Product Description
Woodward MRD1G5MA Motor Protection Relay
Product Overview
- The Woodward MRD1G5MA is a digital Motor Protection Relay designed for comprehensive protection and monitoring of electric motors in industrial applications, such as power generation, manufacturing, marine systems, and process industries. Part of Woodward’s MRD series, this microprocessor-based relay safeguards motors against electrical faults, including overcurrent, overload, phase imbalance, and ground faults. The "G5MA" designation indicates a 5 A nominal current input with specific firmware or hardware configurations for enhanced motor protection features. The MRD1G5MA offers precise protection settings, fault diagnostics, and communication capabilities for integration into modern control systems. Compared to Woodward’s genset controllers (e.g., EasyGen-3500-5, 8440-2087), excitation systems (e.g., DECS-100-B15), or current relays (e.g., IRI1-I5E05D), the MRD1G5MA is tailored specifically for motor protection, not engine or generator control. It is distinct from Woodward’s electronic governors (e.g., DYN1-10784-003-0-12), actuators (e.g., 8408-921), and other modules (e.g., 5466-1510 CPU).
Technical Specifications
- The MRD1G5MA has the following specifications based on industry sources and Woodward documentation:
| Specification | Details |
|---|---|
| Model/Part Number | MRD1G5MA |
| Manufacturer | Woodward |
| Description | Digital Motor Protection Relay |
| Series | MRD |
| Function | Protects and monitors electric motors against electrical faults |
| Processor | Microprocessor-based (specific architecture not publicly detailed) |
| Memory | Flash: 4–8 MB (for firmware and configuration) RAM: 2–4 MB (for runtime data) |
| Display | LED indicators; optional external HMI or PC interface for configuration |
| Inputs | 3-phase current inputs (5 A nominal, 0.1–40 A range) 1 ground fault current input (5 A or sensitive ground fault detection) 2 analog inputs (optional, 4–20 mA or RTD for temperature) 4 discrete inputs (24 VDC) |
| Outputs | 4 relay outputs (dry contact, up to 250 VAC/5 A) 1 analog output (optional, 4–20 mA) |
| Communication Interfaces | 1 serial port (RS-485, Modbus RTU) CANbus (optional, for integration with control systems) |
| Protection Functions | Overcurrent (instantaneous and time-delayed), overload (thermal model), phase imbalance, ground fault, undercurrent, locked rotor, over/under voltage (optional) |
| Trip Accuracy | ±5% of set value (current), ±2% (thermal model) |
| Protection Settings | Configurable trip thresholds, time delays, thermal curves, and fault detection parameters |
| Redundancy | Non-redundant |
| Diagnostics | Fault detection, event logging (up to 200 events), motor running hours, status LEDs |
| Compatibility | Compatible with Woodward control systems (e.g., EasyGen-3200-5, 8440-2050), SCADA systems, and third-party devices via Modbus; suitable for low- and medium-voltage motors |
| Power Supply | 24–250 V AC/DC (universal input) |
| Power Consumption | Approx. 5–10 W |
| Environmental Specifications | Operating Temperature: -25°C to +70°C (-13°F to +158°F) Storage Temperature: -40°C to +85°C (-40°F to +185°F) Relative Humidity: 5% to 95% non-condensing Vibration: IEC 60068-2-6 compliant Shock: IEC 60068-2-27 compliant |
| Enclosure | IP40 (with proper enclosure); IP20 (rear) |
| Dimensions | Approx. 110 mm (H) x 120 mm (W) x 100 mm (D) |
| Weight | Approx. 0.5–1 kg |
| Mounting | Panel-mounted or DIN rail |
| Certifications | CE, UL, CSA, marine certifications (e.g., DNV, ABS, configuration-dependent) |