Method and circuit for detecting an arc fault

A method of detecting a circuit fault, comprising: sensing a power characteristic at a switch output 34; at a controller module, receiving the power characteristic and determining a presence of a circuit fault; generating a first control signal to open the switch 28; determining, in the controller module, whether the fault is still occurring and if so, generating a second signal to close an active pull down switch 30. A circuit comprising: a switch 28 operable to supply power from a power source to an electrical load 20; a sensor sensing an electrical characteristic; a controller module 60 communicatively connected with the switch and the sensor, and controlling the supply power, receiving the electrical characteristic and ceasing the supply power to the electrical load by switch 28 in response to determining the electrical characteristic indicates a fault; a comparator module 68 configured to receive the electrical characteristic from the sensor and, upon failure of the controller module, to cease supplying of power to the electrical load by the switch, operably control an active pull down switch 30 to redirect the supplying power to an electrical ground.