Woodward EM-80/EM-300 Electric Actuator Specification Guide

4. Environmental Ratings (Driver)

• Storage Temperature: –30 to +70 °C (–22 to +158 °F).

• Ambient Temperature Working Range: 0 to +55 °C (+32 to +131 °F).

• Ingress Protection: IP20 per IEC60529. This rating means the driver is protected against solid objects greater than 12.5mm (fingers) and water dripping vertically. This dictates that the driver must be installed in a clean, dry control cabinet, not on the engine itself.

• Pollution Degree: 2 (Non-conductive pollution; dry, non-conductive dust).

• Overvoltage Category: III (Equipment in fixed installations).

5. Cabling
Two distinct cables are required between the driver and the actuator:

• Power Supply Cable: A standard 3-phase cable including a protective earth conductor.

• Position Sensor Cable: This cable carries the resolver feedback. The maximum allowable length is 100 m (328 ft). This generous length allows the driver to be located remotely in a switchgear room while the actuator is mounted on the engine.

6. Filter (EMI)
An Electromagnetic Interference (EMI) filter can be added to the power supply to suppress emissions. However, the specifications explicitly state this filter is not recommended for ‘IT’ grounding schemes. IT (Isolated Terra) systems are common in some marine and industrial setups where the neutral is not earthed; using an EMI filter in these configurations can create a ground fault path or reduce safety.

7. Regulatory Compliance and Certifications
The EM-80/EM-300 system carries extensive certifications allowing for global deployment.

European Compliance:

• Low-Voltage Directive 2014/35/EU: Ensures safety from electrical hazards.

• EMC Directive 2014/30/EU: Ensures the system does not emit excessive electromagnetic interference and is immune to it.

Marine Type Approvals (Crucial for shipping):

• American Bureau of Shipping (ABS): Compliant with Part 1 – 2015 Steel Vessel Rules, specifically sections 1-1-4/7.7, 1-1-A3, and 1-1-A4. Also covers Mobile Offshore Drilling Units 2015.

• Bureau Veritas (BV): Compliant with Rules for Classification of Steelships (Jan 2013), Part C, Chapter 3, Section 6.

• Lloyd’s Register (LR): Type Approval System – Test Specification No. 1, 2002.

• Russian Maritime Register of Shipping (RMRS): Section 10, Part IV, RS Rules for Technical Supervision, Code of Nomenclature: 15100105.

• Specific Environment Ratings: The Driver is rated ENV2, and the Actuator is rated ENV4. These environment classifications typically denote the specific operating conditions (e.g., engine room vs. open deck) recognized by the classification society.

Key Features and Application Benefits

The Woodward EM-80/EM-300 series offers several distinct features that enhance usability and safety.

1. ISO 9409 Flange
The actuator output utilizes an industry-standard ISO 9409 flange. This standardized interface allows for easy mounting of levers and simplifies replacement. If an actuator fails, the ISO flange allows a technician to swap the unit without needing to machine custom adapters. Furthermore, the orientation of the output flange relative to the bracket base is identical for both EM-80 and EM-300 units. This interchangeability is a major advantage for inventory management; a shipyard or plant can keep one common interface design and swap between high-torque (EM-300) and high-speed (EM-80) units based on engine requirements.

2. Breakaway Stops
The actuators are equipped with breakaway stops designed to prevent the actuator from exceeding its maximum output travel range during setup. These stops are mechanical safety features intended to protect the internal gearbox during the installation and commissioning phase. They are not designed to withstand full operating torque during engine operation, which reinforces the need for proper external stop setting on the fuel rack.

3. Output Position Indicator
An output position indicator is standard equipment. This provides a visual, local indication of the actuator’s position, essential for technicians during manual testing or commissioning when the driver electronics may not be active or accessible.

4. Single Driver Compatibility
A single EM-driver is used for both EM-80 and EM-300. The software setup is the only variable. This reduces spare parts complexity. The driver is capable of auto-detecting or being configured for the specific inertia and torque characteristics of the attached motor/gearbox combination.

5. Monitoring and Diagnostics
Integrated monitoring allows the system to track most features of the actuator, including temperature, position error, and electrical faults. This diagnostic capability is vital for predictive maintenance, allowing operators to detect issues like winding shorts or resolver faults before they lead to catastrophic engine failure.

Conclusion

The Woodward EM-80/EM-300 MDS 5150A/LIT Actuator System provides a robust, all-electric solution for the control of large prime movers. By offering two distinct models, Woodward caters to the diverse needs of the industry: the EM-80 for applications demanding high-speed response and the EM-300 for those requiring high torque output. Both systems share a common architecture of a brushless AC motor, precision planetary gearbox, and a programmable digital driver, ensuring reliability and precision.