Restarting the DPS pumps is complicated by the nature of the foreline setup, but is generally accomplished by first starting the roughing pump to generate backing pressure on a turbo, then starting the turbo.

Complications to this are:

  1. Some stages don't have a backing pump, or have multiple options
  2. If the beamline is already under vacuum then the procedure is different


IMPORTANT NOTE:  Use extreme caution when changing the foreline valve states as it is possible to accidentally partially vent the beamline if you open a valve in an incorrect configuration.

If you are not comfortable with recognizing the state of the foreline system then don't touch it!


Table of contents:

Starting or Restarting the DPS pumps when the beamline is under vacuum

Assumed starting state:

  • One or more of the turbopumps are stopped
  • The foreline valve for the stopped turbopump(s) are closed
  • You have checked the turbopump and roughing pump status pages for any active warnings, alarms, or other problem indicators
    • (Click "More..." from each pump control panel and look around)
    • Click "Reset" to clear errors
  • The beamline is below atmospheric pressure.


The DS1, DS2, US1, and US2 stages all have roughly the same starting procedure. 


Steps to restart 3291:DS2 stage

  1. Stop the DPS watcher (Physics Apps → GOTO Watcher → Hit "Stop" on the Diff. Pumping line
  2. Open the full DPS vacuum schematic by selecting the "DPS full schematic" button on the LI20 Vacuum page in FACEThome.
  3. Start the roughing pump:
    1. Open the 3291:DS2 roughing pump panel by clicking on the roughing pump icon above the "DS Stage 2" box.
    2. Click "Run". The status should change to "RUN", the power and speeds should increase and the foreline pressure (VGPR:LI20:F3259:DS1) pressure should start to drop.
      1. If the pump does not start, then check if there are any error messages in the "More..." panel. If so, not the error in the elog and press "Reset" on the main roughing pump panel. Sometimes hitting reset multiple times is required so don't give up to soon.
      2. If the error really won't reset, then you can try to power cycle the pump to clear the error. More details in another section.
  4. Start the turbopump:
    1. Open the 3291:DS2 turbopump panel by clicking on the turbopump icon above the "DS Stage 2" box
    2. Click "Run". The status should change to "RUN" and the speed should increase (slowly)
    3. Watch the speed of the turbopump
  5. Open the FV-DS2 foreline valve once the speed is >5000 RPM. You will see a slight spike in the beamline pressure, but it should pump back down very quickly.
    1. Clear the foreline valve interlocks by opening the "Foreline Vlv Intlks..." panel on the LI20 vacuum page, or from the full vacuum schematic, and click "Reset Interlocks".
    2. Click the FV-DS2 valve icon on the path between the turbo and roughing pump.
    3. Click "Open" use the "Position" readback to verify the valve state.
    4. Note: If the foreline valve keeps closing itself, the interlock is likely being tripped. You can temporarily bypass the interlock to get the valve open.
      1. Open the "Foreline Vlv Intlks..." page, click "More" beside the DS2 line, click "Set bypass". Click "Reset Interlocks"
      2. Open the valve. Once the pressure drops back down to the 1e-3 range, then click "Clear Bypass" again.
  6. Verify that the beamline pressure pumps down as expected.
  7. Confirm that the PB turbo is either running, or that the FV-PB valve is closed.
  8. Restart the watcher, unless you have more pumps to start.

Note: Watch the status of the foreline valves and turbopump for a few seconds after you try to make a change. The DPSvacWatcher may work against you and turn off pumps or close valves, depending on what state the system is in. If it does, then try again (the watcher has a built in delay before it redoes the same action), or temporarily stop the watcher.

    1. Go to "Home Screen..." → "Matlab GUIs..." →"GOTO Watcher..." → "stop"
    2. If you want the alarm to not go off in ACR then you should click on "Watching" to set it to Bypassed first.
    3. After you have restarted the pumps, then restart the watcher by clicking "start" and set the status back to "Watching". The status circle should stay green if the watcher is running.


Steps to restart 3259:DS1, 3171:US1, or 3151:US2 stages

The steps are the same as above, swapping the 3291:DS2 id's for 3259:DS1, 3171:US1, or 3151:US2.


Steps to restart 3130:US3 and 3108:US4

  1. These pumps do not have their own dedicated backing pumps, so they can be run as long as the beamline is under vacuum. To restart, just open the turbopump panel for each pump and select "Run".
  2. Open the FV-US3a foreline valve once the 3130:US3 pump speed is > 5000 RPM.

Ensure all gauges are operating

  1. If any CC gauges remain off, then open the gauge panel and manually turn on the Cold Cathode HV.


Ensure the valve 3172 is open when the US-DPS and DS-DPS are both operating nominally.

  1. Ensure that both the 3171 and 3259 gauges are reading nominal pressure (i.e. <1e-7 Torr)
  2. Click on the valve 3172 symbol from the LI20 vacuum schematic page
  3. Click "Enable: Valve Cntrl"
  4. Password is E200
  5. Press "Open", and confirm the valve opens.


Confirm that all pumps are running the way you think that they should be after several minutes.


Starting a DS-DPS pump when the beamline is at atmosphere

Important notes:

  • The beamline windows are designed to only ever have atmospheric pressure applied from one side - from the IP side.  So this means that the DS-DPS can be safely pumped down when the IP is vented and the DS window valve (3208) is closed.  But not the other way around.
  • Do not use this procedure if the beamline is already under vacuum.


Assumed starting state:

  • All pumps are stopped,
  • The beamline is at atmospheric pressure,
  • The Be windows are in tact and inserted in the beamline (unless you want to also pump down the IP).
  • You have checked the pump status pages for any active warnings, alarms, or other problem indicators, and
    • (Click "More..." from each pump control panel and look around)
  • You know what you are doing, or at least you have a vague idea.


