Cricuit-breakers must make and break all currents withing the scope of their ratings, from small inductive and capacitive load currents up to the short-circuit current, and this under all fault conditions in the power supply system such as earth faults, phase opposition and so on.
Further information you find in the booklet Vacuum Switching Technology and Components for Medium Voltage - Your guide on the right hand side.
Vacuum Switching Technology and Components for Medium Voltage - Your guide :