GEM HV controls
<<SBS Main<< HOW TOs (BigBite Spectrometer)
Shifters can only turn HV on or off.
The high voltage for the GEMs shall be OFF for all initial beam tuning operations to the Hall. The GEMs may be powered on, once an acceptable beam profile is established. Only GEM experts should change the GEM HV settings. The high voltage for the GEMs is controlled separately for INFN and UVa. The slow controls should be already up on hadesk9. If they are not open, the control GUI can be opened by typing in a terminal on any hadesk computer (preferably hadesk9):
ssh -Y aslow@adaqsc go_hv
The INFN and UVa GEMs are under ”BB”. The UVa GUI can be seen in Fig. 1 and the INFN GUI can be seen in Fig. 2. The yellow columns are editable, and this is where the voltage settings, trip level, and ramp rate are changed. The HV can be turned on/off using the button on the left of each channel. The HV for INFN GEM J2 Top should always remain OFF, unless directed by GEM Experts or documentation changes. Currently INFN GEM module in J2 Top does not hold reasonable HV in stable conditions.
