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Step-by-step guide

Setup procedure:

From EPICS:

1. Verify vacuum conditions in the IP of approximately 1e-6 Torr.
2. Verify both US-DPS and DS-DPS pumps are running and operating as normal.  Also check VPIO:LI20:3164 to ensure the ion pump is on.
   1. This is how the DPS looks under nominal operation:
   2. 
3. Start a strip tool and load the file: DPS_Gasjet_Pressures.stp
   1. Find the VGCM:LI20:M3203:PMONRAW pressure - this is the 10 Torr capacitance manometer gauge that will provide the IP pressure.
4. Open the "E-300 oven" panel from LI20 Experiment page. See below for details. The figure shows the important items
   1. You will use the "Fill Gas #1" ON and OFF buttons to start and stop gas flowing to the IP
   2. "Gas 1 & 2 Supply" tells you if the the EPS system is allowing the gas to flow or not. "On" = good
   3. The "EPS RESET" button will reset the EPS faults (if the faults have been cleared) and allow you to flow gas
      
   4. The 10 Torr gauge reading gives the IP pressure
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5. Set up the mass flow controller, but leave the flow rate at 0 for now: How to use MKS mass flow controller (DPS
   
   From the Gallery:
6. Verify the oven fill line is connected to the gas bottle of the desired gas type:
   1. Gas bottles and flow regulator location:
   2. 
      
7. Open the gas bottle and set the regulator to 10 psig.
8. Read the gas bottle pressure and ensure that there is enough gas to last for the intended fill.
   1. Previous measured rate of He usage at 5 Torr IP pressure = 165 psi/day (one full 2500 psi bottle drained in ~15 days)
9. Verify gas bottle on fill line #2 is closed and that the fill valve for this line is closed. Ensure that the IOTA controller in FKG20-24 is turned OFF.
10. If using hydrogen, you need to start a nitrogen purge to increase the pumping efficiency
11. 
    
    From Epics again:
12. Open the fill valve #1 to evacuate the line and leave open for several minutes then close. Inform ACR that you are going to start the gas fill in the S20 IP
13. Open the fill valve #1 and start flow with the MFC to purge He
14. From the MFC controller - start flow at a low level (50) to purge gas through the fill line for several minutes.
15. Close the fill valve to stop the flow and evacuate the IP again.
16. If operating the Li oven, follow the E300 procedure to prepare the Li oven for a static fill.

Start the fill:

1. Close If it was open, close angle valve VV3202 isolating the plasma beamline from the plasma turbo
2. Close valve FV-PB on the foreline of the Picnic Basket. Turn off Picnic Basket turbo
3. Close the Beryllium window valve VV3208 
4. Adjust the MFC to reach the desired fill pressure. There is a slow response so make changes slowly.
   1. In previous tests these set points were used with the MFC:
      1. Helium at 5 Torr = 420
      2. Argon at 10 Torr = 265
      3. Hydrogen at 5 Torr = 580
5. It will likely take 5-10 minutes for the pressure to approach the pressure setpoint. Make small changes and wait for 5-10 minutes for the pressure to stabilize before proceeding with more adjustments.
6. Continue to monitor the IP pressure and make minor adjustments to the flow rate if necessary.
7. To adjust the pressure, simply increase or lower the setpoint on the MFC.

Drain the IP:

1. If using the Li oven, follow appropriate procedures to shut down and secure the oven
2. When ready to drain the He gas - close the fill valve. The IP pressure will drop at an initial rate of ~1 Torr/min.
3. Open valve FV-PB on the foreline of the Picnic Basket to aid in the pump down
4. Start the PB turbo when the IP pressure is below 1 Torr.
5. Close the valve on the gas bottle.
6. Open the DS Beryllium window valve VV3208 after the IP pressure is <<1 Torr.

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