WOODWARD 9907-838 Load Sharing Module with PWM Output

The WOODWARD 9907-838 is a load sharing module with pulse width modulated output, specifically engineered for use with Caterpillar engines equipped with a Caterpillar digital speed control with PWM input. This load sharing module allows use of Woodward power generation accessories and enables load sharing between Caterpillar digital speed control equipped engines and engines controlled with Woodward electronic controls. The module provides isochronous and droop load-sharing capability for engines equipped with Caterpillar digital controls in generator set applications.

Technical Specifications

The 9907-838 operates on 24 VDC power supply and features integrated surge protection for enhanced reliability in power generation environments. The module includes PWM output for direct compatibility with Caterpillar digital speed controls that accept PWM input. The input voltage range spans 18 to 32 VDC with reverse voltage protection up to minus 32 VDC and under-voltage and over-voltage protection up to 80 VDC. The module includes PT and CT three-phase inputs, with PT input requiring 100 to 240 VAC line-to-line voltage depending on configuration.

Load Sharing Capabilities

The 9907-838 is highly flexible in mounting options and is easy to configure for droop or isochronous applications. The load sharing module allows Woodward and non-Woodward engine load sharing, providing both isochronous and droop load-sharing capability. This flexibility makes the 9907-838 one of the few load sharing modules capable of accepting a Caterpillar type PWM input. The module integrates seamlessly with additional equipment in the control system including the Woodward SPM-A synchronizer, paralleling phase switch, import or export control, precision frequency control, automatic generator loading control, and automatic power transfer and loading control.

System Integration

The 9907-838 is designed for generator set applications where multiple engines must share load in parallel operation. The module allows precise load distribution among generators, ensuring power balance when multiple generators operate in parallel, preventing individual unit overload, and improving system stability and generation efficiency. The module is suitable for marine generator systems, land-based power generation facilities, and any multi-engine generator installation requiring coordinated load sharing between engines with different control system origins.

Protection and Reliability

The 9907-838 includes comprehensive surge protection to safeguard the module against voltage transients common in generator applications. The wide input voltage tolerance and reverse voltage protection ensure reliable operation even when power supply conditions are not ideal. The robust design is intended for installation in engine rooms and control cabinets where temperature variation and electrical noise are present. The module is manufactured by Woodward, a global leader in control solutions for industrial engines, turbines, and other prime movers, ensuring high reliability for critical power generation applications.

Applications

The WOODWARD 9907-838 is deployed in generator set applications requiring load sharing between multiple engines. Typical applications include marine vessel power systems where multiple generators operate in parallel for propulsion and ship service power, land-based diesel generator sets in industrial facilities requiring redundant or paralleled operation, and standby power systems where multiple generator sets must share load during utility outage. The module is also used in cogeneration plants, remote power stations, and any installation where Caterpillar digital speed control equipped engines must share load with Woodward-controlled engines or with other Caterpillar engines in parallel operation.