ProAct II Actuator/Driver
Manual 04176
18
Woodward
Chapter 3.
Description of Operation
The ProAct control system functions by receiving a position command signal
from a Woodward electronic governor. The system then sends a pulse width
modulated current (–12 A to +12 A) signal to the actuator, modified by signals
from a position feedback, velocity, and current sensor from the actuator (Figure
3-1).
Figure 3-1. ProAct II Functional Block Diagram
Electronic Circuits
All circuits in the ProAct driver are solid state and are not serviceable in the field.
The printed circuit board is manufactured by Woodward to provide maximum
tolerance to temperature and vibration.
Four potentiometers, accessible when the cover of the driver box is removed,
provide all adjustments to the driver system.
A 25-turn pot (Position Command Gain) adjusts how far the actuator travels
when the speed control signal varies from minimum to maximum.
