A power breaker includes a switching contact arrangement having a current loop in order to allow a force dependent on the current to act on the contact members. For this purpose, sections, which are arranged parallel to one another and such that they are arched and concentric, are arranged on a stationary current conductor and on a contact lever. Depending on the position of a center of a resultant force, originating from the arched sections, in relation to a pivot bearing of the contact lever, a torque acts on the contact lever causing the switching contact arrangement to open or close. Using largely identical parts, power breakers which have a current-limiting or contact-force-increasing action can thus be produced.