a handle, movable between an “ON” position and an “OFF” position;

a contact system, including at least one stationary contact and a movable contact;

an actuating device, operatively connected to the handle and the contact system such that, when the handle is actuated, the contact system is openable and closeable, wherein, in an event of a fault state, the handle is movable into a “TRIP” position arranged between the “ON” position and the “OFF” position via the actuating device; and

a safety lock, coupled to the handle and couplable to the actuating device such that, in the event of a locking state, the locking state being a fault state, in which the at least one stationary contact and the at least one movable contact of the contact system are not separated, the handle is prevented from moving from the “TRIP” position into the “OFF” position by the safety lock, via the coupling to the actuating device, wherein the actuating device includes a knee lever and the safety lock includes a locking bolt, wherein the knee lever is movably mounted, and wherein the locking bolt is mechanically operatively connected to the handle of the contact system and, in the event of a locking state, is operatively connected to the knee lever such that movement of the handle from the “TRIP” position to the “OFF” position is prevented, wherein, in the event of a locking state, the locking bolt makes contact with a first region of the knee lever, wherein, in the event of a trip state, the locking bolt makes contact with a second region of the knee lever.