The invention relates to a lightning conductor which carries the thermal excitation type abscission implement, belongs to the arrester and its abscission implement domain. It is composed of the arrester, the thermal exciter and abscission implement. The inferior extremity of the arrester connects with the superior extremity of the thermal exciter; the inferior extremity of thermal exciter connects with the superior extremity of the abscission implement. The arrester connects with the out-circled electric heating wire of normally open contact and the bimetallic strip in the thermal exciter; the normally open contact connects with the abscission implement, the inferior extremity of the abscission implement and the inferior extremity of the electric heating wire both connect with the earth line. The thermal exciter is composed of outer covering, superior connecting fitting, inferior connecting fitting, earth line connection bullion, strip conductor, the normally open contact, bimetallic strip and out-circled electric heating wire. The normally open contact, bimetallic strip and out-circled electric heating wire all install in the thermal excitation crustaceous atrium. When the electrical network has happened the thunder stroke voltage, the thunder current through the electric heating wire joins to the ground, no longer induces the abscission implement detonation. Once the arrester had short circuit damaged, the short-circuit current caused the heating wire to detonate the abscission implement, prevented the electrical network high pressure earth accident.