A circuit interrupter includes a sensor structured to output a sensor signal, a control unit structured to receive an external control signal, the control unit including: a communication interface structured to receive the external control signal, and a waveform generator structured to generate a waveform equivalent to the sensor signal in response to the external control, and a signal processing circuit structured to receive and process the sensor signal or the generated waveform and to output the processed sensor signal or generated waveform to the control unit.