9905-068 | Woodward | 2301A Load Sharing and Speed Control

Configured for prime mover load distribution and rotational velocity regulation, the Woodward 9905-068 (9905-068 Load Sharing and Speed Control) provides direct physical/electrical execution of speed sensing and actuator output control within governor systems.

Hardware Specifications

Actuator Loop Feedback Response

The 9905-068 2301A control module modulates the fuel system via a PID-based output stage designed to maintain engine speed setpoints. To ensure a stable actuator loop feedback response, the controller utilizes internal compensation, gain, and reset potentiometers, which allow for site-specific tuning to match the engine's mechanical time constants. If the prime mover fails to achieve rated no-load speed or exhibits hunting behavior during load sharing, these potentiometers must be adjusted to align the controller output with the actuator's physical response. The unit continuously monitors the load signal to facilitate precise synchronization and load sharing in multi-generator applications, requiring correct current transformer phasing for stable operation.

Frequently Asked Questions

Q: What is the procedure for verifying correct phase operation of the load signal?

A: With the prime mover in isochronous mode and not running, load the generator to near-full capacity and measure the voltage between the negative terminal 11 and positive terminal 13. If measurements indicate a phase error, rotate and record voltage/polarity across the three current transformers to verify correction.

Q: How can I optimize the control loop if the engine does not equalize for rated speed?

A: If speed equalization errors occur, verify the control operation and refine the actuator compensation, gain, and reset potentiometer settings. Ensure these adjustments are performed incrementally while observing the governor's response to step-load changes.

Field Installation Guidelines

1. Mounting: Secure the control module in an industrial enclosure using the specified mounting dimensions. Ensure the unit is protected from high-humidity and high-vibration environments, maintaining operation within the -40 to 85 deg C range.
2. Wiring: Use shielded cabling for speed sensor inputs and load signal connections to prevent electromagnetic interference. Terminate shields at the cabinet ground point to minimize ground loops that could introduce signal instability.
3. Power Connection: Connect a regulated 20-40 VDC power supply to the unit. Ensure the power source is capable of delivering consistent current, as fluctuations can degrade the precision of the speed sensing and control output.
4. Validation: Prior to initial startup, perform a cold-loop test to verify current transformer phasing and load signal polarities. Ensure the speed sensor impedance (100-300 Ohm) matches the MPU or proximity probe specifications before commissioning the prime mover into parallel operation.