Woodward 9907-029

Description

Product Category: Actuator Output Driver Module — PWM to High-Voltage DC

Application: Diesel and gas engine generator sets from 500 kW to 5000 kW with large fuel actuators requiring high-voltage drive

Function:
Receives a low-voltage PWM signal (0–5 VDC) from the Woodward 505 governor and amplifies it to a high-voltage PWM output (0–90 VDC) with sufficient current to drive large fuel solenoids and electronic actuators. Provides active current limiting, overvoltage protection, and actuator feedback monitoring.

Technical Specifications:

Material Composition:

Structural Features:

• Compact DIN-rail mountable module — fits in standard 35 mm TS 35 top-hat rail
• High-voltage output terminal block — accepts 10–18 AWG wire for actuator connection
• Low-voltage PWM input terminal — connects directly to Woodward 505 governor actuator output via dedicated cable
• Actuator feedback input terminal — accepts 4–20 mA or 0–10 VDC from actuator position sensor
• LED status indicators — Power (green), Output Active (green), Fault (red), Feedback Loss (amber)
• Built-in heat sink — aluminum finned heat sink provides passive cooling up to 4.5 A continuous
• Conformal-coated PCB — moisture and chemical resistance in harsh engine room environments
• Removable terminal blocks — allows field wiring without specialized tools
• DIN rail clip included — alternative to panel-mount bracket
• Labeling — laser-etched polyester film (permanent, UV-resistant)

Working Principle:

1. The Woodward 505 governor generates a low-voltage PWM signal (0–5 VDC, 500 Hz) proportional to the required fuel rack position.
2. The 9907-029 module receives this PWM signal at its input terminal.
3. An internal microcontroller decodes the PWM duty cycle and calculates the required output voltage (0–90 VDC).
4. The power MOSFETs switch the 24 VDC supply at 500 Hz to produce a high-voltage PWM output (0–90 VDC).
5. The output is filtered by an LC filter to produce a stable DC voltage proportional to the PWM duty cycle.
6. The filtered DC voltage drives the fuel actuator solenoid or EFA, moving the fuel rack to the commanded position.
7. The actuator position feedback (4–20 mA or 0–10 VDC) is monitored continuously by the module.
8. If feedback is lost (open circuit), out of range, or inconsistent with the command, the module triggers a fault and shuts down the output.
9. Overvoltage protection clamps the output at 95 VDC — if the output exceeds this, the module shuts down within 10 ms.
10. Overcurrent protection trips at 6 A — if the actuator draws excessive current (stuck solenoid), the module shuts down within 5 ms.
11. The module communicates fault status back to the governor via the feedback loss signal, enabling the governor to initiate a controlled shutdown sequence.

Key Advantages:

• 90 VDC high-voltage output — drives large fuel solenoids and EFAs that require high inrush current
• 5 A continuous current capacity (405 W) — sufficient for the largest actuators in 5000 kW gensets
• Active actuator feedback monitoring — detects stuck actuators, broken feedback wires, and position errors in < 10 ms
• Overvoltage clamp at 95 VDC — protects actuator from voltage spikes caused by inductive kickback
• Overcurrent trip at 6 A — protects wiring and actuator from short circuits
• 500 Hz PWM frequency — eliminates audible noise from fuel solenoid (audible noise starts at < 200 Hz)
• < 50 ms response time — fast actuator positioning for precise engine speed control
• Conformal-coated PCB — reliable operation in high-humidity, corrosive engine room environments
• DIN rail mountable — fits in standard instrumentation cabinets with high channel density
• UL Listed / CE / CSA / DNV / Lloyd’s — globally recognized certifications
• Direct compatibility with all Woodward 505 governors (8440 series) — no external wiring adapters required
• Built-in diagnostic feedback — governor receives real-time actuator health data
• No external power supply required — powered directly from the governor via 24 VDC

Applicable Industries:

Compatible Governor Models:

Compatible Actuators:

Installation Requirements:

