Frequently Asked Questions about UR-81H
What is the function of the CT/VT modules found within the Multilin universal relays?
The CT/VT modules are simply one of many components that make up the Multilin GE UR Series universal relays. These universal relays can either come in a 19 inch horizontal mount, where each component is arranged in a vertical dimension across the relay, or a vertical mount relay that is three fourths of the size of the horizontal relay. In this mount, the components are arranged lying across one another vertically. In either case, some of the components in a universal relay are the CPU, the CT/VT module, the I/O Transducer, and the power supply. These universal relays also contain a digital input output component and an inter-relay communication capacity. Each of these components contributes to the designated purpose of the universal relay, weather the UR module is designed to be an I/O logic controller (C30), a breaker controller (C60), a unit that provides either multiple feeder protection or capacitor bank protection (F35 or C70), or a feeder protection relay with Hi-Z fault detection (F60). Regardless of the main function, the CT/VT module serves to provide the universal relay with up to 24 analog voltage transformer signals and analog current transformer signals in order to monitor AC power lines.