Woodward UG-25+ User manual

Product Manual
26580
(Revision D, 9/2018
)
Original Instructions
UG-25+ Actuator
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 Out-of-date translations are marked with .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—A bold, black line alongside the text identifies changes in this publication since the
last revision.
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 26580
Copyright © Woodward, Inc. 2011 - 2018
All Rights Reserved

Manual 26580 UG-25+ Actuator
Woodward 1
Contents
WARNINGS AND NOTICES..............................................................................................................3
ELECTROSTATIC DISCHARGE AWARENESS ....................................................................................4
REGULATORY COMPLIANCE ..........................................................................................................5
CHAPTER 1. GENERAL INFORMATION.............................................................................................7
How to Use This Manual...............................................................................................................................7
General Description ......................................................................................................................................7
Operational Features ....................................................................................................................................7
Inputs / Outputs.............................................................................................................................................7
Available Drive Shafts...................................................................................................................................7
Available Terminal Shafts .............................................................................................................................7
UG Governor Similarities .............................................................................................................................. 8
Hydraulic Pump.............................................................................................................................................8
References....................................................................................................................................................8
Serviceability.................................................................................................................................................8
CHAPTER 2. MECHANICAL INSTALLATION ....................................................................................12
Introduction..................................................................................................................................................12
Initial Operation...........................................................................................................................................12
Unpacking ...................................................................................................................................................13
Drive Shaft Rotation....................................................................................................................................15
Drive Connection.........................................................................................................................................17
Oil Supply....................................................................................................................................................19
Heat Exchanger ..........................................................................................................................................22
Recommended Service Intervals................................................................................................................22
CHAPTER 3. ELECTRICAL INSTALLATION......................................................................................23
Introduction..................................................................................................................................................23
Unit Grounding............................................................................................................................................23
Shielded Wiring...........................................................................................................................................24
Electrical Connections.................................................................................................................................24
High Potential Testing.................................................................................................................................35
Insulation Resistance Testing.....................................................................................................................35
CHAPTER 4. DESCRIPTION OF OPERATION...................................................................................37
General........................................................................................................................................................37
Principal of Operation..................................................................................................................................38
Fault Detection and Annunciation...............................................................................................................40
Shutdown Details ........................................................................................................................................40
CHAPTER 5. TROUBLESHOOTING.................................................................................................42
Introduction..................................................................................................................................................42
General System Troubleshooting Guide.....................................................................................................42
CHAPTER 6. PRODUCT SUPPORT AND SERVICE OPTIONS .............................................................46
Product Support Options.............................................................................................................................46
Product Service Options .............................................................................................................................46
Returning Equipment for Repair .................................................................................................................47
Replacement Parts......................................................................................................................................48
Engineering Services ..................................................................................................................................48
Contacting Woodward’s Support Organization...........................................................................................48
Technical Assistance ..................................................................................................................................49
APPENDIX A. ACRONYMS /ABBREVIATIONS.................................................................................50
APPENDIX B. UG-25+ GOVERNOR SPECIFICATIONS .....................................................................51

