Woodward EG-3P User manual

Product Manual 82560
(Revision R, 9/2018)
Original Instructions
EG-3P Actuator
including EG-1P, EG-3P with compensation,
EG-3P oil motor, and EG-3P oil pump
Installation and Operation Manual

General
Precautions
Read this entire manual and all other publications pertaining to the work to be
performed before installing, operating, or servicing this equipment.
Practice all plant and safety instructions and precautions.
Failure to follow instructions can cause personal injury and/or property damage.
Revisions
This publication may have been revised or updated since this copy was produced.
To verify that you have the latest revision, check manual 26455, Customer
Publication Cross Reference and Revision Status & Distribution Restrictions, on
the publications page of the Woodward website:
www.woodward.com/publications
The latest version of most publications is available on the publications page. If
your publication is not there, please contact your customer service representative
to get the latest copy.
Proper Use
Any unauthorized modifications to or use of this equipment outside its specified
mechanical, electrical, or other operating limits may cause personal injury and/or
property damage, including damage to the equipment. Any such unauthorized
modifications: (i) constitute "misuse" and/or "negligence" within the meaning of
the product warranty thereby excluding warranty coverage for any resulting
damage, and (ii) invalidate product certifications or listings.
Translated
Publications
If the cover of this publication states "Translation of the Original Instructions"
please note:
The original source of this publication may have been updated since this
translation was made. Be sure to check manual 26455, Customer Publication
Cross Reference and Revision Status & Distribution Restrictions, to verify whether
this translation is up to date. Out-of-date translations are marked with . Always
compare with the original for technical specifications and for proper and safe
installation and operation procedures.
Revisions—Changes in this publication since the last revision are indicated by a black line
alongside the text.
Woodward reserves the right to update any portion of this publication at any time. Information provided by Woodward is
believed to be correct and reliable. However, no responsibility is assumed by Woodward unless otherwise expressly
undertaken. Manual 82560
Copyright © Woodward 1983–2018
All Rights Reserved

Manual 82560 EG-3P Actuator
Woodward 1
Contents
WARNINGS AND NOTICES...........................................................................2
ELECTROSTATIC DISCHARGE AWARENESS .................................................3
REGULATORY COMPLIANCE .......................................................................4
CHAPTER 1. GENERAL INFORMATION..........................................................6
2301 Electric Governor...........................................................................................6
Proportional Actuators for 2301 Electric Controls ..................................................6
EG-3P Actuator ......................................................................................................7
EG-3P Actuator (with Compensation) ..................................................................10
CHAPTER 2. INSTALLATION ......................................................................14
Introduction...........................................................................................................14
Factory Adjustments.............................................................................................15
CHAPTER 3. TROUBLESHOOTING..............................................................19
CHAPTER 4. REPLACEMENT PARTS ..........................................................20
CHAPTER 5. PRODUCT SUPPORT AND SERVICE OPTIONS...........................27
Product Support Options......................................................................................27
Product Service Options.......................................................................................27
Returning Equipment for Repair...........................................................................28
Replacement Parts...............................................................................................28
Engineering Services............................................................................................29
Contacting Woodward’s Support Organization ....................................................29
Technical Assistance............................................................................................30
APPENDIX.PROTRACTOR.........................................................................31
REVISION HISTORY ..................................................................................32
DECLARATIONS .......................................................................................33
Illustrations and Tables
Figure 1-1. EG-3P Schematic.................................................................................9
Figure 1-2. EG-3PC Schematic............................................................................11
Figure 1-3. Needle Valve Location.......................................................................12
Figure 1-4. Parts for Compensation.....................................................................13
Figure 2-1. Recommended Actuator Output Shaft Travel Adjustment.................14
Figure 2-2. Actuator Test Circuit ..........................................................................16
Figure 4-1a. Exploded View (EG-3P with Gear Pump)........................................21
Figure 4-1b. Exploded View (EG-3P with Oil Motor)............................................22
Figure 4-2. Plug Location for Oil Pump ................................................................23
Figure 4-3. Outline Drawing (EG-3P with Gear Pump) ........................................24
Figure 4-4. Outline Drawing (EG-3P with Oil Motor)............................................25
Figure 4-5. Outline Drawing (EG-3P with Oil Pump)............................................26
Table 1-1. Typical Governor Oil Pressure vs Useful Work Output.........................8

