Woodward 9905-376 24VDC Digital Governor New Original

Product Overview

The Woodward 9905-376 serves as a high-precision digital governor designed specifically for single-valve steam turbines. As part of the globally recognized 505/505E series, this controller manages speed regulation, extraction/admission sequencing, and load sharing with millisecond accuracy. We supply this unit as 100% brand new and original, ensuring critical infrastructure remains operational without the risks associated with used or refurbished hardware.

Technical Specifications

Engineering Advantages

Integrated Operator Control Panel (OCP)

The 9905-376 eliminates the need for external HMI hardware in basic setups. The front-mounted 24-character LCD provides real-time feedback on turbine speed, load, and valve position. Operators use the integrated keypad to adjust setpoints or configure PID parameters directly at the machine level, streamlining commissioning and localized monitoring.

Precision Extraction/Admission Management

Unlike standard governors, this 505E-tier module handles split-range actuator configurations and single extraction systems. It automatically calculates the complex relationships between inlet flow, extraction flow, and electrical load to maintain constant header pressure and grid frequency simultaneously.

Robust Communication and Data Logging

The module utilizes Modbus RTU protocols via RS-232 or RS-422 ports to bridge the gap between field mechanicals and the central DCS. It transmits critical diagnostic data and alarm logs, allowing plant engineers to predict maintenance needs and analyze turbine trips with high-resolution timestamps.

Industrial Grade Durability

Designed for the heat and vibration of turbine decks, the 9905-376 maintains stable operation in temperatures up to 60 °C. The internal circuitry features high-grade isolation to protect the processor from electromagnetic interference, provided the installer maintains a grounding resistance of less than 4 Ω.

FAQs

Does the Woodward 9905-376 support both isochronous and droop modes?

Yes. The controller provides flexible speed control logic. You can select Isochronous mode for constant frequency in isolated grids or Droop mode for stable load sharing when paralleled with a utility utility.

Is this unit compatible with existing 505 series installations?

The 9905-376 acts as a direct replacement for various discontinued 505-series part numbers. However, because turbine dynamics vary, you must transfer and verify the PID tuning parameters from the old unit to the new digital module to ensure stable governor response.

What power supply is required for stable operation?

The unit operates on a wide DC range of 10–40 VDC (24V nominal). It consumes approximately 12 Watts. To prevent unexpected resets or communication drops, you must use a filtered, industrial-grade power source.

Can I configure this module for a split-range actuator setup?

Absolutely. The 9905-376 specifically includes logic to drive two separate actuator channels, making it ideal for turbines that utilize both a primary control valve and an extraction or admission valve.