REF 541, REF 543 and REF 545 Feeder terminals

Features

• Feeder terminal for protection, control, measurement and supervision of medium voltage networks 

• New application areas for power quality measurement, protection, capacitor bank protection and control and motor protection 

• Voltage and current measurement via conventional measuring transformers or current and voltage sensors 

• Fixed man-machine interface including a large graphic display, or an external display module for flexible switchgear installation 

• Extended functionality including protection, control, measurement, communication, power quality and condition monitoring 

• Protection functions including e.g. nondirectional and directional overcurrent and earth-fault protection, residual voltage, overvoltage and undervoltage protection, thermal overload protection, CBFP and auto-reclosing 

• Control functions including local and remote control of switching objects, status indication of the switching objects and interlockings on bay and station level

• Measurement of phase currents, phase-tophase and phase-to-neutral voltages, residual current and voltage, frequency, power factor, active and reactive power and energy, etc. 

• Condition monitoring including circuitbreaker condition monitoring, trip circuit supervision and internal self-supervision of the feeder terminal 

• Additional functions including synchrocheck, frequency protection, capacitor bank protection and control, measurement of current and voltage harmonics 

• RTD/analogue module for temperature measurement, current/voltage measurement and mA-outputs 

• Communication over two communication interfaces: one for local communication with a PC and the other for remote communication via a substation communication system 

• Part of the ABB Substation Automation system

Application

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 and condition monitoring 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 SPA bus communication or LON bus communication with higher-level equipment. Further, the LON communication together with the PLC functions minimizes the need for hardwiring between the feeder terminals.

Design

The feeder terminals REF 541, REF 543 and REF 545 differ from each other regarding the number of digital inputs and outputs available. Please, refer to section “Ordering” for more details. These feeder terminals incorporate a wide range of feeder terminal functions: 

• Protection functions 

• Measurement functions 

• Power quality functions 

• Control functions 

• Condition monitoring functions 

• General functions 

• Communication functions 

• Standard functions The function blocks are documented on the CD-ROM “Technical Descriptions of Functions” (1MRS 750889-MCD).