Patent ID: 7342762

Claim:
A circuit protection device comprising: a solid-state resettable switch; a first terminal in electrical communication with a first portion of the switch, the first terminal configured to be connected to a load; a second terminal in electrical communication with a second portion of the switch, the second terminal configured to be connected to a power source; and a controller configured to enable the switch to be opened if an accumulated energy meets or exceeds a preset I 2 t rating, the accumulated energy based on a current sensed from an electrical point between one of (i) the load and the switch or (ii) the power source and the switch, wherein the controller is configured to: (i) store a nominal current and read a sensed current for a time segment; (ii) add to the accumulated energy for the time segment if the sensed current is greater than the nominal current; and (iii) subtract from the accumulated energy for the time segment if the sensed current is less than the nominal current.