FN12-12D 12KV load break switch 630A 1000A 1. General FN12-12D/630-50 indoor AC high voltage load break switch, rated voltage is 12KV, rated frequency is 50Hz. It is a kind of three phases high voltage switch equipment. It can be used to breaking- closing load current, closed current, charge current for no-load transformer and cable, closing short-circuit current. The Load break switch which assembleds earthing switch can sustain short-circuit current. FN12-12DR/1000-31.5 indoor AC high voltage load break switch-fuse combination electrical appliance is a combinated indoor high voltage switch equipment which combinated by FKN12-12D load break switch and S?LAJ-12(XRNT?-12)high voltage limiting current fuse. This appliance can open any current up to short circuit current; Load break switch open working current, Fuse open short circuit current, combination open any current from working current to short circuit current, meantime Fuse makes the Load break switch opening through striking