EG-3P Actuator Manual 82560
2 Woodward
Warnings and Notices
Important Definitions
This is the safety alert symbol. It is used to alert you to potential
personal injury hazards. Obey all safety messages that follow this
symbol to avoid possible injury or death.
DANGER—Indicates a hazardous situation which, if not avoided, will result
in death or serious injury.
WARNING—Indicates a hazardous situation which, if not avoided, could
result in death or serious injury.
CAUTION—Indicates a hazardous situation which, if not avoided, could
result in minor or moderate injury.
NOTICE—Indicates a hazard that could result in property damage only
(including damage to the control).
IMPORTANT—Designates an operating tip or maintenance suggestion.
Overspeed /
Overtemperature /
Overpressure
The engine, turbine, or other type of prime mover should be
equipped with an overspeed shutdown device to protect against
runaway or damage to the prime mover with possible personal injury,
loss of life, or property damage.
The overspeed shutdown device must be totally independent of the
prime mover control system. An overtemperature or overpressure
shutdown device may also be needed for safety, as appropriate.
Personal Protective
Equipment
The products described in this publication may present risks that
could lead to personal injury, loss of life, or property damage. Always
wear the appropriate personal protective equipment (PPE) for the job
at hand. Equipment that should be considered includes but is not
limited to:
Eye Protection
Hearing Protection
Hard Hat
Gloves
Safety Boots
Respirator
Always read the proper Material Safety Data Sheet (MSDS) for any
working fluid(s) and comply with recommended safety equipment.
Start-up
Be prepared to make an emergency shutdown when starting the
engine, turbine, or other type of prime mover, to protect against
runaway or overspeed with possible personal injury, loss of life, or
property damage.
Automotive
Applications
On- and off-highway Mobile Applications: Unless Woodward's control
functions as the supervisory control, customer should install a
system totally independent of the prime mover control system that
monitors for supervisory control of engine (and takes appropriate
action if supervisory control is lost) to protect against loss of engine
control with possible personal injury, loss of life, or property damage.

Manual 82560 EG-3P Actuator
Woodward 3
Battery Charging
Device
To prevent damage to a control system that uses an alternator or
battery-charging device, make sure the charging device is turned off
before disconnecting the battery from the system.
Electrostatic Discharge Awareness
Electrostatic
Precautions
Electronic controls contain static-sensitive parts. Observe the
following precautions to prevent damage to these parts:
Discharge body static before handling the control (with power to
the control turned off, contact a grounded surface and maintain
contact while handling the control).
Avoid all plastic, vinyl, and Styrofoam (except antistatic versions)
around printed circuit boards.
Do not touch the components or conductors on a printed circuit
board with your hands or with conductive devices.
To prevent damage to electronic components caused by improper
handling, read and observe the precautions in Woodward manual
82715, Guide for Handling and Protection of Electronic Controls,
Printed Circuit Boards, and Modules.
Follow these precautions when working with or near the control.
1. Avoid the build-up of static electricity on your body by not wearing clothing
made of synthetic materials. Wear cotton or cotton-blend materials as much
as possible because these do not store static electric charges as much as
synthetics.
2. Do not remove the printed circuit board (PCB) from the control cabinet
unless absolutely necessary. If you must remove the PCB from the control
cabinet, follow these precautions:
Do not touch any part of the PCB except the edges.
Do not touch the electrical conductors, the connectors, or the
components with conductive devices or with your hands.
When replacing a PCB, keep the new PCB in the plastic antistatic
protective bag it comes in until you are ready to install it. Immediately
after removing the old PCB from the control cabinet, place it in the
antistatic protective bag.

