Data Stream Series CRD51XX measures true rms voltage, current, watts, VARs, energy, power factor, and frequency. Digital transducer is available in single-phase Model CRD5110; 3-phase, 3-wire Model CRD5150; and 3-phase, 4-wire Model CRD5170. Multiple data points are obtained from single device, and up to 35 devices can be connected on one RS485 bus with different addresses. Window openings accommodate current carrying wires up to 0.25 in. dia.