Flipper

From PREX Wiki
Jump to: navigation, search

HALLA instructions
  • Flip Insertable Half Wave Plate (IHWP) state
    • to flip IHWP state, will have to inform other halls of intention to flip state first. Then call MCC and ask them to flip the insertable half wave plate state. They will turn the beam off and in the parity controls screen you will see the IHWP state go from in->out or from out->in.
    • Update 08/25/2020: Hall C will request IHWP flip every 8 hours, if Hall C notifies us when they are ready for the IHWP change, within an hour we comply. For example, if we are close to finishing a slug (let's say we have 3.7C) we will take data until we get to 4C and then change. Make sure to inform other halls in advance before the flip.
    • Note: After the IHWP state has been changed, the parity alarms will go off until the voltages are set correctly.
    • Then (after IHWP is in new desired state), in a terminal go to ssh apar@adaq2, then cd ~/feedback2019, then run ./FlipPCValues within the directory to set the voltages correctly
      • It will ask if you want to increase the slug number, say y for yes. It will ask if you've stopped the run, make sure you have (both Parity DAQ and Compton DAQ), then say y for yes. It will ask if you've observed the IHWP state change, go to parity control screen and check the IHWP state has changed, if so, then type y for yes.
    • Double check voltages are correct: on apar@adaq2, in /feedback2019, run ./checkPCvalues The output should tell you the voltages are good, otherwise call an expert.
    • Update the slug number and IHWP state on the white board, write down the time of flip and first run number for new slug.
    • Check the values against the table in Parity Checks
    • Go to the parity alarm handler and if a parity alarm is red but says OK, click it twice (it will say 60sec and then it will be green). If it turns green again after two clicks, all is well. Do not pause or turn off the alarm handler!!!
    • if alarms go off and values don't match those in table, call an Expert

HALLC instructions

December:

  • Flip Insertable Half Wave Plate (IHWP) state
    • to flip IHWP state, will have to inform other halls of intention to flip state first. Then call MCC and ask them to flip the insertable half wave plate state. They will turn the beam off and in the parity controls screen you will see the IHWP state go from in->out or from out->in.
    • Then (after IHWP is in new desired state), in a terminal go to ssh apar@adaq2, then cd ~/feedback2019, then run ./FlipPCValuesHallC within the directory to set the voltages correctly
    • It will ask if you want to increase the slug number, say n for no. It will ask if you've stopped the run, make sure you have (both Parity DAQ and Compton DAQ), then say y for yes. It will ask if you've observed the IHWP state change, go to parity control screen and check the IHWP state has changed, if so, then type y for yes.
    • Double check voltages are correct: on apar@adaq2, in /feedback2019, run ./checkPCvaluesHallC The output should tell you the voltages are good, otherwise call an expert.
    • Check the values against the table in Parity Checks

January: https://logbooks.jlab.org/entry/3767296



Special note for slugs 24,25
  • For slug 24 and 25 on 8/1/2019, use ./CancelPCValues and ./checkCancelPCValues
    • to flip IHWP state, will have to inform other halls of intention to flip state first. Then call MCC and ask them to flip state.
    • Note: After the IHWP state has been changed, the parity alarms will go off until the voltages are set correctly.
    • Then (after IHWP is in new desired state), on apar@adaq2, in ~/feedback2019/CancelFlip, run ./CancelPCValues to set the voltages correctly
    • Double check voltages are correct: on apar@adaq2, in /feedback2019/CancelFlip, run ./checkCancelPCvalues The output should tell you the voltages are good, otherwise call an expert.
    • Update the slug number and IHWP state of the white board, write down the time of flip and first run number for new slug.
    • Double check AposV which has been modified: Parity Alarm for AposV will still be going off. It is OK to silence it ONLY for these slugs as long as for IHWPin, AposV=15 and for IWHPout, AposV=-237.