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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. Open the LI20 Vacuum panel, then open the "DPS Full Schematic" button at the middle of the page
   1. Make sure that you can see the full schematic
2. Verify that the IP is under vacuum. Gauge 3259 should read << Verify vacuum conditions in the IP of approximately 1e-6 Torr.
   
3. Verify both US-DPS and DS-DPS pumps are running and operating as normal. 
   1. Also check
   VPIO:LI20:3164 to ensure
   1. that the ion pump 3164 is on (The icon the left of valve 3160 is green).
   2. Verify the watcher is running
      1. Click "DPS Status Monitor" at the lower right of the vacuum schematic
      2. Confirm the Watcher status is green/on
   3. This is how the DPS looks under nominal operation:
      
      
4. Set the 10 Torr gauge set points to1 Torr above the desired static fill pressure
   1. Open gauge panel by clicking on the gauges below the text "M3201, M3202, M3203"
   2. Click "Detailed gauge info..." for the 10 Torr gauge
   3. Click "More..." on the PSTAT 1 (RELAY 5) line
   4. Enter a new setpoint that is ~1 Torr above your desired fill pressure.
5. Open the "E-300 oven" panel from LI20 Experiment page. See below for details, but don't click on anything yet. 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" will allow you to open the fill valve.  "Off" means there is a problem.
   3. The "EPS RESET" button will reset the EPS faults (if the faults have been cleared) and allow you to flow gas again.
      
   4. The 10 Torr gauge reading gives the IP pressure
      Image Added
      
      
6. Open the "Gas jet control panel" from the LI20 Experiment page
   1. Press MAX beside "Set foreline pump speeds"
      
   2. Click "Gas Type..." and select the gas species that you will use on the bottom of the page that opens. Verify that all gauges change to the gas type you selected.
      
      1. Note - there is no hydrogen calibration, so use Helium instead.
7. Start a strip tool by clicking "Pressure Strip Chart" from the gas jet panel
   1. Or you can do this by loading
   Start a strip tool and load
   1. the file: DPS_Gasjet_Pressures.stp
   2. Find the VGCM:LI20:M3203:PMONRAW pressure - this is the 10 Torr capacitance manometer gauge that will provide the IP pressure.
8. Set up the mass flow controller, but leave the flow rate at 0 for now: How to use MKS mass flow controller (DPS
   1. Abbreviated instructions (assuming everything has already been set up for you):
      1. Go to 192.168.2.155 in a browser on PC96660
         
      2. Go to the "plot" panel
      3. Change "Analog" to "Digital"
      4. Use the "Flow setpoint" to change the flow rate
         
         From the Gallery:
9. Verify the oven fill line that the regulator labeles "Fill line #1" is connected to the gas bottle of the desired gas type and the flow regulator is closed.:
   1. Gas bottles and flow regulator location:
   2. 
   Open the fill valve #1 to evacuate the line and leave open for several minutes then close. 
   1. 
      
10. Open the gas bottle and set the regulator to 10 psig. Open the in-line valve after the bottle.
11. 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)
12. If using hydrogen, you need to start a nitrogen purge to increase the pumping efficiency:
    1. Open the nitrogen 6 pack main valve and ensure that there is ~10 PSIG pressure on the regulator. Check that the other in-line valves are open
    2. From Epics - open the "Gas Jet Control" panel from LI20 Experiment page
    3. Change the value of "US1 purge gas" and "DS1 purge gas" to ON
       1. You should verify that the purge gas is flowing by opening:  DPS Full Schematic → US1 and DS1 roughing pumps → More..., and read the "N2 Flow" PV. It should be reading ~4 Pa.m³/s
13. Verify gas bottle on fill line #2 is closed and that the fill valve for this line is closed.
14. Ensure that the IOTA controller in at the top of FKG20-24 22 is turned OFF. (Power button will be dark)
15. Check that the 1000 and 10 Torr gauges in FKG20-22 (elevation 29/30) are reading zero. If they are not, perform a manual zero.
    
    From Epics again:
16. Inform ACR that you are going to start the gas fill in the S20 IP
17. From the LI20 vacuum window - Close the Beryllium window valve -  VV3208 
18. From the E300 panel - Set Fill Gas #1 to ON
    
19. From the MFC controller - set the "Flow setpoint" to a low level (30) to purge gas Open the fill valve #1 and set flow rate on the flow regulator to 0.1 SCFH to purge He through the fill line for several minutes.
    1. You may only see a small change in the vacuum level
20. From the E300 panel - Set Fill Gas #1 to OFF Close the fill valve to stop the flow and evacuate wait for several minutes for the IP to evacuate again.
21. 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 VV3201 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 (under the FV-PB valve). Wait for 5 min for turbo to stop (the speed readback immediately goes to zero, but it takes some time for the turbo
3. Close Beryllium window valve VV3208
4. to stop)
   
   1. Note - the speed readback on the turbo panel always reads zero
5. From the E300 panel - Set Fill Gas #1 to ON
6. From the MFC controller - Adjust the "Flow setpoint" on the MFC Adjust the flow regulator to reach the desired fill pressure.
   1. There is a slow response so make changes slowly.
   2. In previous tests a setting of ~0.8 SCFH results ~5 Torr for Hethese set points were used with the MFC:
      1. Helium at 5 Torr = 420
      2. Argon at 5 Torr = 130
      3. Hydrogen at 5 Torr = 580
7. 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.
8. NOTE: When the US1 gauge rises above 1e-3 Torr, it will trip off all of the cold cathode gauges on the US side of the DPS. This will trip the 3160 valve interlock and shutter the beam. This can also happen on the downstream side, although the pressure rarely rises high enough to trip this off.
   To recover:
   1. Open gauge 3108, Press "Turn On"
   2. Open the "Valve Intlk" panel, and click "Reset Interlocks"
   3. Reopen valve 3160 to resume beam delivery
   4. Turn on CC gauges 3130 and 3151
9. Continue to monitor the IP pressure and make minor adjustments to the flow rate if necessary.
10. 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 valveFrom the E300 panel - Set Fill Gas #1 to OFF. The IP pressure will drop at an initial rate of ~1 Torr/min.
3. Set the flow rate on the MFC to zero.
4. Open valve FV-PB on the foreline of the Picnic Basket to aid in the pump down
5. Start the PB turbo when the IP pressure is below 1 Torr.
6. Close the valve on the gas bottle.
   
   If done for the day:
   
7. Open the DS Beryllium window valve VV3208 after the IP pressure is <<1 Torr. (Password is E200)
   
8. Set the gas type back to Nitogen (From the gas jet panel)
9. Set the purge gas to OFF (From the gas jet panel), and close the valve on the N2 6-pack

To change gas types:

1. Use the above procedureto stop the gas flow, set the MFC to zero, and restart the PB turbo.
   
2. Allow the PB turbo to run while you swap gas bottles to fully evacuate the IP.
3. Follow the instructions in the setup procedure to change the gas type on the gas jet panel and MFC, and change the bottle (starting at step 6)
   
4. Continue to follow the steps in the "setup procedure" and "start the fill"

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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