Overview

The ABB REX010 is an Earth Fault Protection Unit designed to detect and isolate ground faults in electrical systems, preventing equipment damage and ensuring operational safety. It is widely used across distribution networks, substations, industrial electrical systems, and renewable energy platforms.

The REX010 supports both AC and DC control voltages, providing versatility for different system architectures. It features fast response times (<30 ms) and Modbus RTU communication for real-time fault reporting and remote diagnostics. This makes it ideal for applications requiring selective, high-speed earth fault protection.

For example, in a solar power station, the REX010 can detect insulation breakdowns and initiate protective actions before equipment damage occurs.

Technical Specifications

Typical Applications

• Medium-Voltage Distribution Networks: Detects ground faults and isolates affected feeders.

• Industrial Electrical Systems: Protects motors, transformers, and switchgear from insulation failures.

• Substation Automation: Integrates with SCADA systems for fault monitoring and control.

• Renewable Energy Systems: Ensures safe operation of solar and wind installations.

• Generator and Transformer Protection: Monitors neutral grounding and triggers alarms or trips during faults.

The REX010 is also commonly used in retrofit projects to replace legacy fault detection devices with modern, digital protection solutions.

FAQ

Q1: What voltage types does the REX010 support?
A1: It supports both AC (24–230 V) and DC (24–220 V) control voltages.

Q2: How fast does it respond to faults?
A2: It detects and reacts to earth faults in under 30 milliseconds.

Q3: Can it be monitored remotely?
A3: Yes, it supports Modbus RTU over RS-485 for remote diagnostics and control.

Q4: Is it suitable for harsh environments?
A4: Yes, it operates from –25°C to +55°C and meets IP20/IP10 protection standards.

Q5: What mounting options are available?
A5: It can be flush-mounted or surface-mounted depending on panel design.