TJG 8/8/2002
Running at reduced acceleration voltages
To set a reduced acceleration voltage:
- At 60kV, check the Acceleration voltage in the HT control window (V1)
- In the mass control window, check that the High voltage to calculate mass is
equal to V1 (both magnets).
If not, set it and recalibrate the magnets.
- Set the new HT, amd re-check the Acceleration voltage in the HT control window (V2)
- Load the 60kV QP-array(s) into Excel and reduce the values in the ratio V2/V1. Save the new values,
and send them to the equipment.
- Set the High voltage to calculate mass equal to V2 (both magnets).
Set the required mass.
- Check the position of the beam at all focal points. Adjust the deflectors if necessary. Focusing and magnet
calibration should be OK.
Before each change of HT, note in the logbook
- The previous HT (CCV and AQN)
- The High voltage to calculate mass (both magnets)
- The mass factor (both magnets)
- The filenames of the QP-arrays being used
This information will help the next user to switch back to the previous acceleration voltage.
Note that the resolution of the separator falls with the acceleration voltage