Autoexpansion circuit breaker with insulating gas

摘要

The electric circuit breaker comprises a gas expansion cut-off chamber (34) enclosing separable arc contacts and an electromagnetic coil (122) for causing rotation of the arc. An insulating support arm (62) is fixed to the end of the cartridge (43) and comprises a base (108) fixed on a first internal step (110) of the cartridge (43) by screws (111). A thermal screen (114) is positioned on the base (108) to serve as a flame barrier. The excitation of the coil (122) is effected through a part of the magnetic circuit (138).