• Mount on standard 35 mm TS 35 DIN rail in a clean, dry control room or cabinet
• Maintain minimum 50 mm (2 in) clearance above and below the module for heat dissipation
• Ensure ambient temperature remains between -20°C and +70°C (-4°F to +158°F)
• Connect 24 VDC power to terminals P+ and P− — supplied by the Woodward 505 governor via dedicated cable
• Connect PWM input signal from governor to terminals IN+ and IN− — use shielded twisted-pair cable, maximum 3 m (10 ft)
• Connect actuator output to terminals OUT+ and OUT− — use shielded cable, 10–18 AWG, maximum 15 m (50 ft)
• Connect actuator position feedback (4–20 mA or 0–10 VDC) to terminals FB+ and FB− — use shielded twisted-pair cable, maximum 30 m (100 ft)
• Connect earth ground wire to chassis ground terminal — use minimum 10 AWG copper wire
• Torque all terminal screws to 0.8 Nm (7.1 in-lbs) maximum
• Verify governor PWM output is configured for 0–5 VDC input on the 9907-029 module
• Verify actuator feedback type (4–20 mA or 0–10 VDC) matches the module configuration
• Perform no-load test after installation: verify output varies from 0 to 90 VDC as governor speed setpoint changes
• Perform load test: apply full load to genset and verify actuator moves smoothly without hesitation
• Configure fault response in governor — set to “trip on feedback loss” for SIL-rated applications

Usage Precautions:

• Do not exceed 90 VDC output — overvoltage destroys actuator windings and solenoid coils
• Do not exceed 5 A continuous current — overcurrent trips the module and damages the MOSFETs
• Do not connect 3-phase power — this module accepts 24 VDC power only from the governor
• Do not reverse actuator output polarity — incorrect OUT+/OUT− connection damages the MOSFETs
• Do not disconnect actuator feedback wire while running — loss of feedback triggers governor shutdown within 500 ms
• Do not ignore red fault LED — any fault requires immediate investigation before restart
• Do not use for actuators requiring > 90 VDC — this module’s maximum output is 90 VDC
• Do not use for actuators requiring > 5 A — this module’s maximum current is 5 A continuous
• Do not block ventilation openings — overheating causes thermal shutdown at 85°C ambient
• Do not operate outside -20°C to +70°C range — internal components degrade above 70°C
• Calibrate actuator feedback range — verify 4 mA = 0% rack position, 20 mA = 100% rack position
• Perform annual inspection — check terminal tightness, inspect for corrosion, verify LED indicators
• Replace module if fault LED is permanently red — internal component failure requires module replacement
• Do not mix 9907-029 with non-Woodward governors — PWM signal format is proprietary to Woodward 505 series
• Document all configuration changes in the genset commissioning log per NFPA 110
• Verify actuator inrush current < 5 A before connection — high inrush current trips overcurrent protection

Cross-Reference / Equivalent Part Numbers:

Warranty:
Woodward, Inc. provides a 24-month (2-year) limited warranty from date of shipment against defects in materials and workmanship under normal operating conditions. Warranty covers repair or replacement of defective modules at no charge. Warranty does not cover damage from misuse, overvoltage, incorrect installation, unauthorized modifications, or acts of nature. Extended warranty options (36-month and 60-month) are available through Woodward authorized distributors. Warranty registration is required within 30 days of installation via Woodward’s online portal.

Service Life:
10 to 15 years under normal operating conditions with annual inspection. Replace at each major genset overhaul or when the governor reaches end-of-support. The unit is designed for 100,000+ operating hours with proper maintenance. The internal MOSFETs have a rated life of 50,000+ switching cycles at full load. The CR2032 battery (if applicable for feedback memory) should be replaced every 10 years.

Documentation Reference:

• Woodward 505 Series Accessory Manual — Doc No. 82550-100 Rev. K
• Woodward 9907 Series Installation Guide — Doc No. 82550-101 Rev. J
• Woodward GSC (Governor Setup and Configuration) Software User Guide — Doc No. 82550-003 Rev. F
• NFPA 110: Standard for Emergency and Standby Power Systems (2022 Edition)
• ISO 8528-5: Reciprocating Internal Combustion Engine Driven Alternating Current Generating Sets
• IEC 61000-6-2: EMC — Generic Standards for Industrial Environments
• IEC 61000-6-4: EMC — Emission Standard for Industrial Environments
• Woodward Application Note AN-505-05: Actuator Driver Wiring and Configuration Guide
• Woodward Application Note AN-505-06: Feedback Monitoring and Fault Diagnosis Guide