ABB REJ603 Self-Powered Numerical Feeder Protection

Overview

The ABB REJ603 is a compact, CT-powered feeder protection relay from the Relion® 605 series. It provides reliable short-circuit and earth-fault protection for RMUs and small transformers in secondary distribution networks. Its self-powered design makes it ideal for remote locations where auxiliary power is unavailable.

Technical Specifications

• Relay Type: Self-powered numerical feeder protection
• Protection Functions: 3-stage overcurrent, 2-stage earth-fault (IDMT + definite time)
• Power Supply: CT-powered (no auxiliary supply)
• Communication: None (standalone operation)
• Event Logging: Internal logs and fault recording
• Optional Inputs: Binary inputs (24–240 V AC/DC external supply)
• Mounting: Panel-mounted
• Applications: RMUs, secondary distribution, small transformers
• Relay Variants:
  • 1.5 – for special CTs
  • 3.0 – for conventional CTs
• Dimensions: 132.5 × 167 × 182.5 mm (W×H×D)
• Operating Temperature: −25°C to +55°C (continuous), −40°C to +85°C (short-term)
• Humidity: Up to 95% non-condensing