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This guide assume the fill is being performed in a state where both the upstream and downstream Be windows have holes, and that a fixed Be window exists on the upstream side of the IP and a movable Be window on the downsstream downstream side.

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. Set up the mass flow controller, but leave the flow rate at 0: How to use MKS mass flow controller (DPS
   
   From the Gallery:
5. Verify the oven fill line is connected to the gas bottle of the desired gas type and the flow regulator is closed.:Open the fill valve #1 to evacuate the line and leave open for several minutes then close. 
   1. Gas bottles and flow regulator location:
   2. 
6. Set up to the mass flow controller: How to use MKS mass flow controller (DPS)
7. 1. 
      
8. Open the gas bottle and set the regulator to 10 psig.
9. 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)
10. 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.
    
    From Epics again:
11. Open the fill valve #1 to evacuate the line and leave open for several minutes then close. 
12. Open the fill valve #1 and start flow with the MFC to purge He through the fill line for several minutes.
13. Close the fill valve to stop the flow and evacuate the IP again.
14. If operating the Li oven, follow the E300 procedure to prepare the Li oven for a static fill.

Start the fill:

1. 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 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 a setting of ~0.8 SCFH or ~400 on MFC results ~5 Torr for Hethese 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.

Recovering from faults:

If a single stage in the DPS trips off, the IP pressure should not be effected significantly so the fill valve, oven valves, and oven heaters should remain open or on.  The decision to halt operation of the oven should be made depending on the nature of the fault. The problem should be fixed as soon as possible to regain redundancy in the DPS system.

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