9907-173 | Woodward Module Load Sharing 120 Volt

Product Overview

The Woodward 9907-173 is a Load Sharing Module (LSM Series) designed for paralleling generator sets and managing load distribution across multiple engines or generators. It ensures balanced real and reactive power sharing in synchronized applications, supporting both isochronous and droop load sharing modes. The 9907-173 is compatible with both Woodward and non-Woodward speed controls, making it a versatile solution for industrial and power generation settings.

Key Technical Specifications

• Product Type: Load Sharing Module (LSM Series)
• Series: Woodward 9907 Series
• Function: Isochronous and droop load sharing
• Power Supply: 115/230 VAC (95–130 or 190–260 VAC), 50–400 Hz
• Power Consumption: Approx. 5 W
• CT Inputs: 3-phase, 3–7 Arms at full load
• PT Inputs: 3-phase, 100–240 VAC line-to-line
• Analog Output: ±3 VDC
• Output Type (Alternative): PWM/GenDec
• Droop Range: 0–10% speed reduction
• Humidity: Up to 95% RH (non-condensing)
• Shock Resistance: 40 G
• Overvoltage Category: Category III
• Environmental Rating: IP54
• Operating Temperature: -40°C to +60°C
• Dimensions: 273.6 mm × 59.2 mm × 214.1 mm
• Weight: 2.5 kg (2500 g)
• Mounting: Panel-mounted
• Origin: USA

Key Features

• Dual Load Sharing Modes: Isochronous (constant frequency) and droop (proportional sharing)
• Wide Compatibility: Works with both Woodward and non-Woodward speed controls
• 3-Phase Sensing: CT and PT inputs for accurate power measurement
• Adjustable Droop: 0–10% speed reduction range for fine-tuning
• Robust Construction: 40G shock resistance and IP54 environmental rating
• Reverse Voltage Protection: Up to -32 VDC
• Overvoltage/Undervoltage Protection: Up to 80 VDC

Applications

• Industrial power plant generator paralleling
• Marine power generation systems
• Cogeneration facilities
• Backup power systems
• Utility grid-tie applications
• Caterpillar engine load sharing

Installation Guide

1. Mount on panel in generator control cabinet
2. Connect 115/230 VAC power supply
3. Wire 3-phase CT inputs (3–7 Arms at full load)
4. Connect 3-phase PT inputs (100–240 VAC line-to-line)
5. Wire ±3 VDC analog output to governor speed bias input
6. Configure isochronous or droop mode per application
7. Test load sharing performance with varying loads

FAQ

Q: What is the difference between isochronous and droop load sharing?
A: Isochronous maintains constant frequency regardless of load; droop allows slight frequency decrease with increasing load for stable parallel operation.

Q: Can it work with non-Woodward governors?
A: Yes, the 9907-173 is compatible with both Woodward and non-Woodward speed controls.

Q: What is the analog output signal?
A: ±3 VDC speed bias signal to the governor.

Q: How many generators can share load?
A: Typically up to 16 generators can be paralleled on a single load sharing bus.

Q: What is the droop adjustment range?
A: 0–10% speed reduction, adjustable for optimal load sharing characteristics.

Model Selection Tips

• 9907-173 = Load Sharing Module (LSM Series) for parallel generator operation
• Verify governor accepts ±3 VDC speed bias input
• Confirm CT ratio (3–7 Arms) matches your instrument transformers
• For automatic synchronization + load control, consider 9907-005 (Master Synchronizer)
• For diesel engine-specific applications, verify Caterpillar compatibility if applicable