Circuit breaker

A circuit breaker for protecting an electrical low-voltage circuit, the circuit breaker comprising:

• an electronic interruption unit;
• a mechanical break contact unit connected in series with said electronic interruption unit, said mechanical break contact unit having contacts and a handle for opening at least one of said contacts for avoiding a current flow or closing said at least one contact for allowing the current flow in the electrical low-voltage circuit;
• a controller connected to said mechanical break contact unit and said electronic interruption unit;
• and
• the circuit breaker is configured such that interruption of the current flow in the electrical low-voltage circuit is initiated by said mechanical break contact unit and/or said electronic interruption unit when current or current/time limit values are exceeded, the circuit breaker is configured such that said at least one contact of said mechanical break contact unit can only be closed by said handle if an approval signal for closing said at least one contact is present.