Circuit breaker

A circuit breaker includes a tripping unit for interrupting an electrical circuit, and at least one current sensor for determining the electrical current flowing through the circuit breaker, connected to a control unit and configured such that the determined current is compared with current/period limit values. If a current/period limit value is exceeded, the tripping unit interrupts the electrical circuit. The current/period limit values include an adjustable first current limit value, present for a first period for an interruption; an adjustable second period, during which a second current limit value must be present to effect an interruption; and a range between the first current limit value and the second current limit value, the period decreasing with increasing current limit values in order to effect an interruption. The second current limit value can be adjusted at the circuit breaker.