9905-678
May 26, 2026

9905-678

Woodward 9905‑678 is a high‑performance digital speed‑load controller of the 9905 series, engineered for diesel/gas engines, steam/gas turbines and generator sets. It integrates precise speed governing, load regulation, overspeed protection and fault diagnosis, widely applied in power generation, petrochemical, oil‑gas and marine heavy‑duty industrial fields.

Description

Core Functions

  1. Two control modes: isochronous mode for single‑unit constant‑speed operation; droop mode for parallel load sharing of multiple units.

  2. PID closed‑loop control, with functions of critical speed avoidance, valve stroke limitation, startup ramp control and load rejection protection.

  3. Independent overspeed monitoring, real‑time self‑diagnosis, fault recording and multi‑channel relay alarm output.

  4. 4‑20 mA analog remote given signal, compatible with upper‑level DCS/PLC systems.

  5. Local panel parameter setting and online debugging through dedicated Woodward configuration software.

Electrical Specifications

  • Power Supply: 24 VDC (wide voltage range: 18–40 VDC)

  • Speed Input: Magnetic Pickup (MPU) sensor signal

  • Actuator Output: PWM driving signal for hydraulic/electric actuators

  • I/O: Programmable 4‑20 mA analog I/O, multi‑channel digital contact I/O

  • Communication: RS‑232 / RS‑485, Modbus‑RTU protocol

  • Safety Certification: Class 1 Div 2 hazardous area certification, industrial‑grade anti‑interference

Environmental & Mechanical Features

  • Operating Temperature: −40 °C ~ +85 °C

  • Mounting Type: Panel mounting

  • Housing: Rugged metal shell, dust‑proof and corrosion‑resistant

Typical Applications

  • Speed and load control of engine & turbine generator sets

  • Power plants, petrochemical plants, oil & gas compressor control systems

  • Prime mover control for marine auxiliary power generation

  • Industrial prime mover governing and safety protection systems


Get a Quote