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REVISION HISTORY .....................................................................................................................54
DECLARATIONS ..........................................................................................................................55
Illustrations and Tables
Figure 1-1a. UG-25+Actuator Outline Drawing......................................................9
Figure 1-1b. UG-25+Actuator Outline Drawing....................................................10
Figure 1-2. UG-25+Drive Shaft Configurations....................................................11
Figure 2-1. UG-25+Actuator Overview................................................................14
Figure 2-2. Proper Drive Shaft Rotation...............................................................15
Figure 2-3. Terminal Shaft Travel ........................................................................18
Figure 2-4. Linear Linkage...................................................................................19
Figure 2-5. Non-linear Linkage ............................................................................19
Figure 2-6. Oil Chart.............................................................................................20
Figure 3-1. Location of Ground Strap ..................................................................23
Figure 3-2. Access Cover Instruction Label.........................................................25
Figure 3-4. Correct and Incorrect Dome Nut Installation.....................................26
Figure 3-5. UG-25+Actuator Application Wiring ..................................................27
Figure 3-6a. Connector Wiring.............................................................................28
Figure 3-6b. Connector Wiring.............................................................................29
Figure 3-6c. Connector Wiring.............................................................................30
Figure 3-6d. UG-25+Actuator Terminals .............................................................31
Figure 3-4. Internal Block Diagram ......................................................................33
Figure 3-5. Correct and Incorrect Wiring to Power Supply..................................34
Figure 3-6. Relay Driver Output...........................................................................34
Figure 4-1. UG-25+Actuator Front Panel.............................................................37
Figure 4-2. UG-25+Actuator Functional Overview...............................................39
Table 3-1. Customer I/O Terminal Position Assignment.............................................................................32
Table 5-1. Engine/Generator Troubleshooting............................................................................................44
Table B-1. Power Input (1 and 2)................................................................................................................53
Table B-2. Status (Unit Health) Output.......................................................................................................53
Table B-3. Position Command....................................................................................................................53

Manual 26580 UG-25+ Actuator
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Warnings and Notices
Important Definitions
This is the safety alert symbol 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.

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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.

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Regulatory Compliance
European Compliance for CE Marking:
These listings are limited only to those units bearing the CE Marking.
EMC Directive
Declared to Directive 2014/30/EU of the European Parliament and of the
Council of 26 February 2014 on the harmonization of the laws of the
Member States relating to electromagnetic compatibility (EMC).
Other European Compliance
Compliance with the following European Directives or standards does not qualify this product for
application of the CE Marking:
Machinery Directive:
Compliant as partly completed machinery with Directive 2006/42/EC of the
European Parliament and the Council of 17 May 2006 on machinery.
Pressure Equipment
Directive:
Compliant as “SEP” per Article 4.3 to Pressure Equipment Directive
2014/68/EU on the harmonisation of the laws of the Member States
relating to the making available on the market of pressure equipment.
Marine Compliance:
Type Approval with the following Marine Classification Societies:
ABS:
2007 Steel Vessel Rules 1-1-4/7.7.4-9-7/13.1
BV:
BV Rules for the Classification of Steel Ships
CCS:
Part 3, Chapter 9; Part 7, Chapter 2 of CCS "Rules for Classification of
Sea-going Steel Ships" (2009) and its 2010/2011 Amendments
DNV GL:
Det Norske Veritas Rules for Classification of Ships, High Speed & Light
Craft and Det Norske Veritas Offshore Standards
KRS:
Korean Register of Shipping Pt. 6 Ch. 2 Art. 301 of the Rules for
Classification, Steel Ships
LR:
Lloyds Register Environmental Categories ENV1, ENV2, ENV3, and ENV4
as defined in LR Test Specification No.1: 2002
NK:
Nippon Kaiji Kyokai requirements Chapter 1, Part 7 of Guidance for the
approval and type approval of materials and equipment for marine use and
relevant Society's Rules
Special Conditions for Safe Use:
Field wiring must be suitable for at least 55 °C.
Compliance with the Machinery Directive 2006/42/EC noise measurement and mitigation requirements is
the responsibility of the manufacturer of the machinery into which this product is incorporated.

Manual 26580 UG-25+ Actuator
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Safety Symbols
Direct Current
Alternating Current
Both Alternating and Direct Current
Caution, risk of electrical shock
Caution, refer to accompanying documents
Protective conductor terminal
Frame or chassis terminal

