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- If it was open, close angle valve VV3201 isolating the plasma beamline from the plasma turbo
- 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 to stop)
- Note - the speed readback on the turbo panel always reads zero
- From the E300 panel - Set Fill Gas #1 to ON
- From the MFC controller - 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
- 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.
- 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:- Open gauge 3108, Press "Turn On"
- Open the "Valve Intlk" panel, and click "Reset Interlocks"
- Reopen valve 3160 to resume beam delivery
- Turn on CC gauges 3130 and 3151
- 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.
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