ABB, CT / VT INTERFACE CT / VT INTERFACE FOR DIRECT MONITORING - 4. Communication / Converters Quote now CT / VT interface for direct monitoring of 3/4 wires 110 VAC, 5A signals without mA transducers with serial interface to RTU560 (RS485).The following values are provided: 3 poles U, I, P, Q, S, active energy, reactive energy, cos phi, THD, 1 pole f