EG-3P Actuator Manual 82560
4 Woodward
Regulatory Compliance
The listings in this section are limited to EG-3P units.
European Compliance for CE Marking:
These listings are limited only to those units bearing the CE Marking.
ATEX –Potentially Directive 2014/34/EU on the harmonization of the
Explosive laws of the Member States relating to equipment
Atmospheres and protective systems intended for use in
Directive: potentially explosive atmospheres.
Zone 1, Category 2, Group IIG Ex e II T6
TUV 15 ATEX 7717X
Other European and International Compliance:
Compliance with the following European Directives or standards does not qualify
this product for application of the CE Marking.
ATEX Directive: Exempt from the non-electrical portion of the ATEX
Directive 2014/34/EU due to no potential ignition
sources per EN 13463-1:2009 Category 2.
Pressure Compliant as “SEP” per Article 4.3 to Pressure
Equipment Equipment Directive 2014/68/EU on the
Directive: harmonization of the laws of the Member States
relating to the making available on the market of
pressure equipment.
Machinery Compliant at partly completed machinery with
Directive: Directive 2006/42/EC of the European Parliament
and the Council of 17 May 2006 on machinery.
IECEx: Certified for use in hazardous locations IECEx TUR
15.0024X
Ex e IIC T4 Gb
North American Compliance:
These listings are limited only to those EG-3P actuators bearing the CSA or UL
identification.
CSA: CSA Certified for Class I, Division 2, Groups A, B, C, & D, T4 at
93 °C Ambient. For use in Canada and the United States.
CSA 1987834
UL: UL Listed for Class I, Division 2, Groups B, C, & D, T4 at 93 °C
Ambient. For use in the United States.
UL File E158654
Special Conditions for Safe Use:
Wiring must be in accordance with North American Class I, Division 2 wiring
methods as applicable, and in accordance with the authority having jurisdiction.
Field wiring must be suitable for at least 125 °C.
Connect ground terminal to earth ground.

Manual 82560 EG-3P Actuator
Woodward 5
When used in a Zone 2 Hazardous location, the enclosure in which
the EG3P actuator is installed must provide a minimum IP54 level of
protection against ingress of dust and moisture in accordance with
EN 60079-15.
EXPLOSION HAZARD—Do not remove covers or connect/disconnect
electrical connectors unless power has been switched off or the area
is known to be non-hazardous.
Substitution of components may impair suitability for Class I,
Division 2 or Zone 2
RISQUE D’EXPLOSION—Ne pas enlever les couvercles, ni
raccorder / débrancher les prises électriques, sans vous en
assurez auparavant que le système a bien été mis hors
tension; ou que vous situez bien dans une zone non
explosive.
La substitution de composants peut rendre ce matériel
inacceptable pour les emplacements de Classe I, Division 2
et/ou Zone 2.

EG-3P Actuator Manual 82560
6 Woodward
Chapter 1.
General Information
2301 Electric Governor
The 2301 electric governor is one in which its actuator output (terminal) shaft
position is directly proportional to the input signal from its electric control unit. It
can be used in an isochronous (constant speed) mode for single engine
operation or when paralleled with similar units on an isolated bus. It can also be
used in the droop mode for paralleling dissimilar units or operating on an infinite
bus. The 2301 governor is used in the same type of service as many other
governor models. It is particularly well suited, when used with some types of
proportional actuators, to engines operated in tandem to drive a common load. In
such installations, one electric control is used to furnish the same input signal to
the proportional actuator on each engine. Since each actuator receives the same
current, their output shafts take the same position and give each engine the
same amount of fuel.
The 2301 electric governor consists of an electric control unit, a speed setting
potentiometer, and a hydraulic actuator. The electric control receives the input
signals to the governor; its output serves as the input signal to the actuator. The
actuator output controls the flow of energy medium to the prime mover. The
speed setting potentiometer, used to adjust speed setting, provides one of the
inputs to the electric control.
The operation of the 2301 type governor is different and distinct from other
electric governors. The steady-state output of the electric control is a level of
voltage determined by the actuator terminal shaft position required to maintain a
particular load on the prime mover. The voltage is always the same polarity. This
type of control unit requires an actuator in which the output shaft takes a position
proportional to the voltage of the input signal.
In contrast, the electric control unit of the EG series electric governor emits a
nominally zero signal during conditions of on-speed, steady-state operation, and
larger voltage signal only during off-speed or load-changing periods. In this type
of system, the direction of actuator operation depends on signal polarity.
As is the case with any type governor, the prime mover should be equipped with
a separate overspeed device to prevent runaway if a failure should render the
governor inoperative.
Proportional Actuators for 2301 Electric Controls
Among the proportional actuators used with the 2301 electric controls are:
EGB-2P Actuator
This is a proportional actuator that has a mechanical-hydraulic backup governor
section as well as an electric-signal-operated governor section. It must be driven
directly from the prime mover for speed sense to the flyweights and operation of
the governor oil pressure pump. The EGB-2P actuator has a stalled work
capacity of 2.5 ft-lb (3.4 J) at a 32° output shaft travel. Useful work capacity is
about 2/3 of stalled capacity.

