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Change the separator flow to 20 SLM (from 7 SLM usually). See this page for instructions → How to control the Separator Return flow
- Wait for 1.5-2.0 hours. Use https://e906-gat1.fnal.gov/data-summary/e1039/target-allv2.php with the parameter "
- Change the separator flow to 25 SLM (See → How to control the Separator Return flow), and send a discord message to the group mentioning that you are changing the separator flow and will fill the fridge soon.
- Change the setting of the gate-valve bypass as follows (See → How to control the Fridge Return flow):
- The auto control is disabled.
- The absolute valve position is 0.08 turns.
- Change the setting of the fridge valve system as follows (on Fridge_Valve_Main.vi):
- The level-probe mode is "CONT" (not "HOLD").
- The Interlock with Heat-Ex Top is enabled.
Open the bypass valve at 2.0 turns. Confirm that the fridge return flow goes up. See → How to Open or Close Fridge Valves
- Open the bypass valve at 3.0 turns.
- Change the separator flow to 30 SLM.
Wait until the Ann-Plate Top resistor goes up to 1400 Ohm, which indicates that the liquid started accumulating. It usually takes 30 minutes from step #3. If it takes longer than 40 minutes, search for unexpected conditions.
- Wait until the nose LHe level reaches 100%. It usually takes 15 minutes from the previous step.
- Wait until the Heat-Ex Bottom resistor goes down from 1400 Ohm and then up. It usually takes 10 minutes from the previous step.
Wait until the Heat-Ex Top resistor goes up to 1400 Ohm, which indicates that the liquid is as high as Heat-Ex Top. It usually takes 10 minutes from the previous step.
Close the bypass valve.
- Usually the software interlock sets it at 0.5 turns automatically.
- Anyway you set it at 0.0 turns manually.
Change the separator flow to 7 SLM.
- Change the setting of the gate-valve bypass as follows:
- The set point for the auto control is 40 Torr.
- The auto control is enabled.
- Change the level-probe mode back to "HOLD" if you changed it in step 5.
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