Product Overview

The Woodward 9905-860 serves as a high-performance digital speed control unit within the Peak 150 and 2301D product families. This module provides full-authority governing for steam turbines and heavy-duty industrial engines. By executing advanced digital algorithms, the 9905-860 maintains precise RPM stability, manages complex load transients, and enforces critical overspeed protection. It supports both isochronous and droop modes, enabling high-fidelity frequency control for isolated grids or stable load sharing in parallel utility operations. We supply this unit as 100% Brand New and Original, ensuring your mission-critical power generation or mechanical drive systems utilize the latest factory-spec digital processing.

Technical Specifications

The 9905-860 delivers deterministic governing through a versatile, high-speed digital architecture.

Engineering Advantages

The Woodward 9905-860 solves modern governing challenges through specialized digital features:

• Adaptive Transient Response: Unlike traditional analog governors, the 9905-860 utilizes programmable PID dynamics. This allows engineers to tune the response specifically for steam turbine inertia, preventing "hunting" during sudden load sheds and maintaining frequency within tight tolerances.

• Galvanic Isolation Protection: The module features extensive internal galvanic isolation. This shielding prevents electrical noise from marine propulsion systems or large variable frequency drives (VFDs) from corrupting the speed sensing signal, ensuring the CPU operates on clean, validated data.

• Dual Mode Flexibility: The unit seamlessly toggles between Isochronous and Droop modes via discrete inputs. This allows a single turbine to function as the lead frequency reference in a microgrid or as a contributing member of a larger utility parallel without hardware reconfiguration.

• Comprehensive Service Diagnostics: By utilizing the Woodward Watch Window software via the RS-232/485 service ports, technicians can perform real-time data logging and trend analysis. This facilitates proactive maintenance and rapid troubleshooting of fuel valve or actuator issues before they cause a system trip.

FAQs

Is the Woodward 9905-860 a direct replacement for older 2301A analog units?

The 9905-860 (2301D series) provides a digital upgrade path for many 2301A applications. While it offers superior accuracy and programmable features, you must verify the wiring and actuator compatibility, as the digital platform requires software-based configuration via a PC rather than manual potentiometer adjustments.

What speed sensors work with this module?

The 9905-860 accepts signals from standard Magnetic Pickups (MPU) or active Proximity Probes. The digital input circuitry filters high-frequency interference to ensure accurate RPM tracking up to 10,000 Hz.

Does this unit ship with pre-loaded software?

We supply the unit as Brand New factory hardware. You must configure the specific control parameters (RPM range, PID constants, and I/O mapping) using Woodward’s Watch Window software to match your specific turbine or engine application.

Can I monitor the 9905-860 remotely?

Yes. You can use the configurable 4–20 mA analog output to send speed or load feedback to a remote PLC or DCS. Additionally, the RS-485 port facilitates integration into wider industrial networks for digital telemetry and status monitoring.