Manual 82560 EG-3P Actuator
Woodward 7
EG-3P Actuator
This actuator has no mechanical-hydraulic backup governor. Some models
require a drive for an internal oil pump, but the rotation need not be proportional
to prime mover speed. These models can be mounted external to the prime
mover and driven by an electric motor or other device if no drive pad has been
furnished on the prime mover. Other models have an oil motor built into the
actuator. These units require pressure oil from an external source to operate the
oil motor and provide the working pressure needed by the actuator.
The EG-3P has 4.5 ft-lb (6.1 J) of stalled work capacity, a useful work capacity of
3 ft-lb (4 J), and a maximum 42° output shaft travel. Torque rating is 6.0 lb-ft (8.1
Nm).
2301 Actuator
The simplest of the proportional actuators, the 2301 actuator does not require a
drive of any kind, since there is no flyweight backup governor or pressure pump
contained in it. Hydraulic pressure fluid must be supplied from an external
source, such as the prime mover’s fuel oil or lubricating oil supply. Accepting fluid
pressures within a 15–100 psi (103–690 kPa) range, the 2301 actuator will
supply 0.166 ft-lb (0.225 J) of stalled work capacity for each 10 psi (69 kPa)
hydraulic pressure input (useful work is about 2/3 of stalled capacity), through an
angular output shaft travel of 30°. Torque is 0.32 lb-ft (0.43 Nm) per each 10 psi
(69 kPa) input.
In applications involving unattended cold starting, an EG-type actuator is
recommended unless fuel oil with its low viscosity is available as the pressure
source for the 2301 actuator. Most lubricating oils are suitable for controlling the
2301 actuator when oil is at operating temperature. Viscosity of hydraulic fluid
above 1000 SUS during cold start will temporarily cause the actuator to operate
erratically.
This manual describes the EG-3P actuator, which may be used with any of the
2301 electric controls. Other manuals describe the other actuators and the
electric controls available to operate proportional actuators.
EG-3P Actuator
Description
The essential element of the EG-3P actuator is an electro-hydraulic transducer
which controls oil flow to and from the power piston through the action of a
polarized solenoid. The position of the terminal shaft on the EG-3P actuator is
proportional to the input current to the solenoid coil controlling the hydraulic pilot
valve plunger.
The EG-3P actuator has a stalled work capacity of 4.5 ft-lb (6.1 J) at 400 psi
(2758 kPa), a useful work capacity of 3 ft-lb (4 J), and a stalled torque rating of
6.0 lb-ft (8.1 Nm) transmitted through an output shaft rotation of 42°.
Table 1-1 shows a list of typical governor oil pressures versus useful work output.
The output is proportional to the pressure input, and applies to the oil motor
model only. The oil pump model operates at 400 psi (2758 kPa) for 3 ft-lb (4 J) of
useful work output.

