ABBDistributed busbar protection REB500 including line and transformer protection Product Guide

Distributed busbar protection REB500

including line and transformer protection

Main features • Low-impedance busbar protection

• Stub and T-zone protection

• High functional reliability due to two independent measurement criteria:

- stabilized differential current algorithm

- directional current comparison algorithm

• Phase-by-phase measurement

• Reduced CT performance requirements

• High through-fault stability even in case of 

CT saturation

• Full solid-state busbar replica

• No switching of CT circuits

• Only one hardware version for 

- 1 and 5 A rated currents

- all auxiliary supply voltages between 

48 V DC and 250 V DC

- nominal frequencies of 50, 60 and 

16.7 Hz

• Short tripping times independent of the 

plant’s size or configuration

• Centralized layout: Installation of hardware 

in one or several cubicles

• Distributed layout: Bay units distributed 

and, in the case of location close to the 

feeders, with short connections to CTs, isolators, circuit breakers, etc.

• Connections between bay units and central 

unit by fiber-optic cables

- maximum permissible length 1200 m 

- for distributed and centralized layout

• fiber-optic connections mean interferenceproof data transfer even close to HV power 

cables

• Replacement of existing busbar protection 

schemes can be accomplished without restrictions (centralized layout) in the case of 

substation extensions e.g. by a mixture of 

centralized and distributed layout

• Easily extensible

• User-friendly, PC-based human machine 

interface (HMI)

• Fully numerical signal processing

• Comprehensive self-supervision

• Binary logic and timer in the bay unit

• Integrated event recording

• Integrated disturbance recording for power 

system currents

• A minimum of spare parts needed due to 

standardization and a low number of varying units

• Communication facilities for substation 

monitoring and control systems via 

IEC 61850-8-1, IEC 60870-5-103 and LON

• IEC 62439 standard redundant station bus 

communication

• IEC 61850-9-2 LE process bus communication

• Cyber security to support

- User Access Management

- User Activity Logging

Options

• Breaker failure protection (also separately 

operable without busbar protection)

• End fault protection

• Definite time overcurrent protection

• Breaker pole discrepancy

• Current and voltage release criteria

• Disturbance recording for power system 

voltages

• Separate I0 measurement for impedancegrounded networks

• Communication with substation monitoring 

and control system (IEC 61850-8-1 /

IEC 60870-5-103 / LON)

• Internal user-friendly human machine interface with display

• Redundant power supply for central units 

and/or bay units

Additional 

main features

REB500sys combines the well-proven numerical busbar and breaker failure protection 

REB500 of ABB with Main 2 or back-up protection for line or transformer feeders. The 

Main 2 / Group 1 or back-up protection is 

based on the well-proven protection function 

library of ABB line and transformer protection 

for 50, 60 and 16.7 Hz.

Main 2 / back-up bay protection

• Definite and inverse time over- and undercurrent protection

• Directional overcurrent definite and inverse 

time protection

• Inverse time earth fault overcurrent protection

• Definite time over- and undervoltage protection

Distributed busbar protection REB500

including line and transformer protection

Page 3 

• Three-phase current and three-phase voltage plausibility

Main 2 / back-up bay protection: 

Line protection

• High-speed distance protection

• Directional sensitive earth fault protection 

for grounded systems against high resistive faults in solidly grounded networks

• Directional sensitive earth fault protection 

for ungrounded or compensated systems

• Autoreclosure for 

- single-pole / three-pole reclosure

- up to four reclosure sequences

• Synchrocheck with 

- measurement of amplitudes, phase 

angles and frequency of two voltage 

vectors

- checks for dead line, dead bus, dead 

line and bus

Group 1 / back-up bay protection: 

Transformer protection

• High-speed transformer differential protection for 2- and 3-winding and auto-transformers

• Thermal overload

• Peak value over- and undercurrent protection

• Peak value over- and undervoltage protection

• Overfluxing protection

• Rate of change frequency protection

• Frequency protection

• Independent T-Zone protection with transformer differential protection

• Power protection

Application REB500

The numerical busbar protection REB500 is 

designed for the high-speed, selective protection of MV, HV and EHV busbar installations 

at a nominal frequency of 50, 60 and 16.7 Hz.

The structure of both hardware and software 

is modular enabling the protection to be easily 

configured to suit the layout of the primary 

system.

The flexibility of the system enables all configurations of busbars from single busbars to 

quadruple busbars with transfer buses, ring 

busbars and 1½ breaker schemes to be protected.

In 1½ breaker schemes the busbars and the 

entire diameters, including Stub/T-Zone can