To solve such problems in an arrester which is provided at another place within the electric station independently of a structure such as a steel tower, in electric feeder line and electric power line drawn into an electric station via the steel tower, in order to protect a transforming device connected to such lines from an abnormal voltage such as cloud-to-ground discharge, etc., whereby a large lot is needed for the electric station which reduces layout flexibility of other devices, resulting in a high cost of the whole equipment.

An arrester body is included in a insulator to form a insulator type arrester which secures electric feeder line and power line to the steel tower with predetermined tension.