ABB REF615K Relion 615 Series Feeder Protection and Control Relay

Configured for overcurrent, earth-fault, and voltage protection in medium-voltage power distribution systems, the ABB REF615K (REF615 Feeder Protection and Control Relay) provides direct physical/electrical execution. The withdrawable plug-in unit processes current and voltage transformer signals, drives circuit-breaker tripping circuits, and exchanges real-time data over substation Ethernet networks.

Hardware Specifications

Backplane Bus and Deterministic Substation Network Integration

The unit utilizes high-speed Ethernet physical layers to execute GOOSE messaging and sampled values under IEC 61850 Edition 1 and Edition 2 standards. High-availability Seamless Redundancy (HSR) and Parallel Redundancy Protocol (PRP) dual-port topologies eliminate single points of failure in deterministically networked switchgear environments. Time synchronization operates via IEEE 1588 V2 precision time protocol, maintaining exact sub-microsecond event timestamping across distributed protection panels. Substation automation controllers interface directly with the internal backplane architecture using PCM600 configuration toolsets for firmware flash updates and binary I/O mapping.

Frequently Asked Questions

Q: How does the withdrawable design impact live maintenance and module swapping?

A: The withdrawable plug-in unit incorporates automatic short-circuiting contacts for current transformer (CT) secondary circuits. However, field personnel must disconnect auxiliary supply voltage and open voltage transformer (VT) secondary fuses before extracting the internal unit to prevent arcing and unexpected trip signal outputs.

Q: What are the electrical constraints on binary inputs when routing long field cables?

A: The binary input threshold operates between 18 V DC and 176 V DC with a current drain of 2 mA to 18 mA. When field wiring runs exceed 100 meters, capacitive coupling may induce stray voltages above the 18 V DC threshold, requiring external damping resistors or isolated interposition relays to prevent false binary state triggers.

Field Installation Guidelines

Mount the unit vertically within a standard switchgear panel cutout. Maintain a minimum clear distance of 50 mm above and below the flush-mounted enclosure to ensure passive convection cooling through the heat sink vents.

Route low-voltage binary signal cables and analog CT/VT wiring through dedicated grounded metallic conduits separate from high-voltage primary conductors. Bond the main protective earth (PE) terminal located on the rear aluminum chassis directly to the substation earth bus using a green/yellow copper conductor with a minimum cross-sectional area of 4.0 mm2. Ensure the braid shields of all Ethernet RJ45 or fiber-optic cables ground at a single panel entry point to prevent ground loops. Maintain a minimum engagement of 5 full threads when torquing M4 chassis mounting screws to 1.2 N-m.