Troubleshooting

No ion chamber reading? Low ion chamber reading? No phi rotation? Data collection software or detector not responding?

No ion chamber reading

• are the station shutters open?
  After refills W9.STOP.06 will need to be re-opened. W9.STOP.11 has to be opened each time the hutch is interlocked.

• is the port open?
  (look at status monitor or at sign above hutch door)

• If the display shows a steady single line, it means the reading is larger than the maximum 199.9 that can be displayed. Change to a lower gain.

• If there is still no reading you should open up the camera slits to around 1 mm. The drums controlling the slit width adjustment have two dials on either side of a central rail. The outer dial reads in full mm, and the inner dial reads in fractions of mm.

  Proceed to maximise the ion chamber reading by driving the table motors. There should be some reading with the slits set that wide. If it is a faint reading, try using gain x100. Only major disasters may be invoked as a reason for failing to get a reading by now. You should proceed to maximise the reading on CHAMBER2. Reduce the slit widths gradually, and repeat until you have optimised the reading through the slits set at the desired width.

Low ion chamber reading?

• Drive table motors

• Check Theta arm

  This option moves the Theta arm on which the camera table sits. This is infrequently needed to discriminate between the main and side poles of the Wiggler. On moving the theta arm two 'bumps' of intensity should be seen corresponding to x-ray intensity from the two poles of the Wiggler. The higher intensity 'bump' is the one to centre on. Users should not normally have to move the theta arm. However, if after optimising the beam, the intensity is still found to be low, the theta arm should be driven and the ion chamber reading watched carefully to observe the two 'bumps' of intensity. You should then centre on the highest intensity region.

• If the reading is still low then contact a station scientist

No phi rotation

• was phi axis left in 'click' position?

Data collection software or detector not responding

• To reinitialise the CCD: Exit from the data collection program. Go into the Hutch to the detector control crate and exit from the CCD program on the pc. This is done by clicking on the cross in the top right hand corner of the black window. Now restart the program by clicking on the blue Quantum 4 logo and then restart the data collection program on bl96alpha1.

• If the PC in the rack has hung it will be necessary to open the small pull-down door above the keyboard and press the reset button. Exit the data collection software first then reset the PC.

  Important!! Please wait 20-30 secs after the computer has rebooted to allow the virus scan to finish before starting the Quantum 4 software.

• It may also be worth rebooting bl96alpha1. This is done by typing 'shutdown' in a free window. You do not need to log out. The computer will shutdown and reboot automatically. It may prompt you to 'push any button to continue'. This is where you may power off the computer, if needed. The reboot cycle will be complete within a few minutes.