An electrical switching apparatus comprising: a plurality of first terminals including two input terminals structured to electrically connect to a direct current power source; a plurality of second terminals including two output terminals structured to electrically connect to a direct current load; a plurality of pairs of separable contacts; an operating mechanism configured to open and close said separable contacts; a trip actuator configured to cooperate with said operating mechanism to trip open said separable contacts; a plurality of conductors that electrically connect each pair of separable contacts between one of said first terminals and one of said second terminals; characterised by a transductor circuit including first and second current transformers (110,120), the transductor circuit being configured to sense a direct current component of a current flowing between at least one of the input terminals and at least one of the output terminals and to output an alternating current proportional to the direct current component; a current sensor configured to sense an alternating current component of the current flowing between at least one of the input terminals and at least one of the output terminals; an alternating current electronic trip circuit including an are fault detection circuit configured to detect an arc fault based on the sensed alternating current component, the alternating current electronic trip circuit being configured to control said trip actuator based on the alternating current output from the transductor circuit or the detected arc fault; and a power supply (500,500') structured to provide direct current power to the alternating current electronic trip circuit. a plurality of first terminals including two input terminals structured to electrically connect to a direct current power source; a plurality of second terminals including two output terminals structured to electrically connect to a direct current load; a plurality of pairs of separable contacts; an operating mechanism configured to open and close said separable contacts; a trip actuator configured to cooperate with said operating mechanism to trip open said separable contacts; a plurality of conductors that electrically connect each pair of separable contacts between one of said first terminals and one of said second terminals; characterised by a transductor circuit including first and second current transformers (110,120), the transductor circuit being configured to sense a direct current component of a current flowing between at least one of the input terminals and at least one of the output terminals and to output an alternating current proportional to the direct current component; a current sensor configured to sense an alternating current component of the current flowing between at least one of the input terminals and at least one of the output terminals; an alternating current electronic trip circuit including an are fault detection circuit configured to detect an arc fault based on the sensed alternating current component, the alternating current electronic trip circuit being configured to control said trip actuator based on the alternating current output from the transductor circuit or the detected arc fault; and a power supply (500,500') structured to provide direct current power to the alternating current electronic trip circuit.