Low voltage circuit breaker

摘要

A low voltage circuit breaker with a current sensing unit having a magnetic circuit with three branches, the secondary winding being mounted on the intermediate branch and the primary winding being formed by a conductor selectively passing through one or two of the openings provided between the secondary winding and the outer branches. The circuit breaker comprises an instantaneous electromagnetic trip mechanism and a static long time and short time delay trip unit, the latter unit being governed by a signal attenuated by a rating selection device.