...
- Open the LI20 Vacuum panel, then open the "DPS Full Schematic" button at the middle of the page
- Verify that the IP is under vacuum. Gauge 3259 should read << 1e-6 Torr.
- 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.
- This is how the DPS looks under nominal operation:
- This is how the DPS looks under nominal operation:
- Open the "E-300 oven" panel from LI20 Experiment page. See below for details. The figure shows the important items:
- You will use the "Fill Gas #1" ON and OFF buttons to start and stop gas flowing to the IP
- "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.
- The "EPS RESET" button will reset the EPS faults (if the faults have been cleared) and allow you to flow gas again.
- The 10 Torr gauge reading gives the IP pressure
- Open the "Gas jet control panel" from the LI20 Experiment page
- Press MAX beside "Set foreline pump speeds"
- Click "Gas Type..." and at the bottom of the page, select the gas species that you will use.
- Note - there is no hydrogen calibration, so use Helium instead.
- Start a strip tool by clicking "Pressure Strip Chart" from the gas jet panel
- Or you can do this by loading the file: DPS_Gasjet_Pressures.stp
- Find the VGCM:LI20:M3203:PMONRAW pressure - this is the 10 Torr capacitance manometer gauge that will provide the IP pressure.
- Set up the mass flow controller, but leave the flow rate at 0 for now: How to use MKS mass flow controller (DPS
- Abbreviated instructions (assuming everything has already been set up for you):
- Go to 192.168.2.155 in a browser on PC96660
- Go to the "plot" panel
- Change "Analog" to "Digital"
- Use the "Flow setpoint" to change the flow rate
From the Gallery:
- Go to 192.168.2.155 in a browser on PC96660
- Abbreviated instructions (assuming everything has already been set up for you):
- Verify that the Fill line #1 is connected to the gas bottle of the desired gas type:
- Gas bottles and flow regulator location:
- Open the gas bottle and set the regulator to 10 psig. Open the in-line valve after the bottle.
- Read the gas bottle pressure and ensure that there is enough gas to last for the intended fill.
- Previous measured rate of He usage at 5 Torr IP pressure = 165 psi/day (one full 2500 psi bottle drained in ~15 days)
- If using hydrogen, you need to start a nitrogen purge to increase the pumping efficiency:
- 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
- From Epics - open the "Gas Jet Control" panel from LI20 Experiment page
- Change the value of "US1 purge gas" and "DS1 purge gas" to ON
- 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
- 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: - Inform ACR that you are going to start the gas fill in the S20 IP
- Close the Beryllium window valve - VV3208
- Open the fill valve #1 (from the E300 oven panel - set to ON)
- From the MFC controller - start flow at set the "Flow setpoint" to a low level (30) to purge gas through the fill line for several minutes.
- You may only see a small change in the vacuum level
- Close the fill valve (Set to OFF) to stop the flow and wait for several minutes for the IP to evacuate again.
- If operating the Li oven, follow the E300 procedure to prepare the Li oven for a static fill.
...
- If it was open, close angle valve VV3202 isolating the plasma beamline from the plasma turbo
- Close valve FV-PB on the foreline of the Picnic Basket. Turn off Picnic Basket turbo
- Open Fill valve #1
- Adjust the "Flow setpoint" on the MFC to reach the desired fill pressure. There is a slow response so make changes slowly.
- In previous tests these set points were used with the MFC:
- Helium at 5 Torr = 420
- Argon at 5 Torr = 130
- Hydrogen at 5 Torr = 580
- In previous tests these set points were used with the MFC:
- 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.
- Continue to monitor the IP pressure and make minor adjustments to the flow rate if necessary.
- To adjust the pressure, simply increase or lower the setpoint on the MFC.
...
- If using the Li oven, follow appropriate procedures to shut down and secure the oven
- When ready to drain the He gas - close the fill valve. The IP pressure will drop at an initial rate of ~1 Torr/min.
- Set the flow rate on the MFC to zero.
- Open valve FV-PB on the foreline of the Picnic Basket to aid in the pump down
- Start the PB turbo when the IP pressure is below 1 Torr.
- Close the valve on the gas bottle.
If done for the day: - Open the DS Beryllium window valve VV3208 after the IP pressure is <<1 Torr. (Password is E200)
- Set the gas type back to Nitogen (From the gas jet panel)
- Set the purge gas to OFF (From the gas jet panel), and close the valve on the N2 6-pack
...