Manual 26580 UG-25+ Actuator
Woodward 7
Chapter 1.
General Information
How to Use This Manual
The following summarizes how to install a UG-25+actuator into a new or existing system:
•Unpack and inspect the hardware.
•Mount and wire the hardware following the procedures and recommendations in Chapters 2–3.
•Specifications and Troubleshooting information are provided in the Appendixes.
General Description
The Woodward UG-25+actuator is a microprocessor controlled mechanical hydraulic actuator used in
conjunction with an external governor for controlling diesel, gas, or dual fuel engines, or steam turbines.
The UG-25+actuator provides a fast-acting and high-work-output actuator, without the need for any
auxiliary devices such as a start booster or oil cooler.
The UG-25+actuator uses an internal, self-contained oil system operating at 1034 kPa (150 psi) internal
pressure with an internal oil pump driven from the actuator's drive shaft. Oil pressure is maintained by a
relief valve system with a drain to an internal oil sump.
Operational Features
The UG-25+actuator terminal shaft assumes a position which is directly proportional to the (4 to 20) mA
analog input signal.
Inputs / Outputs
The following inputs and outputs are available:
•Input Power (single or dual)
•Unit Healthy Status discrete output
•Analog (4 to 20) mA input controlling terminal shaft position
Available Drive Shafts
The following drive shafts are available:
Standard—
0.625–36 serrated drive shaft
0.625 keyed drive shaft with 0.625-18 thread
Available (for special applications at additional cost)—
Extended 0.625 keyed drive shaft
Available Terminal Shafts
The following output terminal drive shafts are available:
Standard—
0.625–36 serrated terminal shaft (25 ft-lb version only)
0.750-48 serrated terminal shaft (31 ft-lb version only)

Manual 26580 UG-25+ Actuator
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Available (for special applications at additional cost)—
0.562 / 0.625 D-shaped terminal shaft
UG Governor Similarities
The base is designed to fit any engine drive designed for a UG8 governor. The terminal shaft location
relative to the mounting base is similar to a UG8 governor.
Hydraulic Pump
The UG-25+actuator is equipped with a Gerotor fixed displacement pump (similar to the 3161 governor
type) with a relief valve. The pump/relief valve uses oil from its self-contained sump to provide 1035 kPa
(150 psi) internal operating pressure.
Two displacements are offered to cover the speed range up to 1700 grpm. The large displacement pump
(22.22 mm / 0.875 inch thick) is intended to be used with actuator drive speeds from 350 to 1200 rpm.
Running the large displacement pump continuously above 1200 grpm will result in excessive oil
temperatures. The small displacement pump (15.88 mm / 0.625 inch thick) is designed to be used with
drive speeds between 500 and 1700 rpm maximum continuous operation.
The direction of rotation is selected by pump housing alignment. The pump operates in the selected
direction only. The drive uses a maximum of 335 W (0.45 hp).
References
The following publications provide additional information about installation, operation, and storage of
Woodward products. All are available on the Woodward website (www.woodward.com).
Publication
25071 Oils for Hydraulic Controls
25075 Commercial Preservation Packaging for Storage of Mechanical-Hydraulic Controls
50516 Governor Linkage for Butterfly Control Valve
03386 UG-25+Actuator Product Specification
36684 Booster Servomotor
Contact your nearest Woodward Distributor or Authorized Independent Service Facility about repairs.
Serviceability
The UG-25+actuator has no field-replaceable parts.
The UG-25+actuator is not equipped with an overspeed trip function.
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.

Manual 26580 UG-25+ Actuator
Woodward 9
Figure 1-1a. UG-25+Actuator Outline Drawing

Manual 26580 UG-25+ Actuator
Woodward 10
Figure 1-1b. UG-25+Actuator Outline Drawing

Manual 26580 UG-25+ Actuator
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Figure 1-2. UG-25+Drive Shaft Configurations

