ABB REX521GHHGSH05G Feeder and Motor Protection and Control Relay

Description

Technical Specifications

• Product Type
  • Numerical Feeder and Motor Protection & Control Relay
• Application Voltage Level
  • Medium Voltage (MV): 6 kV – 36 kV
• Auxiliary Power Supply
  • AC: 110/120/220/240 V AC, ±15%, 50/60 Hz
  • DC: 110/125/220 V DC, ±20%
• Analog Inputs
  • Phase Current Inputs: 3 channels, configurable for 1 A or 5 A nominal CT secondary
  • Residual Current Input: 1 channel (5 A / 1 A)
  • Voltage Inputs: 3-phase voltage + 1 residual voltage input
  • Sensor Compatibility: Supports conventional current/voltage transformers and electronic sensors
• Binary Inputs/Outputs
  • Binary Inputs: 16 optically isolated, programmable digital inputs
  • Binary Outputs: 10 relay outputs (4 power outputs, 6 signal outputs)
• Communication Interfaces
  • Serial: RS-485 port
  • Local: Front USB port for configuration and service
  • Optional: Ethernet port for network communication
• Supported Communication Protocols
  • Modbus RTU/TCP
  • DNP3.0
  • SPA Bus
  • IEC 60870-5-103
  • Optional IEC 61850
• Physical Characteristics
  • Mounting: 19-inch rack-mountable, compact design
  • Display: Backlit graphical LCD with multi-language support
  • Control: Front-panel navigation buttons and LED status indicators
  • Protection Class: IP20 (front and rear)
• Environmental Ratings
  • Operating Temperature: -25 °C to +55 °C
  • Storage Temperature: -40 °C to +70 °C
  • Humidity: 5 – 95% RH (non-condensing)
  • EMC Compliance: IEC 60255-6, EN 55011
• Certifications
  • CE, UL, IEC 60255

Key Features

• Comprehensive Protection Functions
  • Overcurrent Protection: Three-stage, directional/non-directional phase and residual overcurrent protection with definite time (DT) and inverse definite minimum time (IDMT) characteristics.
  • Earth Fault Protection: Sensitive earth-fault (SEF) and directional earth-fault protection for high-impedance fault detection.
  • Voltage & Frequency Protection: Overvoltage, undervoltage, residual overvoltage, phase imbalance, phase reversal, and over/under frequency protection.
  • Motor-Specific Protection: Thermal overload, stall protection, start-up supervision, phase discontinuity, and fuse failure detection.
  • Advanced Functions: Circuit breaker failure protection (CBFP), trip circuit supervision, thermal overload for cables, and harmonic restraint for transformer inrush detection.
  • Auto-Reclose: Multi-shot automatic reclosing (up to 5 cycles) with configurable dead time and reclaim time.
• Precision Measurement & Monitoring
  • Real-time measurement of three-phase current/voltage, power, energy, power factor, and frequency with high accuracy.
  • Power quality monitoring: Total Harmonic Distortion (THD) analysis for current and voltage.
  • Event Recording: Stores over 1000 time-stamped events (Sequence of Events – SOE).
  • Disturbance Recorder: Captures fault data in COMTRADE format for post-fault analysis.
  • Circuit breaker monitoring: Tracks mechanical wear, operation count, and coil performance.
• Programmable Logic & Control
  • Embedded customizable logic control for automation, interlocking, and control schemes.
  • Local and remote circuit breaker control.
  • Configurable input/output logic for flexible system integration.
• Operational Flexibility & Security
  • Pre-defined standard configurations (B01/B02/M01/M02/H-series) for rapid deployment.
  • Multi-setting group functionality for adaptive operation under varying conditions.
  • Password-protected settings and role-based user authentication to prevent unauthorized access.
  • Continuous self-diagnostics and internal fault monitoring for high availability.
• Seamless System Integration
  • Wide protocol support ensures compatibility with SCADA, DCS, and substation automation systems.
  • Facilitates easy retrofitting into existing switchgear and control systems.
  • Supports remote configuration, monitoring, and firmware updates.

Application Scenarios

• Medium Voltage Utility Distribution
  • Primary protection for overhead lines and underground cables in radial and looped networks.
  • Incoming and outgoing feeder protection in distribution substations and ring main units (RMUs).
  • Suitable for isolated neutral, resonant earthed, solidly earthed, and resistively earthed systems.
• Industrial Power Systems
  • Protection and control for large medium-voltage motors (pumps, fans, compressors, mills).
  • Motor control center (MCC) protection in manufacturing, mining, and processing plants.
  • Critical load protection in petrochemical, water treatment, and cement factories.
• Substation Automation
  • Acts as a bay controller for feeder and motor bays.
  • Provides backup protection for power transformers and high-voltage lines.
  • Integrates into legacy and modern substation automation systems.
• Commercial & Infrastructure
  • MV distribution protection in data centers, airports, seaports, and large commercial buildings.
  • Ensures reliable power supply for critical infrastructure and continuous production processes.
• Grid Modernization
  • Deployed in smart distribution grids for fault location, isolation, and service restoration (FLISR).
  • Enables remote monitoring and control for efficient grid operation and maintenance.