Steps to pump down the DS-DPS beamline using 3259:DS1 stage:

  1. Stop the DPSvacWatcher else this will not work
    1. Go to "Home Screen..." → "Matlab GUIs..." →"GOTO Watcher..." → "stop"
    2. If you want the alarm to not go off in ACR then you should click on "Watching" to set it to Bypassed first.
  2. Open the full DPS vacuum schematic by selecting the "DPS full schematic" button on the LI20 Vacuum page in FACEThome.
  3. Ensure that the beamline valves are set the way that you intend them to be.  Typically valves 3208 and 3250 will be closed so the IP area and dumpline will be pumped out independently.  However, the dumpline may be pumped out through the DS-DPS pumps if VV3250 is open.
  4. Close the FV-DS2 foreline valve and open the FV-DS1 foreline valve.  Since the beamline is vented there shouldn't be any significant pressure differentials.
    1. To close or open the foreline valves:
      1. Select the valve icon on the path between the turbos and roughing pumps.
      2. Use the "Open" and "Close" button and use the "Position" readback to verify the valve state.
  5. Start the rouging pump:
    1. Open the 3259:DS1 roughing pump panel by clicking on the roughing pump icon above the "DS Stage 1" box.
    2. Click "Run". The status should change to "RUN", the power and speeds should increase and the foreline pressure (VGPR:LI20:F3259:DS1) and beamline pressures should start to drop.
  6. Wait until the foreline pressure (VGPR:LI20:F3259:DS1) reads under 1 Torr, then you can start the turbo
  7. Start the turbo:
    1. Open the 3259:DS1 turbopump panel by clicking on the turbopump icon above the "DS Stage 1" box
    2. Click "Run". The status should change to "RUN" and the speed should increase (slowly)
  8. Watch the pressure drop.
  9. Then start stage 2 using the same procedure that is used in the section "Starting the DS-DPS pumps when beamline is under vacuum".
  10. Restart the DPSvacWatcher and don't forget to switch it off from "Bypassed" if you had changed it.


I assumed here that you would use the DS1 stage to pump down, but you could alternatively use the DS2 stage if you want.


Legend

These are the clickable icons on the Epics vacuum schematic that will open to give you more info or allow you to start or stop a pump.


Overview of the DS-DPS

This is the section of the vacuum system relevant to the DS-DPS.  You must open the "DPS Full Schematic..." to see all the pumps and valves.



Starting a US-DPS pump when the beamline is at atmosphere

Important notes:

  • The beamline windows are designed to only ever have atmospheric pressure applied from one side - from the IP side.  So this means that the US-DPS can be safely pumped down when the IP is vented and the US window is installed.  But not the other way around.
  • Do not use this procedure if the beamline is already under vacuum.


Assumed starting state:

  • All pumps are stopped,
  • The beamline is at atmospheric pressure,
  • You have checked the pump status pages for any active warnings, alarms, or other problem indicators, and
    • (Click "More..." from each pump control panel and look around)
  • You know what you are doing, or at least you have a vague idea.


Steps to start 3171:US1 stage and pump down the beamline:

  1. Stop the DPSvacWatcher else this will not work
    1. Go to "Home Screen..." → "Matlab GUIs..." →"GOTO Watcher..." → "stop"
    2. If you want the alarm to not go off in ACR then you should click on "Watching" to set it to Bypassed first.
  2. Open the full DPS vacuum schematic by selecting the "DPS full schematic" button on the LI20 Vacuum page in FACEThome.
  3. Ensure that the beamline valves are set the way that you intend them to be.  Typically valves 3160 and 3250 will be closed - 3208 (the DS Be window valve) is currently not sealing due to holes so this is now always open. The IP area and dumpline will be pumped out independently.  However, the dumpline may be pumped out through the DS-DPS pumps if VV3250 is open.
  4. Close the FV-US2 foreline valve and open the FV-US1 foreline valve.  Since the beamline is vented there shouldn't be any significant pressure differentials.
    1. To close or open the foreline valves:
      1. Select the valve icon on the path between the turbos and roughing pumps.
      2. Use the "Open" and "Close" button and use the "Position" readback to verify the valve state.
  5. Start the rouging pump:
    1. Open the 3171:US1 roughing pump panel by clicking on the roughing pump icon above the "US Stage 1" box.
    2. Click "Run". The status should change to "RUN", the power and speeds should increase and the foreline pressure (VGPR:LI20:F3171:US1) and beamline pressures should start to drop.
  6. Wait until the foreline pressure (VGPR:LI20:F3171:US1) reads under 1 Torr, then you can start the turbo
  7. Start the turbo:
    1. Open the 3171:US1 turbopump panel by clicking on the turbopump icon above the "US Stage 1" box
    2. Click "Run". The status should change to "RUN" and the speed should increase (slowly)
  8. Watch the pressure drop.
  9. Then start stages 2, 3 and 4 using the same procedure that is used in the section "Starting the US-DPS pumps when beamline is under vacuum".
  10. Restart the DPSvacWatcher and don't forget to switch it off from "Bypassed" if you had changed it.


I assumed here that you would use the US1 stage to pump down, but you could alternatively use the US2 stage if you want.

Legend

These are the clickable icons on the Epics vacuum schematic that will open to give you more info or allow you to start or stop a pump.


Overview of the US-DPS

This is the section of the vacuum system relevant to the US-DPS.  You must open the "DPS Full Schematic..." to see all the pumps and valves.


IP Area Vacuum