Manual 26580 UG-25+ Actuator
Woodward 12
Chapter 2.
Mechanical Installation
Introduction
This chapter describes receiving, storage, and installation requirements for the UG-25+ actuator.
Due to typical noise levels in turbine or engine environments,
hearing protection should be worn when working on or around the
UG-25
+
actuator.
The surface of this product can become hot enough or cold enough
to be a hazard. Use protective gear for product handling in these
circumstances. Temperature ratings are included in the specification
section of this manual.
Use of an independent device for positive shutdown, such as a fuel
shut-off valve, is highly recommended. Failure to comply with this
recommendation can cause personal injury and/or property damage.
Use of an external spring to return to minimum fuel is highly
recommended. Failure to comply with this recommendation can
cause personal injury and/or property damage.
Use of a predicted minimum fuel shutdown procedure is highly
recommended. Failure to comply with this recommendation can
cause personal injury and/or property damage.
Use care while handling and installing the UG-25+actuator. Be
particularly careful to avoid striking the drive shaft, terminal shaft, or
the electrical connector. Abuse can damage seals, internal parts, and
factory adjustments. Do not set the actuator on its drive shaft.
External fire protection is not provided in the scope of this product. It
is the responsibility of the user to satisfy any applicable
requirements for their system.
Initial Operation
Before initial operation of the engine equipped with a UG-25+actuator,
read all of Chapters 2 and 3, Installation Procedures and Electrical
Installation. Make sure that all installation steps have been correctly
accomplished and all linkages are secured and properly attached.
Carefully review the direction of rotation for the actuator oil pump.

Manual 26580 UG-25+ Actuator
Woodward 13
Follow this procedure when putting a new or repaired UG-25+actuator into service.
1. Check that the actuator is full of the proper type and grade of clean oil (refer to the Oil Supply section
in this manual).
2. Properly adjust the linkage (refer to the Control Linkage section in this manual).
To prevent possible serious injury or loss of life, or damage to the
engine, be sure to allow sufficient overtravel at each end of the
terminal shaft so the actuator can shut down the engine, and give
maximum fuel when required. Misadjusted linkage could prevent the
actuator from shutting down the engine.
3. Adjust the external control system to give a low Position Command signal to the UG-25+actuator to
achieve a low speed setting to give low engine speed at initial 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.
4. Follow the engine manufacturer's instructions, and start the engine.
5. Adjust the selected speed setting of the control system to bring the engine to rated speed.
6. Obtain system stability by adjusting the control system's dynamics. (If less than the recommended
actuator output stroke is used, it may cause for less than optimum engine stability or response.)
All operating adjustments of the UG-25+actuator are made during factory calibration. Additional
adjustment should not be needed.
Unpacking
Be careful when unpacking the unit. Check the unit for signs of damage, such as bent or dented panels,
scratches, and loose or broken parts. Notify the shipper and Woodward if damage is found.
Receiving
After factory testing and calibration, the UG-25+actuator is drained of oil. This leaves a light film of oil on
internal parts to prevent rust. External parts are painted or coated with a spray lubricant/rust inhibitor.
No internal cleaning or flushing is necessary before installation and operation. The little oil left in the
actuator is clean, multi-viscosity engine oil, which will not contaminate the oil selected to operate the
actuator.
Fill the actuator with 2.1 liters (2.2 quarts) of oil selected to match the expected operating conditions. (If
the actuator is a direct replacement for a UG governor, you may use the same grade and weight of oil
that was being used in the governor.) Use only new, clean oil in the actuator. Do not allow dirt or
contamination to enter the actuator while filling with operating oil. Do not use oil drained from the UG
governor.

Manual 26580 UG-25+ Actuator
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Figure 2-1. UG-25+Actuator Overview

Manual 26580 UG-25+ Actuator
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Storage
The UG-25+actuator may be stored for short periods of time (less than a year) as received from the factory.
For long-term storage (more than a year), storage in an environment with large temperature changes, humid
or corrosive atmosphere, etc., or if the actuator is installed on the engine for storage, fill the actuator with oil
and follow preservation packaging instructions in Woodward manual 25075, Commercial Preservation
Packaging for Storage of Mechanical-Hydraulic Controls.
Drive Shaft Rotation
The actuator drive-shaft rotation is one direction only. Rotation, as viewed from the top of the actuator,
must be the same as that of the engine drive when looking down on the mounting pad.
If the actuator oil pump is rotated in the wrong direction, no oil pressure will be generated in the actuator.
Be sure engine mounting-pad drive and actuator-drive rotation are
the same. Incorrect drive rotation will cause the actuator to become
inoperative, and may cause actuator damage.
Figure 2-2. Proper Drive Shaft Rotation
Use the following procedure to change the direction of rotation:
1. Remove the four pump-housing screws located on the bottom of the
UG-25+actuator.
2. Index the pump plate 180 degrees to align the arrow corresponding to the direction of rotation
selected with the reference notch in the base.
3. Replace the four screws, and torque the screws to 10.2 N·m (90 lb-in).
4. Make sure that the actuator drive shaft rotates freely.
Mounting Location
Locate the UG-25+actuator at a distance from sources of extreme radiant heat, such as exhaust
manifolds, turbochargers, or live steam lines. The ambient operating temperature range of the control is
(0 to 55) °C / (32 to 131) °F (maximum allowable actuator case temperature is 100 °C / 212 °F max). In
spark-ignited applications, make sure the UG-25+actuator is located away from the ignition coil, and that
harness wires are not routed next to the spark plug wires.

