The Woodward 8272-683 Digital Reference Unit (DRU) is a sophisticated electronic component designed to provide precise speed and load reference signals for prime mover control systems. Often paired with Woodward’s 2301A or 723 series governors, this unit acts as a digital-to-analog bridge, allowing operators to adjust engine or turbine speeds with high resolution and stability. Its rugged design ensures reliable operation in harsh industrial and marine environments, providing a stable setpoint that is immune to the drift typically associated with older potentiometer-based systems.
Product Specifications (Datasheet)
Dimensions: 125 mm x 100 mm x 85 mm Weight: 0.75 kg Country of Origin: USA Input Voltage: 18-32 VDC Output Signal: 0-10 VDC or 4-20 mA (Configurable) Resolution: 12-bit digital precision Operating Temperature: -40°C to +70°C Storage Temperature: -55°C to +105°C Enclosure Material: High-impact plastic or aluminum (depending on revision) Mounting: Standard DIN rail or bulkhead mount
Application Fields
The WOODWARD 8272-683 is essential for the following control architectures:
-
Power Generation: Precision frequency control for diesel and gas generator sets in paralleling applications.
-
Marine Propulsion: Managing throttle and speed references for main engines and thrusters on large vessels.
-
Steam Turbines: Providing accurate setpoint control for mechanical drive or generator drive turbine governors.
-
Compression Stations: Maintaining constant speed or pressure references for gas pipeline compressors.
-
Microgrid Systems: Interfacing legacy analog governors with modern digital load management controllers.
Product Instructions
-
Installation: Mount the unit in a vibration-protected area within the control cabinet. Ensure adequate clearance for wiring and cooling.
-
Electrical Connections: Connect the DC power source to the power terminals. Wire the output signal to the “Speed Reference” or “Remote Speed” input of the governor using shielded cable.
-
Signal Selection: Set the internal jumpers or DIP switches to select between voltage (0-10V) or current (4-20mA) output modes based on the governor’s requirements.
-
Calibration: Use the “Raise” and “Lower” contact inputs to sweep the output through its range. Adjust the “Span” and “Offset” trimpots if necessary to match the engine’s idle and rated speed setpoints.
-
Grounding: Ensure the unit and the cable shields are properly grounded to a single point to prevent electrical noise from causing speed fluctuations.
Q&A – Frequently Asked Questions
Q: Can this unit replace a manual speed potentiometer? A: Yes, it is designed to replace traditional potentiometers, offering a more stable, digital interface that can be controlled via remote pushbuttons or PLC contacts.
Q: What happens if the power to the 8272-683 is lost? A: The output signal will typically drop to zero or a pre-defined fail-safe level, causing the governor to return the engine to a minimum speed or shutdown state, depending on the governor’s configuration.
Q: Is this unit compatible with non-Woodward governors? A: Yes, because it outputs standard analog signals (0-10V or 4-20mA), it can be used with almost any electronic governor that accepts an external reference input.
Q: Does the unit remember the speed setting after a power cycle? A: Many versions of the 8272 series feature non-volatile memory that retains the last setpoint, but you should verify the specific firmware version for your application.
Similar Models Recommended
-
WOODWARD 8272-682
-
WOODWARD 8272-637
-
WOODWARD 9907-028
-
WOODWARD 8272-465
-
WOODWARD 2301A Speed Control Module
