ABB REF 541 Feeder terminals

ABB REF 541 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-to-phase 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.

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

Protection functions

Protection is one of the most important functions of the REF 54_ feeder terminal. The  protection function blocks are independent of  each other and have their own setting groups,  data recording, etc.

Either Rogowski coils or conventional current transformers can be used for protection  functions based on current measurement.  Correspondingly, voltage dividers or voltage  transformers are used for protection functions  based on voltage measurement.

For further information about functionality levels and the protection functions included  in them, refer to the table “Functionality levels, protection functions” in section  “Ordering”.