Digital guide
You are here:
WOODWARD 8444-1019F
Product Name
Digital steam turbine speed control and protection module, 505 series microprocessor governor.
Product Introduction
This module provides closed-loop speed regulation, load control, overspeed protection and emergency shutdown management for industrial steam turbines, single extraction/admission turbines, turboexpanders and small generator sets. It processes speed feedback, actuator commands and protective logic in one panel-mounted controller.
Detailed content
Technical Specifications
- Power supply: 18–32 VDC, 24 VDC nominal
- Speed control: PID based, isochronous and droop capable
- Overspeed protection: independent triple overspeed logic with test function
- Analog inputs: programmable current inputs for speed, pressure and auxiliary signals
- Discrete inputs: dry contact and programmable digital inputs
- Actuator outputs: analog current outputs for valve/actuator drive
- Relay outputs: alarm, trip, run and auxiliary relay contacts
- Display: two-line alphanumeric LED operator interface with control keypad
- Communication: RS-232, RS-422 and RS-485 for configuration and host integration
- Configuration software: 505View or equivalent Woodward toolset
Functional Features
- Automatic speed ramp, critical speed avoidance and load sharing
- Single or split-range actuator control for steam inlet and extraction valves
- Local/remote control priority and manual override
- Self-diagnostics for sensors, communication and trip relays
- Event logging, alarm history and on-site parameter adjustment
Application Scenarios
- Industrial steam turbines and cogeneration units
- Turboexpanders and process gas turbine auxiliaries
- Independent generator sets requiring grid synchronization
- Refinery, petrochemical and power plant turbine protection systems
Performance Parameters
- Operating temperature: -20°C to +60°C
- Storage temperature: -40°C to +85°C
- Enclosure rating: NEMA 4X or IP56 class industrial housing
- Control accuracy: stable speed holding under load disturbance when tuned per turbine dynamics
- Weight: approximately 4.1 kg
Material Composition
- Aluminum or coated steel enclosure with gasketed operator panel
- Industrial printed circuit boards with conformal coating options
- Sealed tactile keypad and LED display window
Structural Characteristics
- Panel-mounted controller with integrated operator keyboard
- Removable terminal blocks for power, analog and discrete wiring
- Isolated communication ports and grounded metal chassis
Working Principle
The module receives magnetic pickup or digital speed input, compares actual speed with setpoint, executes PID and protection algorithms, and outputs analog current to hydraulic or electric actuators. Overspeed, loss of signal and manual trip commands independently initiate shutdown logic.
Installation Requirements
- Mount in a control panel with adequate ventilation and vibration isolation
- Use separated trays for power, analog, discrete and communication cables
- Bond enclosure ground to turbine control system earth
- Verify actuator type, valve stroke and speed sensor calibration before commissioning
Usage Precautions
- Do not modify overspeed setpoints without authorized turbine protection calculation
- Confirm 24 VDC supply immunity to transients and ground loops
- Test overspeed trip and emergency stop functions during every planned outage
- Keep firmware, configuration backup and parameter records under version control
