Description
The Woodward 9907-175 is a dedicated Load Sharing and Speed Control Module designed for the synchronization and load management of multiple generator sets. It is a critical component in paralleling applications, ensuring that engines connected to a common bus share the electrical load proportionally. This module is widely used in power generation systems where reliability and precise frequency control are essential for grid stability.
Technical Parameters
- Model: 9907-175
- Component Type: Load Sharing & Speed Control Module
- Input Power: 24 VDC (Nominal)
- Control Output: Proportional speed signal to the engine governor
- Dimensions: 150 mm x 120 mm x 90 mm
- Weight: 1.1 kg
- Origin: USA
Application Areas
- Prime power generation for commercial/industrial facilities
- Emergency standby power systems
- Multi-generator load shedding and synchronization
- Marine shipboard power management
Product Usage Instructions
- Mounting: Install the module in an electrical cabinet designed for vibration dampening to protect the internal electronic components.
- Wiring: Connect the generator’s current transformer (CT) signals and the potential transformer (PT) voltage references according to the schematic; ensure that CT polarities are correct to avoid inverse load sharing.
- Configuration: Utilize the onboard potentiometers to adjust gains, droop characteristics, and load-sharing bias to match the engine/governor combination.
- Synchronization: Before putting the system online, verify that the load sharing bias signal correctly adjusts the engine speed in response to changes in the total system load.
Product Description
The 9907-175 functions by monitoring the real power (kW) output of the generator and comparing it to the load-sharing bus. It provides a corrective signal to the engine governor, automatically adjusting engine speed to balance the load with other generators on the same bus. This process ensures that no single generator is over-strained and that the total bus frequency remains within strict tolerances regardless of load fluctuations.
Protection & Environmental Parameters
- IP Rating: Designed for housing within NEMA-rated industrial enclosures.
- Corrosion Resistance: Conformal coating on all internal circuitry to protect against harsh industrial environments.
- Operating Temperature: 0°C to +70°C.
- Storage Temperature: -40°C to +85°C.
- Humidity: 5% to 95% relative humidity, non-condensing.
Mechanical & EMC Standards
- Vibration Resistance: Tested for high-stress environments characteristic of engine rooms and power plants.
- Shock Resistance: Built to withstand industrial mechanical impact.
- EMC Compliance: Designed for high immunity to electromagnetic interference (EMI) typical in high-voltage power generation environments, preventing signal errors in the control loop.
Frequently Asked Questions
- How does the 9907-175 communicate with other units? It uses a dedicated, low-impedance analog load-sharing bus line to communicate power-level requirements between parallel generators.
- Can this be used with non-Woodward governors? It is designed to work with most standard isochronous governors, but compatibility with the specific governor’s speed-trim input must be verified.
- What is the most frequent cause of load-sharing imbalance? Imbalance is most commonly caused by incorrect CT scaling, polarity reversal, or improper gain settings on the module.
- Is this a digital or analog module? The 9907-175 is an analog-based control module, offering fast, real-time response times suitable for critical power synchronization.
