The Woodward 9907-014 (Caterpillar part number 131-5453) is a 2301A series speed control designed to replace the discontinued older 2301 controls (Woodward 8272-689 / Caterpillar 4W-5790). This controller is widely used in speed control applications for generator sets, industrial engines, gas turbines, and other prime movers. It is available in both fixed speed and variable speed versions to meet different application requirements.
With the phase-out of the older 2301 controls, Woodward introduced the 9907-014 as a high-performance replacement solution. Compared to the older model, the 9907-014 features significant improvements in internal design, functional integration, and wiring configuration, resulting in enhanced system stability, response speed, and ease of use.
Background | Why Replacement Is Needed
For decades, the Woodward 2301 series has been an industry standard for engine speed control. However, as technology evolves and product lifecycles end, early models such as the Woodward 8272-689 (Caterpillar 4W-5790) are no longer in production. To ensure continued operation of existing equipment and reliable performance in new projects, Woodward launched the 2301A series, with the 9907-014 being the core replacement model.
This product not only retains the core control logic of the 2301 series but also introduces important improvements in terminal wiring layout, acceleration rate adjustment, and remote speed setting interfaces. Users can achieve a seamless upgrade without replacing the entire control system – only minor wiring changes are required.
Key Technical Differences | Old vs. New
1. Actuator Terminal Changes
On the older 2301 control (8272-689), the actuator connections were at terminals 5 (-) and 6 (+). On the 9907-014, the actuator connections have moved to terminals 9 (+) and 10 (-). This change requires reconnecting the actuator leads during replacement, but the actuator itself does not need to be replaced.
2. External Acceleration Rate Capacitor Removed – Now Internal
The older controller required an external acceleration rate capacitor to adjust ramp time. The 9907-014 integrates this function into the internal control circuit. Users can easily adjust the acceleration rate using the Ramp Time potentiometer on the control panel, simplifying hardware configuration and improving adjustment precision.
3. New SPM Synchronizer and Auxiliary Inputs
The 9907-014 provides richer input interfaces:
Terminals 15 and 16: Optional SPM synchronizer input, ideal for grid-paralleling applications requiring precise synchronization.
Terminals 15 (+) and 17 (-): Optional auxiliary input for external signals such as load sharing or power limiting.
4. External Droop Potentiometer Wiring Adjustment
On the older control, the droop potentiometer wiper connected to terminal 14, and the clockwise lead to terminal 13. On the 9907-014:
This change requires rewiring the droop potentiometer leads during replacement.
5. Speed Select Switch Wiring Adjustment
The contact for switching between rated speed and idle speed was on terminals 9 and 10 on the older control. On the 9907-014, it has moved to terminals 2 and 5. Switch closed = rated speed; switch open = idle speed.
Detailed Functional Features | Adapting to Various Control Needs
Fixed Speed Version
Suitable for applications requiring stable output speed, such as constant-speed generator sets. The 9907-014 fixed speed version supports:
Built-in acceleration rate adjustment via Ramp Time potentiometer for smooth starting
External droop adjustment for load sharing in parallel operation
SPM synchronizer input for grid paralleling
Auxiliary input for external signal intervention
Variable Speed Version
Suitable for applications requiring remote speed adjustment, such as industrial drives, pumps, and compressors. The 9907-014 variable speed version adds:
Remote rated speed setting via an external 10-turn, 1kΩ potentiometer
Idle/Rated speed switching via an external single-pole double-throw (SPDT) switch
Remote potentiometer terminals – terminal 11 (counterclockwise), terminal 12 (clockwise)
Wiring Guide | Key Points for Replacement
Fixed Speed Version Wiring Differences Summary
| Function | Old 2301 (8272-689) | New 2301A (9907-014) |
| Actuator (-) | Terminal 5 | Terminal 10 |
| Actuator (+) | Terminal 6 | Terminal 9 |
| Acceleration rate capacitor | External capacitor | Built-in Ramp Time pot |
| SPM synchronizer input | None | Terminals 15, 16 |
| Auxiliary input | None | Terminals 15 (+), 17 (-) |
| Droop pot wiper | Terminal 14 | Terminal 13 |
| Droop pot clockwise lead | Terminal 13 | Terminal 14 |
| Rated/Idle switch | Terminals 9, 10 | Terminals 2, 5 |
Variable Speed Version Additional Wiring Notes
In the variable speed version, in addition to the above differences:
Remote potentiometer assembly must be replaced with a single 10-turn, 1kΩ potentiometer.
