Description
Product Datasheet & Technical Parameters
- Brand: WOODWARD
- Model: 9905-287
- Series: DSLC (Digital Synchronizer and Load Control) Series
- Product Name: Digital Synchronizer and Load Control Unit
- Manufacturing Origin: United States
- Physical Condition: Brand New / Factory Sealed
- Dimensions: 461 mm \times 265 mm \times 59 mm (approx. 18.15 \times 10.43 \times 2.32 in)
- Weight: Approx. 6 lbs 14 oz (3.12 kg)
- Country of Origin: USA
- Power / Input Rating: 8 VDC to 32 VDC Power Supply Range, Frequency Input 45 to 66 Hz, Three-phase Generator Bus and Single-phase Parallel Bus
Product Overview & Introduction
The WOODWARD 9905-287 is an earlier-generation microprocessor-based Digital Synchronizer and Load Control (DSLC) unit designed for AC, three-phase generator systems. It provides precise synchronization, frequency matching, and automated active power load sharing across parallel generator applications. Built to operate reliably in demanding environments, this robust control unit integrates core power management functions to maintain stability and safety during parallel switching operations.
Operational Specifications & Guidelines
Prior to installation or handling, ensure that all electrical power sources are completely de-energized and discharge any static electricity from your body to ground by touching a grounded metal object, as the unit is static-sensitive. Mount the 9905-287 module securely inside a protective sheet metal panel control enclosure, maintaining an operating temperature range between -40–70^\circC and relative humidity levels up to 95\%. Connect the 8–32 VDC power supply, frequency inputs (45–66 Hz), three-phase generator bus lines, and single-phase parallel bus lines strictly in accordance with the manufacturer’s wiring schematics. Verify all terminal connections and ensure system grounding integrity before restoring power.
Startup & Shutdown Sequencing
To prevent breaker tripping, out-of-phase synchronization, or system instability, operators must strictly follow the defined startup and shutdown procedures.
- Startup Sequence:
- Verify all external wiring, potential inputs, control power connections, and safety interlocks are securely fastened.
- Energize the DC control power supply (8–32 VDC) to the WOODWARD 9905-287 module and wait for the internal diagnostic self-test to complete successfully.
- Start the prime mover and allow it to reach rated nominal speed and thermal stability under governor control.
- Enable the synchronizer module to monitor bus and generator frequency and phase parameters.
- Engage the automatic synchronizing and load-sharing mode, allowing the unit to execute precise speed adjustments and issue the close command to the circuit breaker precisely at the synchronous point.
- Shutdown Sequence:
- Gradually transfer active electrical load away from the generator set back to the main utility grid or companion units until minimum baseline load is achieved.
- Open the main generator circuit breaker manually or via system command to isolate the unit electrically from the busbar.
- Initiate the prime mover cool-down cycle at idle speed for the required duration.
- Issue the stop command to shut down the engine or turbine completely.
- De-energize the auxiliary control power to the module only after the prime mover has come to a complete standstill.
Frequently Asked Questions (Q&A)
- Q1: What are the power supply and frequency input limits for the WOODWARD 9905-287?
- A1: The unit operates on a DC power source ranging from 8 VDC to a maximum threshold of 32 VDC, and supports frequency inputs between 45 and 66 Hz.
- Q2: What phase configurations does this specific DSLC model support?
- A2: The module is designed to handle a three-phase generator bus alongside a single-phase parallel bus configuration.
- Q3: Is the WOODWARD 9905-287 sensitive to electrostatic discharge?
- A3: Yes, the unit is static-sensitive and ships in protective packaging; technicians must discharge static electricity to a grounded metal object before performing maintenance or installation.
