Common Problems

Problems and Solutions

• Collimator Temperature is Rising
  • If the collimator temperature alarm goes off, call MCC and tell them to turn off the beam. Then call the RC.
  • Don't raise the temperature alarm limits on the collimator. If it's getting warm, something's wrong.
  • Things to check:
    • Is the collimator cooling? Stripchart should show 5 for the Collimator water flow at all times.
    • Is the raster size correct? Correct size is written on white board.
    • Have the Raster quads (Moller quads) been set to the correct values? See strip chart called "RasterQuads" and scale back in time to look for changes to values
    • Are the bpms working? IPM1H04A and IPM1H04E XPOS and YPOS should read out nonzero numbers on the strip chart when beam is on.
    • Is the beam in the right position? See appropriate IPM1H04A and IPM1H04E XPOS and YPOS written on the whiteboard.
    • Is the HallATGT lock enabled? Call MCC and ask if the target lock is enabled
    • How do the ion chamber rates look? Look at the strip chart's history and see if the rates are higher than they were at the same current for recent running
    • How to the radiation levels look? Look at the strip chart's history and see if the rates are higher than they were at the same current for recent running

• Runbird Aq/Parity feedback isn't working
  • We want Aq/Parity feedback running at ALL times during production data taking
  • The most reliable check to see feedback is working is to look at VPITA on runbird and make sure it is changing values every 10sec (when beam is ON).
  • If you see a red box on Runbird or if Aq doesn't update, look at VPITA. If VPITA is changing, feedback is working.
  • You can triple check by looking at the terminal where Aq/Parity feedback is being run from. Every 10sec it will output a text output showing ....HallA Aq... and ....correction... as well as a list of 8 RTP voltage values. If you see these values being updated in the terminal, feedback is still working.
  • However, if a Parity RTP voltage or IA voltage alarm goes off, feedback may be feeding back improperly. A map file may have been changed and the RC should contact the WAC.

• BPM Saturation
  • On panguin and in the alarm handler, we examine bpm11(IPM1C11) and bpm12(IPM1C12) for saturation. If they get near 50,000, they are saturated.
  • If BPMs are saturating and we are running FFB
    • The solution is to call MCC and request an FFB Gain search. OPS should switch FFB off, press a gain search button. And then turn FFB back on and the saturation should go away. It may be necessary to turn off BMW if this process takes a while. It should take OPS just 1min or so, though.
  • If BPMs are saturating and we are NOT running FFB
    • The solution is to call MCC and tell them that iocse9 is in "Feedback Mode" instead of "SEENormalOPS" mode. OPS needs to put iocse9 in "SEENormalOPS" mode for the BPMs to auto gain properly

• Target isn't moving
  • There's a note on the computer that says: Clear Record. Try pressing clear record first.
  • If the target is moving, you will know because the vacuum alarm will go off for a few seconds when it first starts moving.
  • If the target is moving, you can use the hall camera to zoom in on the ladder as see it.

• Moller Quads trip off
  • If the Moller quads trip off, OPS will need to recycle the magnets and return them to their recent setpoints.
  • DOUBLE CHECK OPS. Pull up the RasterQuads strip chart and make sure OPS has returned all the magnet settings to the SAME values they were before the trip. If not, call OPS and tell them they've made a mistake and to set the values back.

• Detector signal goes down on panguin
  • If a detector signal of the left arm or the right are decreases, it probably means a spectrometer magnet has an issue
  • Check the HRS magnets Q1,Q2,Dipole,Q3 on left and right arms as well as septum current. Check the currents and gauss meter readout matches that printed on the sheet of paper hanging to the left of the target operator computer
  • If the magnets look ok, check the detector HV's are still on
  • Call the RC

• HRS Magnet issues
  • If an alarm goes off, check the HRS magnets Q1,Q2,Dipole,Q3 on left and right arms as well as septum current. Check the currents and gauss meter readout matches that printed on the sheet of paper hanging to the left of the target operator computer
  • Sometimes a magnet on the left or right arm trips off. It's possible recycling the magnet and returning it to its set point will work, but call the RC first. Tech-on-call work may need to be done, but only the RC should communicate with the tech-on-call.
  • Sometimes it's just the readout of the current that's the issue. The current readout might say 0, but the magnet gauss meter reading is normal. This means the magnet is still on. You can double check the magnet is still on by looking at detector voltages in panguin, if they are still ~6V at 70uA, the magnets are probably still on.