3A300

Each 3A300 station comprises an intertrip send input interfaced to the local protection trip contact, an intertrip receive output contact interfaced to the local breaker, an isolated DC intertrip voltage for the pilot wire, pilot wire supervision, a trip voltage supply input for trip circuit supervision, self-supervision circuitry with alarm, and a control panel for setting and status display. Intertripping applies a 2-second DC signal onto the pilot; any station can initiate it and all others respond. AC filtering provides immunity to induced AC voltages, and 5kV or 15kV pilot wire isolation is provided via an encapsulated isolating transformer.