Product Overview – Woodward 9905-204 DSM Synchronizer Module
When synchronizing generators to a common bus, precision and reliability are critical. The Woodward 9905-204 DSM Synchronizer Module delivers fast, accurate synchronization with digital speed matching and a small synchronizing window. This module ensures smooth parallel operation, reducing mechanical stress and electrical transients. Part of the 9900 series, the Woodward 9905-204 is designed for 115/230V-AC systems and operates from a 125 V DC power supply. Built for harsh environments, it supports temperatures from -35°C to 65°C, making it suitable for both indoor and outdoor installations.
Technical Specifications
| Parameter |
Value |
| Part Number |
9905-204 |
| Manufacturer |
Woodward |
| Series |
9900 |
| Product Type |
DSM Synchronizer Module 115/230V-AC |
| Operating Temperature |
-35 to 65°C |
| Power Supply Voltage |
125 V DC |
| Board Size |
33.0 cm high x 17.8 cm wide |
| Module Size |
8.25 cm high x 4.27 cm deep |
| Voltage Matching |
1% |
| Features |
Digital Speed Matching, Small Sync Window |
These specifications are directly from the manufacturer. For detailed wiring diagrams or additional parameters, contact the seller.
Industry Applications – Where the Woodward 9905-204 Excels
The Woodward 9905-204 is a preferred choice for generator synchronization in power plants, marine systems, and industrial cogeneration facilities. Its digital speed matching reduces synchronization time, while the 1% voltage matching minimizes reactive power fluctuations. For example, in a diesel generator set replacement project, upgrading to the Woodward 9905-204 can cut synchronization errors by eliminating analog drift. In combined heat and power (CHP) plants, this module supports parallel operation with multiple units, ensuring stable load sharing. The small sync window is especially beneficial when grid conditions are unstable.
Installation & Setup Guidance
Mount the Woodward 9905-204 securely on a DIN rail or panel using the provided slots. Ensure the ambient temperature remains within -35°C to 65°C. Connect the 125 V DC power supply to the designated terminals, observing correct polarity. For AC voltage sensing inputs (115/230V-AC), use appropriate fusing and verify phase rotation. After wiring, perform a dry-run test without generator excitation to confirm correct operation of the sync-check relays. Always refer to the product manual for detailed connection diagrams. Calibration is not required as the module self-configures upon power-up.
Maintenance & Reliability
Regular inspection of the Woodward 9905-204 is minimal. Annually check for dust accumulation on the ventilation slots and tighten any loose connections. The module’s solid-state design eliminates mechanical wear, contributing to long service life. The wide temperature tolerance reduces derating in hot climates. If replacing an older analog synchronizer with the Woodward 9905-204, expect reduced downtime and fewer nuisance trips. Routine functional tests every 12 months using a secondary injection test set can verify pickup and dropout timing.
Selection Guide & Purchasing Advice
Before purchasing a Woodward 9905-204, confirm your system voltage (115V or 230V AC) and DC supply rating (125 V DC). Check that the board height of 33.0 cm fits your enclosure. This module is a direct replacement for many Woodward 9900-series synchronizers. For fast shipping and genuine inventory, choose ubest101 as your supplier. We stock new and certified refurbished units with full traceability.