Description
The Woodward MFR 15 (8440-1771) is a compact, digital Multi-Function Protection Relay designed for generator protection and monitoring. It is part of Woodward’s specialized relay line, engineered to provide comprehensive electrical safety for small-to-medium power generation sets. This unit is widely used in applications where space is limited but high-reliability protection is required to monitor voltage, frequency, and phase-related disturbances in both isolated and grid-parallel systems.
Key Technical Specifications
- Primary Function: Digital protection relay for generator and mains monitoring.
- Protection Functions: Includes ANSI-compliant features such as Over/Under-voltage, Over/Under-frequency, Phase Sequence, and Vector Shift/ROCOF (Rate of Change of Frequency) for islanding detection.
- System Compatibility: Designed for stand-alone use or integration with Woodward’s broader power management controllers (such as the easYgen series).
- Metering: Provides real-time measurement of electrical values (True RMS voltage and frequency).
- Communication: Equipped with a serial RS-485 interface for configuration, data readout, and SCADA integration via Modbus protocol.
- Interface: Features a backlit LCD display and push-button navigation for local configuration and alarm acknowledgement.
- Safety/Standards: Meets industry-standard protection requirements for utility-interconnected generation (e.g., DIN V VDE 0126).
- Outputs: Multiple relay contacts for tripping the circuit breaker and signaling alarms.
- Diagnostics: Includes a trip log for historical fault analysis and front-panel status LEDs.
- Environment: Ruggedized for industrial switchgear cabinets; standard DIN-rail or panel-mount design.
Integration and Application
The MFR 15 is typically installed in the generator control panel. It continuously monitors the generator or mains bus voltage and frequency. Key operational roles include:
- Islanding Detection: Using ROCOF or Vector Shift to detect if the utility supply has failed, allowing the system to disconnect and protect personnel.
- Generator Safety: Protecting the generator from operating outside of safe frequency or voltage limits, which could damage connected equipment.
- Manual/Automated Control: Providing local visibility for plant operators to verify system health before closing the main breaker.
Related Woodward Protective & Control Components
To maintain a secure and reliable electrical distribution system, the MFR 15 is often deployed alongside:
- easYgen Series: Engine-generator controllers that manage starting, stopping, and load sharing.
- LS-5 Series: Circuit breaker control modules for synchronizing and breaker management.
- Potential Transformers (PTs): Required to step down high-bus voltages to the MFR 15 sensing levels.
- Current Transformers (CTs): Used if the specific relay variant includes overcurrent or reverse power protection.
- Test Switches: Industry-standard switches to isolate the relay for testing without shutting down the entire system.
- Mains Decoupling Relays: Standalone protection units for grid-tied applications.
- ToolKit Software: The engineering software used for advanced parameter configuration and firmware updates.
- 24VDC Power Supply: Regulated power for the MFR 15’s internal logic and display.
- Interposing Relays: Used to drive the high-current trip coils of large circuit breakers.
- SCADA/HMI Gateways: Devices to map Modbus data from the MFR 15 to a central plant monitoring station.
