Product Description

Overview

The ABB REB500BU (Part Number: 1KHL160006R0001H) is a decentralized Bay Unit designed for busbar protection in medium-, high-, and extra-high-voltage substations. It provides fast, reliable protection, control, and supervision of single busbars, suitable for high-impedance applications in utility and industrial power networks. This module also supports restricted earth-fault and residual earth-fault protection for generators, motors, transformers, and reactors.

The REB500BU serves as the local intelligence of a distributed busbar protection scheme, acquiring analog signals, monitoring breaker and isolator status, and transmitting data to a Central Unit (CU) for coordinated control.

Key Features

High-Speed Fault Detection

• Sub-cycle fault tripping for rapid response, typically within 15–20 ms, ensuring minimal disruption to primary equipment

• Low-impedance differential protection isolates only the faulted section of the busbar

Comprehensive Protection Functions

• Breaker Failure Protection (BFP): Monitors the tripping response of circuit breakers

• End-Fault Detection: Protects the line between CT and breaker

• Overcurrent and Overvoltage Backup: Provides independent back-up protection

• Disturbance Recording: Integrated memory for event waveform capture and analysis

Communication & Integration

• IEC 61850 Compliance: Full MMS and GOOSE support for digital substation integration

• High-Speed Data Exchange: Compatible with process bus architectures

• Redundant Networking: PRP (Parallel Redundancy Protocol) support ensures continuous communication even if a network path fails

Hardware & Environmental Specifications

• Multiple binary inputs for breaker/isolator status and fast-acting relay outputs for tripping

• Self-supervision of hardware and software health with immediate alarm generation

• Operating Temperature: –25°C to +55°C (standard) or up to +70°C in specific configurations

• Optimized for use with standard CTs, reducing system complexity and cost

Technical Specifications Table

Applications

• Substation busbar protection (MV, HV, EHV)

• Generator, transformer, motor, and reactor earth-fault monitoring

• Breaker failure detection and backup protection

• Digital substation integration with IEC 61850 networks

FAQ

Q: What role does the REB500BU play in a substation?
A: It acts as the local Bay Unit, monitoring currents, voltages, and breaker status, while supporting protection logic independently or in coordination with a Central Unit.

Q: Is it compatible with IEC 61850 systems?
A: Yes, it supports IEC 61850-8-1 with MMS and GOOSE protocols for seamless digital substation integration.

Q: What are the typical response times for fault detection?
A: Fault detection and tripping typically occur within 15–20 milliseconds.