Contact pastille for a movable electrical contact of a circuit breaker, movable electrical contact with such a pastille and circuit breaker with such a contact

摘要

A contact pastille (3) destined to be fixed on a mobile contact (2) of a low voltage circuit breaker (1) designed to support peak short circuit currents of between 200 and 600 amperes per square millimetre of the pastille, is made of an alloy of conducting material with a base of silver (Ag) or copper (Cu), with a fraction of refractory particles such as tungsten carbide (WC), of tungsten (W) or of titanium nitride (TiN) and a fraction of carbon fibers. The overall content of carbon fibers is strictly less than 2% of the total mass of the contact pastille. The carbon fibers are crushed fibers with a medium length of less than 20 mu m. Independent claims are also included for the following: (A) a mobile contact for a circuit breaker incorporating this contact pastille; (B) a circuit breaker incorporating the mobile contact.