(A/B)
Option 2: Open VJV(A/B), VJVT, open Magnet Bypass control valve to have the flow through the magnet. - Option (1): Open the magic valve NV501A/B completely (~9 turns).
Option (2): Open SV503(A/B) and keep the magic valve (at ~1/2 a turn)
(see pictures on Supply Manifold for the Liquefiers) - Turn ON the cold heads manually on "Helium Compressors" screen
- Move the transfer stinger a few inches up (to avoid touching the bottom).
- It will take about 2 hrs and 30 mins for the cold head temperatures to reach 4 Kelvin.
- Once cold head temperatures reach 4 Kelvin, then gradually close the SVNB-bypass hand valve while watching the Dewar pressure.
Reason: because the Dewar pressure would be ~1psi at this stage and we want to bring the Dewar pressure up so we can transition to have the outflow through SNVB (with the flow controller), and stop the flow through SVVB.
Related to Option 2 in the step (4): We can continue to flow gas through the magnet by monitoring the temperature sensors in the magnet as well as in the Dewars. - Once the Dewar pressure is > 6.5 psi from Step 7, then close SVVB and immediately open SVNB and ensure the FCBQMC is 60slm (FCBQ will also show 60slm).
- Then you will see FCBI starts increasing and should go up to 60slm or, at least 40slm (or above).
- Let it run in this configuration: in-flow 60slm, out-flow 60slm (via SVNA/B), cold-heads are running, mode: run+manual+liquefy
- You should expect ice/frost on Dewar neck during this phase, and you will have to use the heat gun to melt the frost.
- When you start seeing FCBI start going down while FC501B is 60slm, then lower the value of FCBQMC step by step based on the FCBI.
- Once you bring FCBQMC down < 5slm, then check the Liquefier Settings screen to ensure the following values.
- Switch the Liquefier to Run + Auto + Liquefy mode
- Related to Step #5:
Option (1): Bring the magic valve position for optimizing for production ( open ~1/2 a turn)
Option (2): Close SV503 (A/B) and leave the magic valve open ~1/2 a turn (original position) - When the liquid starts accumulating, move the transfer stinger all the way down.