Terminals 11 and 12 are used for remote rated speed setting.
Switch wiring: Rated/Idle switch connects to terminals 2 and 5.
Configuration and Tuning | Ensuring Stable System Operation
Remote Rated Speed Potentiometer Setup Procedure
Install a jumper between terminals 11 and 12.
Install an SPDT switch between terminals 2 and 5.
Adjust the rated speed potentiometer on the control to achieve 1980 rpm.
Open the switch between terminals 2 and 5. Adjust the low idle speed potentiometer on the control to the 700–1000 rpm range.
Shut down the engine, then remove the jumper from terminals 11 and 12.
Connect the remote rated potentiometer – rotate it to minimum resistance (<5Ω measured with an ohmmeter) before attaching leads to terminals 11 and 12.
Verify rated speed: Place the switch in the Rated position – engine should reach 1980 rpm. Adjust the remote rated potentiometer for 1960 rpm.
Verify idle speed: Place the switch in the Idle position – engine speed should be within 700–1000 rpm.
Safety and Precautions | Important Usage Guidelines
Overspeed Protection
Woodward emphasizes that all prime mover systems must be equipped with an independent overspeed shutdown device to prevent personal injury or equipment damage due to runaway or overspeed. The 9907-014 control does not replace an overspeed protection device.
Electrostatic Discharge (ESD) Awareness
The 9907-014 contains static-sensitive components. When installing, maintaining, or replacing the PCB, follow these ESD precautions:
Discharge body static by touching a grounded surface before handling the control.
Avoid wearing synthetic fiber clothing.
Do not touch conductors or components on the PCB.
Store and transport PCBs in antistatic protective bags.
Start-Up Preparation
Before starting the engine or turbine, operators must be prepared to make an emergency shutdown to protect against runaway or overspeed.
Personal Protective Equipment (PPE)
Recommended PPE includes:
Product Certifications and Compliance | Ensuring Legitimate Use
The Woodward 9907-014 is manufactured to strict quality standards. Any unauthorized modifications or use outside specified mechanical, electrical, or operating limits will:
Be considered "misuse" and/or "negligence"
Void product warranty coverage
Invalidate product certifications or listings
Before installation, operation, or maintenance, users must read all relevant manuals (e.g., Woodward manuals 82020, 82715) and follow all safety instructions.
Application Scenarios | Wide Industrial Suitability
1. Generator Set Control
The 9907-014 is ideal for generator set speed control, including:
2. Industrial Engine Drives
Suitable for constant-speed or variable-speed control of pumps, compressors, blowers, and other industrial equipment.
3. Marine Propulsion Systems
Can be used for speed control of main or auxiliary marine engines, supporting remote speed adjustment.
4. Turbomachinery Control
Suitable for speed regulation of small gas turbines and steam turbines.
Frequently Asked Questions (FAQ)
Q1: Can the 9907-014 directly replace an older 2301 control?
Yes, but wiring adjustments are required according to Application Note 51191. Actuator, droop potentiometer, and speed select switch terminals have changed positions.
Q2: Do I need to replace the actuator?
No. The 9907-014 is compatible with the same actuator types as the older 2301. Only the wiring needs to be reconnected to the new terminals (9+, 10-).
Q3: How do I adjust acceleration rate?
The older control used an external capacitor. The 9907-014 has a built-in Ramp Time potentiometer on the control panel for easy adjustment.
Q4: Does it support grid paralleling?
Yes. The 9907-014 provides SPM synchronizer input terminals (15, 16) for precise grid synchronization.
Q5: What type of potentiometer is needed for remote speed setting?
A 10-turn, 1kΩ potentiometer is recommended. Before connecting, ensure the resistance is at minimum (<5Ω).