Manual 26580 UG-25+ Actuator
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As shown in the specifications, the UG-25+actuator has been designed for and validated to a given
accelerated life vibration test level at the mounting surface of the actuator. The user should be aware that
in any application, bracket design could significantly change the vibration levels at the actuator base.
Therefore, every effort should be made to ensure the bracket is as stiff as possible so that engine
vibrations are not unduly amplified, creating an even more severe environment at the actuator.
Attitude
The UG-25+actuator can be installed in a vertical or near vertical position without affecting its calibration.
Do not install more than 45 degrees from vertical. See the outline drawing for installation instructions and
dimensions.
Mounting Dimension
When using the O-ring to seal between the UG-25+actuator and actuator mounting pad on the engine,
the mounting hole should have dimensions of (82.7 to 83.2) mm / (3.255 to 3.275) inches in order to
provide the correct amount of squeeze on the o-ring. The mounting hole must be concentric with the drive
in order to avoid side-loading the UG-25+actuator drive shaft. (This O-ring part number 1355-308 can be
ordered separately from Woodward.)
Lifting Method
When mounting the UG-25+on the engine, a lifting sling can be used as shown in the photo below.
This lifting method should be used only for normal installation of the
UG-25+. Do NOT use this method for removing the UG-25+if the
governor may be stuck in/on the engine drive. This could result in
serious damage to the UG-25
+
.

Manual 26580 UG-25+ Actuator
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Drive Connection
Make sure the UG-25+actuator drive shaft turns freely before installing the actuator. The drive gear or
coupling must slip freely into the actuator drive of the engine.
In case of a keyed drive shaft, torque the nut that secures the drive gear to
(34 to 41) Nm / (25 to 30) lb-ft maximum.
Do not apply external force. The drive must be free of binding, side load, or excess endplay. Improper
alignment or fit between the parts can result in excessive wear or actuator-drive seizure.
Mount the UG-25+actuator squarely on the mounting pad. Torque the mounting bolts evenly. There can
be no movement or rocking of the actuator on the engine-mounting pad.
Control Linkage
The terminal shaft has a travel of 42 degrees. Use 2/3 of the total rotation between no load and full load.
The additional “overtravel” should be split and used at both ends to provide maximum fuel when required
and to assure shutdown at minimum-fuel actuator position (see Figure 2-2).
To prevent possible serious injury or loss of life, or damage to the
engine, be sure to allow sufficient overtravel at each end of the
terminal shaft so the actuator can shut down the engine, and also
give maximum fuel when required. Misadjusted linkage could prevent
the actuator from shutting down the engine.

Manual 26580 UG-25+ Actuator
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Many control problems are related to the linkage between the actuator and the engine. Use only high-quality
rod-ends for the linkage which will last under the nearly constant motion associated with precise speed
control. The linkage must be stiff, not subject to engine-caused vibration. The linkage must be as light as
possible and still maintain the attributes of stiffness. Linkage which is too heavy can damage the actuator as
well as make it difficult to achieve steady control.
Installed linkages must operate smoothly, be free of binding, and free of lost motion due to worn parts. If
there is a collapsible member in the linkage, be sure it does not yield each time the actuator moves the
linkage rapidly.
Figure 2-3. Terminal Shaft Travel