In FE probes, we need to avoid the focused, blowtorch beam landing on materials that may be damaged by it. For overnight periods or weekends or whatever long periods of no use, how do you leave the FE probe???
On the Cameca SXFive FE, there are apparently a couple of options. You do NOT want to leave the beam in the Faraday "cup" (annulus)...damage, contamination etc. Some people apparently leave it sitting on the metal holder (e.g. the 'reference' position). Also, you do not want to have the main valve between the chamber and gun (EP6) closed and blast it with the beam, as who knows what damage that ultimately might cause. Rather, my approach (following suggestions from Cameca personnel) is to set the "gun focusing coil" XHI value to 1000 (whereas the normal value is say 21). Then there is no beam down the column and the possibility of damage/contamination.
I don't know if Jeol FE probes have the same option in terms of gun focusing coils...