Comprehensive Protection Functionality

The device offers a full suite of protection functions, covering essential protections such as instantaneous overcurrent, time-delayed overcurrent, earth-fault, overload, and short-circuit protection. It also provides advanced protection features including directional overcurrent and residual overvoltage protection.
Protection schemes can be flexibly configured using software licensing options—higher-tier licenses enable additional functions such as differential protection, distance protection, and other advanced packages—allowing the device to meet the stringent requirements of different industrial and power system environments.

Accurate Monitoring and Intelligent Control

The system performs precise measurements of current, voltage, power, energy, and other key electrical parameters. It also supports monitoring of harmonics, circuit breaker operating cycles, trip coil health, and other equipment status indicators.
Comprehensive event recording enables operators to trace equipment behavior and operating sequences during abnormal or fault conditions. The device also provides circuit breaker control, automatic reclosing, and a clear multilingual LCD HMI, supporting both convenient local operation and seamless remote control via automation or SCADA systems.

Easy Adaptation and Maintenance

A modular design ensures convenient installation, expansion, and maintenance. The device maintains strong compatibility with the previous generation REF542, and a dedicated retrofit kit allows direct replacement in the original mounting position. Existing wiring harnesses require only minimal adjustments, significantly reducing installation workload and minimizing downtime.
The built-in self-diagnostic system continuously supervises both hardware and software status, while the binary I/O modules include watchdog contacts that issue alarms in the event of internal faults or power loss—enabling maintenance teams to quickly locate and resolve issues.

Typical Application Scenarios

Industrial Medium-Voltage Distribution

Ideal for medium-voltage networks in sectors such as petrochemical, chemical, mining, and large-scale manufacturing. It provides reliable protection for feeder lines, power transformers, and high-power motors, preventing production downtime caused by electrical faults.

Substation Automation

Fully compatible with ABB’s air-insulated (AIS) and gas-insulated (GIS) switchgear, and easily integrated into both ABB and third-party substation automation systems. It serves as a comprehensive protection and control unit for medium-voltage bays, supporting intelligent substation operation and maintenance.

Existing System Upgrade and Retrofit

Due to its high degree of compatibility with REF542, the device is widely used as a retrofit solution in legacy power distribution systems. It enhances the protection, control, and automation capabilities of old installations without requiring cabinet modifications or major rewiring, making it an ideal choice for power system modernization.