EG-3P Actuator Manual 82560
8 Woodward
Actuator Operating Useful
Oil Pressure Work Output
400 psi (2758 kPa) 3.00 ft-lb (4.07 J)
300 psi (2068 kPa) 2.25 ft-lb (3.05 J)
200 psi (1379 kPa) 1.50 ft-lb (2.03 J)
100 psi (690 kPa) 1.00 ft-lb (1.36 J)
Table 1-1. Typical Governor Oil Pressure vs Useful Work Output
For emergency start-ups, Woodward recommends an oil sump to furnish
immediate oil to the actuator.
The EG-3P actuator normally goes to minimum fuel if the electric signal is
interrupted. Oil for the EG-3P actuator is taken from the engine lubricating
system or from a separate sump (not furnished by Woodward).
An EG-3P actuator can be furnished with or without a drive shaft. The drive shaft
of a unit fitted with such a shaft can be driven by the prime mover or some other
means to provide relative rotation between the pilot valve plunger and bushing
and to rotate the oil pump gears. The drive shaft should rotate between 1200 and
3600 rpm. It can rotate in one direction only. The direction of rotation is
determined by the placement of plugs in the oil passages in the actuator base
and case. A relief valve is incorporated within the actuator to maintain the
operating oil pressure at approximately 350 psi (2413 kPa) above supply
pressure.
An EG-3P actuator not fitted with a drive shaft is equipped with an oil motor.
Actuators with oil motors do not have oil pumps. Oil under pressure must be
supplied to provide working pressure for the actuator and to operate the oil motor
which rotates the pilot valve bushing. Oil supply to the Oil Motor is restricted by
an orifice. The size of the orifice depends upon the pressure supplying the unit
on the following scale:
Supply Pressure Orifice Diameter
80 to 99 psi (552 to 687 kPa): 0.076” (1.93 mm) dia.
100 to 175 psi (688 to 1210 kPa): 0.062” (1.57 mm) dia.
176 to 300 psi (1211 to 2071 kPa): 0.055” (1.40 mm) dia.
301 to 500 psi (2072 to 3448 kPa): 0.047” (1.19 mm) dia.
The orifice size is supplied inside most of the actuators at the time of purchase
and is matched to the specified supply pressure.
Some actuators are designed to have a separate supply line to the oil motor and
in these instances the orifice is placed in the connection to the oil motor rather
than in an internal oil passage.
Work output of the EG-3P actuator equipped with an oil motor depends upon the
pressure of the oil supplied to the actuator. With a 400 psi (2758 kPa) supply
pressure, the actuator output would be 4.5 ft-lb (6.1 J).
Operation
Oil from the external source enters the suction side of the oil pump. The pump
gears carry the oil to the pressure side of the pump, first filling the oil passages
and then increasing the hydraulic pressure. When the pressure becomes great
enough to overcome the relief valve spring force and push the relief valve
plunger down to uncover the bypass hole, the oil recirculates through the pump.

Manual 82560 EG-3P Actuator
Woodward 9
The movement of two opposing pistons rotates the actuator terminal shaft. The
prime mover fuel (or steam) linkage is attached to the terminal shaft.
Pressure oil from the pump is supplied directly to the underside of the loading
piston. Pressure in this hydraulic circuit always tends to turn the terminal shaft in
the “decrease fuel” direction.
Since the linkage that connects the loading piston to the terminal shaft is shorter
than the linkage that connects the power piston to the terminal shaft, the loading
piston cannot move up unless the power piston moves down. The power piston
moves down only when the oil trapped beneath it escapes to sump.
The flow of oil to and from the power piston is controlled by the pilot valve
plunger. With the pilot valve plunger centered, no oil flows to or from the power
piston. The pilot valve plunger is centered when its control land exactly covers
the control port in the pilot valve bushing.
The greater of two forces moves the pilot valve plunger up or down. When the
forces are equal, the plunger does not move.
Figure 1-1. EG-3P Schematic

