Patent ID: 7983014

Claim:
A disconnector for a plurality of electric wires, comprising: one or a plurality of current transformers that detect a current flowing through the electric wires, respectively; a rectifying part that rectifies the current outputted from the current transformers; a charging part that charges the current outputted from the rectifying part; a switching part that is connected in series to the electric wires and that disconnects the electric wires upon driving; a trigger part that drives the switching part when the charge stored in the changing part becomes a predetermined drive area; a zero phase current transformer that detects the vector sum of the currents flowing through the plurality of electric wires; a bypass part that can set a state in which the charge is not stored in the charging part; and a current vector sum detecting part that puts the bypass part in a state in which the charge is not stored in the charging part when the output of the zero phase current transformer is in a predetermined range, wherein the drive area is set larger than the charge that can be stored in the charging part by a lightning surge current.