ABB REB615E_G Busbar Protection Relay Relion® 615 Series

1. Core Identity

Application: Busbar differential protection (87B) for substations up to 245 kV.

Hardware Platform: REB615E

Suffix "G": Standard hardware configuration (default I/O, measurement, comms).

Key Strength: Cost-effective stability for medium-sized substations.

2. Protection Functions

Function Technical Scope

High-Impedance Diff. 87B protection (stable up to 50 kA asym. fault current)

Check Zone Backup differential logic (2nd harmonic blocking)

CT Supervision Continuous monitoring for CT circuit failures

Breaker Failure (50BF) Backup tripping (programmable logic)

Zone Discrimination Configurable for up to 6 bus sections

3. Hardware Configuration ("G" Variant)

Module Specification

Analog Inputs Standard CTs (±0.5% accuracy)

Digital I/O 24 DI / 16 DO (expandable via XIO modules)

Communication 4× Ethernet ports (IEC 61850 GOOSE/MMS) + 2× optical (ST)

HMI 128×64 graphical LCD + keypad + multicolor LEDs

4. Technical Specifications

Parameter REB615E_G

Operating Speed <15 ms (internal fault)

CT Requirements Identical ratios across all bays

Stability Immune to CT saturation ≤ 20 cycles

Standards IEC 60255-1, IEEE C37.90, IEC 61000-4-4/4-5

Operating Temp -25°C to +55°C (standard)

5. Communication Protocols

IEC 61850 Ed.2: GOOSE class 1 (≤3 ms), MMS, Sampled Values

DNP3.0 over TCP/IP (LAN) / Serial (RS485)

IEC 60870-5-103 (legacy compatibility)

Modbus TCP/RTU

6. Applications

Distribution Substations (33–132 kV busbars)

Industrial Plants (critical process bus protection)

Retrofits: Direct replacement for ABB REB500 relays

Double-Bus Systems: Zone-selective logic for bus couplers/sectionalizers

7. Differentiation from REB615E_H

Feature REB615E_G REB615E_H

CT Accuracy ±0.5% (standard CTs) ±0.1% (High-precision HCTs)

Fault Immunity Stable up to 50 kA Stable up to 100 kA

Sampling Rate 32 samples/cycle 64 samples/cycle

Cost ~20% lower Premium tier