EG-3P Actuator Manual 82560
10 Woodward
The pilot valve plunger is connected to a permanent magnet that is spring-
suspended in the field of a two-coil solenoid. The output signal from the electric
control box is applied to the solenoid coils and produces a force, proportional to
current in the coils, which tends always to move the magnet—and pilot valve
plunger—down.
A spring force tends always to move the pilot valve plunger and magnet up. The
centering spring sits atop the case in which the solenoid coils are located. It
exerts a constant upward force on the pilot valve plunger. The restoring spring
exerts a downward force on the pilot valve plunger. The downward force from the
restoring spring depends upon the position of the restoring lever. The restoring
lever moves up to decrease the restoring spring force as the terminal shaft
rotates in the “increase” fuel (or steam) direction. The resultant force from the
combined output of the centering spring and restoring spring is a force that is
always urging the pilot valve plunger in the “up” direction; this resultant force
increases as the terminal shaft moves in the “increase” fuel (or steam) direction.
With the unit running on-speed under steady-state conditions, the resultant
spring force and force from the current in the solenoid coils are equal but
opposite.
Assume the unit is running on-speed under steady-state conditions. The pilot
valve plunger is centered. A decrease in voltage input to the solenoid coils—due
to a decrease in speed setting or a decrease in load—decreases the force
tending to lower the pilot valve plunger. Consequently, the unchanged spring
force is now greater and lifts the plunger above center. As oil escapes from under
the power piston, the terminal shaft rotates in the “decrease” fuel (or steam)
direction. When the terminal shaft has rotated far enough to satisfy the new fuel
requirement, the increase in restoring spring force will “equal” the decrease in
downward force from the current in the solenoid coils, and the pilot valve plunger
will be re-centered by the again equal but opposite forces acting upon it.
Were the voltage signal input to the solenoid coils increased—due to an increase
in load or an increase in speed setting—similar but opposite reactions would
occur. The now greater downward force from the solenoid coils would move the
pilot valve plunger down. The power piston and restoring lever would be moved
up, decreasing the downward force of the restoring spring. When the terminal
shaft would have rotated far enough to satisfy the new fuel requirement, the
decrease in restoring spring force would “equal” the increase in downward force
from the current in the solenoid coils and the pilot valve plunger would be re-
centered by the again equal but opposite forces acting upon it.
EG-3P Actuator (with Compensation)
Description
Many EG-3P actuators operate with oil supplied directly from the prime mover.
Certain multi-viscosity motor oils require a compensation system within the
actuator to provide needed stability.
The EG-3 proportional actuator can be supplied from the factory with a
compensation system. The compensation system will supply extra hydraulic
pressure to the pilot valve plunger to assist the plunger’s return to a normal,
centered position following a fuel change. Figure 1-2 is a schematic of the
compensation system.

Manual 82560 EG-3P Actuator
Woodward 11
Figure 1-2. EG-3PC Schematic
Buffer System
With a fuel change, the new position taken by the loading piston changes the
pressure of the compensation oil, temporarily. The new pressure causes a
pressure difference across the compensation land and this assists in re-centering
the plunger. The buffer piston is also displaced by the pressure difference and
this energy is stored in the buffer springs. As the engine returns to speed, the
pressure difference stored by the buffer system is dissipated through the needle
valve.
EG-1P and EG-1PC
The EG-1 P and EG-1 PC (with compensation) actuators offer reduced work
output and faster response time than the EG-3 units. The quick response
variation is built in both the oil pump and oil motor model.

EG-3P Actuator Manual 82560
12 Woodward
All adjustment, maintenance and other information contained in this manual is
equally applicable to the EG-1 model. Many parts are interchangeable. Since
part designations in this manual are reference numbers, not actual part numbers,
parts for the EG-1 may be ordered from this manual as well as parts for the
EG-3P and EG-3PC actuators.
Needle Valve Adjustment
The needle valve is factory set at two turns out from closed. If instability is
experienced during operation with cold multi-viscosity oils the needle valve can
be turned in until stability is obtained. The actuator should not be run at a needle
valve opening of less than one turn out from closed as response would not be
acceptable. A wider needle valve opening provides quicker actuator response but
less stability. This adjustment must be made at startup, before engine oil warms
up. See Figure 1-3 for the needle valve location.
Figure 1-3. Needle Valve Location

Manual 82560 EG-3P Actuator
Woodward 13
Parts
Six additional parts are added to the base for the EG-proportional-compensated
actuator. The configuration of the base is also slightly changed. The additional
parts are shown in Figure 1-4. A needle valve with O-ring is added to the case.
Ref. No. Part Name .............................Quantity
82560-107 Snap Ring ...........................................1
82560-108 Buffer Plug ..........................................1
82560-109 O-ring..................................................1
82560-110 Buffer Spring.......................................2
82560-111 Buffer Piston........................................1
82560-112 O-ring..................................................1
82560-113 Needle Valve.......................................1
Figure 1-4. Parts for Compensation
If the unit will not be activated within three months of delivery, place
an adequate desiccant in the packing to help keep the actuator free
of rust formation.

