When short circuit currents surpass equipment's short circuit rating, electromagnetic forces can seriously damage the equipment and initiate an arc fault. This test sequence shows what can happen when a short circuit rating downstream of the equipment exceeds its short circuit rating.

The images illustrate how current flowing in opposite directions through parallel bus bars can create a repulsive force between them, causing them to distort or even break away. When the bus bars contact other conductors or grounded components, an explosive arc fault is initiated.