The Woodward MRI4A0AB, also cataloged as the MRI4 3-Phase Feeder Protection Relay, operates as a dedicated hardware component for current monitoring, line protection, and trip logic execution within 3-phase power distribution networks.

Hardware Specifications

Actuator Loop Feedback Response and Thermal Heat Sink Dissipation

The Woodward MRI4A0AB utilizes digital signal conditioning to process 3-phase current signals and execute high-speed actuator loop feedback response to breaker trip solenoids during overcurrent or fault events. Incorporating passive thermal heat sink dissipation profiles within its compact 120 mm x 100 mm x 60 mm enclosure, the protection unit maintains tight threshold processing without thermal drift under heavy continuous sensing loads. The internal logic updates fault detection states with minimal latency to isolate downstream equipment and protect 3-phase feeder infrastructure.

Frequently Asked Questions

Q: What primary feeder protection functions are provided by the Woodward MRI4A0AB module?

A: The module is engineered specifically for 3-phase feeder protection, processing multi-phase current inputs to execute rapid trip logic for feeder circuit isolation.

Q: What are the physical chassis dimensions and overall unit weight of the MRI4A0AB?

A: The chassis measures 120 mm x 100 mm x 60 mm and weighs 1.2 kg.

Q: How does the unit interface with high-level power monitoring networks?

A: The relay incorporates standardized control interfaces to deliver real-time trip signals and operational status feedback directly to supervisory control systems.

Field Installation Guidelines

• Mount the module securely inside an IP54-rated or better control cabinet to shield the electronic circuitry from moisture and conductive dust.
• Route CT secondary wiring through dedicated high-integrity terminal blocks, ensuring current transformer lines are never open-circuited while energized.
• Use shielded, twisted-pair cabling for all trip command output signals and communications, grounding the cable shield at a single point to prevent ground loops.
• Maintain adequate physical spacing around the module perimeter to support natural air circulation across the passive thermal dissipating surfaces.