The REF 541, REF 543 and REF 545 feeder terminals are designed to be used for protection, control, measurement and supervision of medium voltage networks. They can be used with different kinds of switchgear including single busbar, double busbar and duplex systems.
The protection functions also support different types of networks such as isolated neutral networks, resonant-earthed networks and partially earthed networks. Application area also covers medium-sized three phase asynchronous motors as well as protection and control of shunt capacitor banks used for reactive power compensation. In addition to protection, measurement, control, condition monitoring and general functions, the feeder terminals are provided with a large amount of PLC functions allowing several automation and sequence logic functions needed for substation automation to be integrated into one unit.
The data communication properties include the following communication standards: SPA bus, LON bus, IEC 60870-5-103, IEC 61850 via SPA-ZC 400, Profibus DPV1 via SPA-ZC 302, DNP 3.0 and Modbus communication with higher level equipment. Further, the LON communication together with the PLC functions minimizes the need for hardwiring between the feeder terminals.