EG-3P Actuator Manual 82560
14 Woodward
Chapter 2.
Installation
Introduction
Take care to mount the actuator “square” with the engine (or turbine) linkage.
If the actuator is one driven by the engine or some other source, a gasket should
be placed between the base and the base mounting pad. The gasket must not
block the two drain holes adjacent to the centering pilot of the base (see Figure
4-3).
Seal the oil supply hole in the base with a gasket when it is not being
used. See Figure 4-5, Note 2.
Oil draining through the drive shaft bore must flow freely to sump. The splined
drive shaft must fit into the drive with a free, slip fit; no tightness is permitted. The
actuator must drop onto the mounting pad of its own weight without applying
force.
Horizontal mounting configurations are provided with a drain in the cover (Figure
4-1 parts 83 and 84). Drain through the base is plugged.
Jumper wire connections C and D of the mating connector to the actuator (see
Figures 4-3 and 4-4).
Linkage Attachments
Adjustment of the fuel linkage must provide for control of fuel from “OFF” to
“FULL FUEL” within the limits of the 42° of actuator output shaft travel. It must
also provide for approximately 28° output shaft travel between “NO LOAD” and
“FULL LOAD,” (See Figure 2-1).
The engine linkage must be free of binding and without backlash. If there is a
collapsible member in the linkage, be sure it does not yield each time the
actuator moves the linkage rapidly.
Figure 2-1. Recommended Actuator Output Shaft Travel Adjustment

Manual 82560 EG-3P Actuator
Woodward 15
Maximum work capacity over full governor travel of 42° is *. See
Figure 2-1 for recommended governor output travel. In special
applications, min and max prime mover stops may be outside the
governor stops.
*—See Table 1-1 for values.
Be sure to allow sufficient overtravel at each end of the output shaft
so that the actuator can shut down the prime mover and also give
maximum fuel when required.
Shaft Driven Oil Supply
A 3/8” (~9.5 mm) OD tubing oil line must be connected from the oil supply to
either of two 1/8” (~3.2 mm) pipe tapped inlet holes in the actuator case. A
minimum of 5 psi (34 kPa) oil pressure is required at the actuator end of the line.
If a separate sump is used (rather than engine lubricating oil), the lift head must
not exceed 12” (30 cm) and a foot valve should be used.
Oil Motor Oil Supply
A 3/8” (~9.5 mm) OD tubing oil line must be connected to the inlet hole in the
case. See Figure 4-4. Some actuators require an additional 3/8” (~9.5 mm)
supply through an appropriate orifice directly to the oil motor.
Oil Supply Filtration
Shaft-driven oil-pump models require a 20 to 25 µm (nominal) filter in the oil-
supply line. This fitter is omitted in units supplied directly from the motor through
the base.
Oil motor models require a 10 to 15 µm (nominal) filter in the oil supply line.
To avoid possible damage to the actuator the units must not be run with the filter
off or bypassed.
Factory Adjustments
Make the following adjustments on a bench with the proper
equipment. All adjustments are preset at the factory to the proper
specification for your part number.

EG-3P Actuator Manual 82560
16 Woodward
Pilot Valve Centering
Refer to Figure 4-1b (oil motor model), for the item numbers used in the following
information. Initial adjustment consists of physically centering the magnet (74)
between the coils of the transducer (100) when the control land on the pilot valve
plunger (81) is centered over the control port in the pilot valve bushing (26). This
minimizes the effect of temperature drift when changes occur in the operating
temperature of the actuator.
Figure 2-2. Actuator Test Circuit
Bottom the centering screw (71) very gently to prevent damage to the
centering springs in the coil cover.
Center the pilot valve plunger as follows:
1. Connect the test circuit to the terminal block on the actuator as shown in
Figure 6. Set the test switch to OFF.
2. Install and secure the protractor (see Appendix) over the terminal shaft.
Install the actuator terminal lever for use as an indicator. Rotate the terminal
shaft over its full range of travel. Note or mark the minimum and maximum
shaft positions on the protractor. The total terminal shaft travel should be 42
to 45 degrees.
The magnet is centered at the factory and seldom needs to be
readjusted. Do not change this adjustment unless thoroughly familiar
with the adjustment procedure.
3. Insert a 7/64 inch Allen wrench through the clearance hole in the center of the
cover, through the hollow center of the adjustable spring seat (70), and
engage the centering screw (71). Turn the centering screw CW until it bottoms
GENTLY, then CCW 1 3/4 to 2 turns to establish an initial starting position.
For an oil pump unit, drive the unit on the test stand at any speed
between 1200 to 3600 rpm.
For an oil motor unit, mount it on the test stand, turn on the oil
supply and allow a few minutes for the actuator to warm up to
operating temperature. Make certain the oil motor is operating by
observing if the splined end of the pilot valve bushing is rotating.

