Method for interrupting electrical power between two conductors

A method for interrupting electrical power between two conductors is provided, including biasing an electrically conductive element into a conducting position between two contact regions of the conductors. The contact regions are preferably portions of arc runners coupled to the conductors. The conductors surround a magnetic core that generates an electromagnetic field due to current in the conductors. The conductive element is repelled to a non-conducting position by the electromagnetic field in response to an overcurrent condition in the conductors. A secondary response mechanism is moved in response to the overcurrent condition to maintain the conductive element in the non-conducting position. For more gradually occurring overcurrent conditions, the secondary response mechanism is attracted toward the core, displacing the conductive element to the non-conducting position. Arcs generated by movement of the conductive element are rapidly expanded under the influence of a magnetic field, thereby rapidly increasing the voltage opposing the fault current.