Woodward 9907-205

Product Category
Magnetic Fuel Actuator / Solenoid Valve Driver / Electromagnetic Actuator for Engine Fuel Control

Key Functions

• Fuel Valve Positioning — Drives the fuel control rack to commanded position using solenoid electromagnetic force
• Fail-Safe Spring Return — Internal return spring drives actuator to full closed (fuel cut) position on loss of electrical signal
• PWM Signal Acceptance — Accepts 125 Hz or 250 Hz PWM signals from Woodward governors for proportional positioning
• Analog Signal Acceptance — Accepts 4–20 mA or 0–10 VDC signals from external controllers
• Position Feedback — Provides LVDT (Linear Variable Differential Transformer) output proportional to stroke position
• Overspeed Shutdown — Responds to ESD signal by cutting fuel within 50 ms
• Local Manual Override — Manual adjustment screw for commissioning and testing
• Reversible Wiring — Polarity-insensitive coil for simplified flexibility
• Built-in Diodes — Suppression diodes protect against voltage transients

Technical Specifications

Electrical Specifications

Position Feedback Specifications

Communication Interfaces

Protection Features

• Reverse Polarity Protection — Coil operates correctly regardless of supply polarity
• Overvoltage Protection — Internal TVS diode clamps at 36 VDC
• Transient Suppression — Built-in diode and RC snubber on coil
• ESD Response — Fuel cutoff within 50 ms of ESD contact closure
• Coil Thermal Protection — Internal thermistor triggers alarm at +130°C coil temperature
• Overstroke Protection — Mechanical stops limit travel to ±5% beyond rated stroke
• Short Circuit Protection — Current limited to 3 A maximum by controller

Control Modes

Material Composition

Structural Features

• Direct-mount design — Mounts directly to fuel rack via supplied bracket
• Deutsch DT06-6S connector — IP67 rated, 6-pin, keyed for correct orientation
• Integral 1.5 m shielded cable — Flying leads with stripped and tinned ends
• Manual adjustment screw — Accessible from front for zero-stroke calibration
• LVDT feedback port — Separate connector for clean signal routing
• ESD input terminal — Dry contact input on connector Pin 5
• Conformal-coated internal electronics — LVDT windings potted in epoxy
• Mechanical overstroke stops — Hardened steel pins limit shaft travel
• Vibration-damped mounting holes — Rubber grommets on mounting bracket

Working Principle

The 9907-205 operates on the principle of electromagnetic solenoid actuation with spring return. When electrical current flows through the solenoid coil, a magnetic field is generated that pulls the ferromagnetic armature (plunger) inward against the force of the return spring. The armature is mechanically linked to the actuator shaft, which moves linearly to open the fuel valve. The position of the armature is precisely measured by an internal LVDT (Linear Variable Differential Transformer). The LVDT core moves with the armature, changing the coupling between the primary and secondary windings, producing an AC voltage output proportional to shaft position. When electrical power is removed, the return spring forces the armature and shaft back to the fully closed position, cutting fuel supply. The actuator accepts a PWM signal from the Woodward governor. The governor varies the PWM duty cycle from 0% to 100%, which the actuator interprets as a position command from fully closed to fully open. The actuator’s internal driver circuit converts the PWM signal into a proportional average current through the coil, creating a proportional electromagnetic force that balances the spring force at the commanded position.

Advantages and Highlights

• Fail-Safe Design — Spring return ensures fuel cut on loss of all electrical signals
• High Force Output — 350 N pull force at 24 VDC, sufficient for large fuel valves
• Precise Positioning — 12-bit LVDT feedback, ±0.25% linearity, 0.0061 mm per step
• Dual Input Redundancy — Accepts both PWM (primary) and analog 4–20 mA (secondary) inputs
• Built-in Protection — Reverse polarity, overvoltage, transient suppression, thermal protection
• IP65 Rated — Suitable for harsh industrial, marine, and outdoor environments
• Long Service Life — MTBF exceeds 60,000 hours, no mechanical wear in solenoid
• Wide Temperature Range — -40°C to +85°C operation without derating
• Universal Compatibility — Works with all Woodward 5441, 5453, 5501, 9905, 9910 governors
• Easy Installation — Deutsch connector, integral cable, direct mount bracket

Applicable Industries

• Power Generation — Diesel and gas generator sets (standby, prime, continuous)
• Marine Propulsion — Main engine and auxiliary engine fuel control
• Oil and Gas — Compressor drivers, pump drivers, wellhead power units
• Mining — Diesel generator sets for underground and surface operations
• Rail — Locomotive engine governors
• Industrial — Any diesel/gas engine requiring solenoid fuel actuation
• Telecommunications — Cell tower and central office backup power
• Data Centers — Standby generator fuel control
• Military/Defense — Tactical and stationary power systems

Compatible Woodward Governors and Controllers

Model Series Cross-Reference

Certifications and Compliance

Part Number Breakdown

Installation Requirements

• Mount the actuator on the fuel rack using the supplied stainless steel 304 bracket
• Align the actuator shaft with the fuel rack lever arm using the manual adjustment screw
• Torque all mounting bolts to 8 Nm (70.8 in-lbs)
• Connect the Deutsch DT06-6S connector to the governor output — do not force the connector
• Route the integral cable away from high-current power cables (minimum 150 mm separation)
• Use shielded cable for any cable extensions (minimum 24 AWG)
• Ground the cable shield at the governor end only (single-point grounding)
• Verify the ESD input is wired to the emergency stop circuit
• Supply voltage must be 24 VDC regulated with less than 5% ripple
• Verify actuator stroke is 25 mm before connecting to the fuel rack
• Perform a no-load stroke calibration after initial installation
• Verify LVDT feedback signal is within 0.5 VAC to 4.5 VAC at full stroke

Usage Precautions

• Do not exceed the maximum supply voltage of 32 VDC — permanent damage to the coil will occur
• Do not apply voltage exceeding 32 VDC for more than 1 second — coil insulation will degrade
• Do not operate the unit in environments exceeding +85°C ambient temperature
• Do not block the ventilation openings on the actuator housing — overheating will occur
• Do not disassemble the actuator — no user-serviceable components are present
• Do not exceed the rated stroke of 25 mm — mechanical stops will engage and damage the shaft seal
• Do not apply side loads to the actuator shaft — this will bend the shaft and damage the LVDT
• Perform a functional test of the ESD circuit every 6 months
• Perform a stroke calibration check every 12 months
• Do not modify the firmware of the connected governor — this voids the actuator warranty
• Replace the FKM (Viton) O-rings if the IP65 seal is compromised
• Store the actuator in a dry environment with relative humidity below 85%
• Do not drop the actuator from a height exceeding 1 meter — internal LVDT windings will fracture
• The actuator contains a return spring under tension — do not disassemble without proper tools

Warranty

• Standard Warranty: 24 months from date of shipment
• Extended Warranty: Available up to 60 months (Woodward Protect program)
• Warranty Exclusions: Damage caused by overvoltage, physical impact, unauthorized disassembly, operation outside specified environmental limits, or use with incompatible governors

Document Reference Numbers