Manual 82560 EG-3P Actuator
Woodward 17
4. Set the test switch to CENTER and adjust the potentiometer for 400 mA on
the milliammeter. Set the test switch to OFF.
5. Insert a 1/8 inch Allen wrench through the clearance hole in the center of the
cover, and engage the adjustable spring seat. Center the terminal shaft at
the approximate mid point of its travel. Turn the spring seat CW to move the
terminal shaft in the increase fuel direction or CCW to move the terminal
shaft in the decrease fuel direction. Note the exact position of the terminal
shaft for future reference.
6. Set the test to CENTER and observe the terminal shaft for rotation. If
necessary, readjust the potentiometer for 400 mA.
If the terminal shaft remains stationary, when shifting from 0 to 400 mA, the
pilot valve plunger is centered and no further centering adjustments are
required.
If the terminal shaft moves to another position when switching from OFF to
CENTER, note the direction of movement and then set the test switch to
OFF.
7. If the terminal shaft moves in the increase fuel direction, turn the pilot valve
centering screw CW a small amount using the 7/64 inch Allen wrench. If the
terminal shaft movement was in the decrease fuel direction, turn the
centering screw CCW.
Note the new position of the terminal shaft for reference if further adjustment
is required.
8. Repeat steps 6 and 7 until no movement of the terminal shaft occurs when
the test switch is moved from OFF to CENTER.
9. Set the test switch to OFF and turn the potentiometer fully CCW (decrease).
Terminal Shaft Travel
1. Remove cover (6 on Figure 4-1b) for access to feedback bracket (47).
Fasten sub cap (8) to case (22) with shorter screws.
2. Set the test switch to normal.
3. Adjust the potentiometer to 20 mA.
Check carefully that the Allen wrench being used to set the
adjustable spring seat is 1/8 inch. Should an undersized Allen
wrench be used, the centering adjustment could be changed, putting
the actuator completely out of adjustment. DO NOT USE AN
UNDERSIZE WRENCH.
4. Using a 1/8 inch Allen wrench, turn the ad just-able spring seat CCW until
the actuator terminal lever is at its minimum fuel position, then turn the seat
CW until the shaft moves 2° to 3° from its minimum fuel position towards
maximum fuel position.

EG-3P Actuator Manual 82560
18 Woodward
5. Adjust the potentiometer for 160 mA. The terminal shaft should move an
additional 36 (±1/2) degrees in the increase fuel direction.
To increase terminal shaft travel, move the feedback bracket pivot
pin (47) towards the terminal shaft.
6. Repeat the adjustments at minimum and maximum current alternately, until
no further adjustment is required at either point and 36 (±1/2) degrees
rotation is obtained.
7. Replace the cover.
8. Recheck the range and if adjustment is required, adjust spring seat (70)
through the vent hole in the cover. Use a 1/8 inch Allen wrench to make this
adjustment.
9. Disconnect the test circuit and the oil supply line if used. Remove the
protractor.
Control Box
Set the gain and reset controls on the control box at their mid-positions and the
speed setting potentiometer at minimum speed. Start the engine using the speed
setting potentiometer to bring the speed to the speed-no-load level.
Be ready to manually overcome the actuator output shaft in case the
speed setting potentiometer is connected to call for maximum rather
than minimum speed.
Stability is achieved through adjustment of the reset-droop and the gain controls.
After achieving stability turn the gain control clockwise until unstable. Now
readjust the reset-droop control until stability is achieved again. The objective is
to have the gain control as far clockwise as possible while still maintaining stable
operation.
In units designated EGB-3PC, a needle valve is present in the case (see Figure
4-3). The needle valve normally operates at two turns out from closed. If stability
cannot be obtained at this setting close the valve slightly. The needle valve must
be set at least one turn out from closed to provide satisfactory operation. Now
readjust the reset-droop control until stability is achieved again. The objective is
to have the gain control as far clockwise as possible while still maintaining stable
operation.
The shaft-driven EG-3P actuator (most often used) requires about 3/4 volt to
move the terminal shaft from the minimum stop. Six or seven volts are required
to move the terminal shaft to maximum stop. Some EG-3P actuators require less
voltage for full travel.