Woodward VariStroke-I User manual

Product Manual 26727
(Revision R, 1/2020)
Original Instructions
VariStroke-I (VS-I)
Electro-hydraulic Actuator
Installation and Operation Manual
Released

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 publicatio
n 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 Out-of-date translations are marked with .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 26727
Copyright © Woodward, Inc. 2013 - 2020
All Rights Reserved
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Contents
W ARNINGS AND N OTICES ..............................................................................................................6
E LECTROSTATIC D ISCHARGE A WARENESS ....................................................................................7
R EGULATORY C OMPLIANCE ..........................................................................................................8
C HAPTER 1. G ENERAL I NFORMATION ...........................................................................................12
Introduction.................................................................................................................................................. 12
VS-I Integrated and Remote Construction .................................................................................................. 14
VS-I Remote Servo Only Construction ....................................................................................................... 18
C HAPTER 2. S PECIFICATIONS ......................................................................................................21
Physical and Performance Specifications................................................................................................... 21
Special Ambient Temperature Specifications / Allowances........................................................................ 25
Performance Index...................................................................................................................................... 26
Diagrams ..................................................................................................................................................... 27
C HAPTER 3. I NSTALLATION .........................................................................................................33
Receiving Instructions ................................................................................................................................. 33
Unpacking Instructions................................................................................................................................ 33
Installation Instructions................................................................................................................................ 34
C HAPTER 4. S ERVICE T OOL I NSTALLATION ..................................................................................57
System Requirements................................................................................................................................. 57
Setup ........................................................................................................................................................... 57
Installing the VariStroke-I Service Tool....................................................................................................... 58
Connecting to the VariStroke-I.................................................................................................................... 62
C HAPTER 5. C ALIBRATION AND M ONITORING ...............................................................................63
Introduction.................................................................................................................................................. 63
System Information ..................................................................................................................................... 63
System Information Page............................................................................................................................ 65
Configuration and Calibration ..................................................................................................................... 66
Cylinder Configuration................................................................................................................................. 67
Manual Operation........................................................................................................................................ 7 3
C HAPTER 6. C ONFIGURATION ......................................................................................................74
Input Configuration...................................................................................................................................... 74
Output Configuration ................................................................................................................................... 76
Advanced Configuration.............................................................................................................................. 78
Linearization................................................................................................................................................ 79
Alarms/Shutdown ........................................................................................................................................ 79
Saving and Loading Settings ...................................................................................................................... 82
C HAPTER 7. R EPAIR AND T ROUBLESHOOTING ..............................................................................83
General........................................................................................................................................................ 83
Shaft Seal Replacement ............................................................................................................................. 83
Servo Valve / Hydraulic Cylinder Replacement .......................................................................................... 85
Troubleshooting .......................................................................................................................................... 85
Maintenance................................................................................................................................................ 91
C HAPTER 8. P RODUCT S UPPORT AND S ERVICE O PTIONS .............................................................92
Product Support Options............................................................................................................................. 92
Product Service Options ............................................................................................................................. 92
Returning Equipment for Repair ................................................................................................................. 93
Replacement Parts...................................................................................................................................... 94
Engineering Services .................................................................................................................................. 94
Contacting Woodward’s Support Organization........................................................................................... 94
Technical Assistance .................................................................................................................................. 95
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C HAPTER 9. A SSET M ANAGEMENT AND R EFURBISHMENT S CHEDULING P ERIOD ............................96
C HAPTER 10. L ONG -T ERM S TORAGE R EQUIREMENTS ..................................................................97
A PPENDICES O UTLINE D RAWINGS AND I NSTALLATION F EATURES .................................................98
Appendix A – V45 Servo, 4-inch (100mm) Bore Integrated Servo-Cylinder (V45TD-10XX)...................... 99
Appendix B – V45 Servo, 5-inch (127mm) Bore Integrated Servo-Cylinder (V45TD-12XX).................... 101
Appendix C – V45 Servo, 6-inch (150mm) Bore Integrated Servo-Cylinder (V45TD-15XX).................... 103
Appendix D – V45 Servo, 8-inch (200mm) Bore Integrated Servo-Cylinder (V45TD-20XX).................... 105
Appendix E – V45 Servo, 10-inch (250mm) Bore Integrated Servo-Cylinder (V45TD-25XX).................. 1 0 7
Appendix F – V45 Servo, 4-inch (100mm) Bore Remote Servo-Cylinder (V45RD-10XX) ....................... 109
Appendix G – V45 Servo, 5-inch (127mm) Bore Remote Servo-Cylinder (V45RD-12XX)....................... 112
Appendix H – V45 Servo, 6-inch (150mm) Bore Remote Servo-Cylinder (V45RD-15XX) ....................... 115
Appendix I – V45 Servo, 8-inch (200mm) Bore Remote Servo-Cylinder (V45RD-20XX) ........................ 118
Appendix J – V45 Servo, 10-inch (250mm) Bore Remote Servo-Cylinder (V45RD-25XX)...................... 121
Appendix K – V45 Servo, 4-inch (100mm) Bore Integrated Spring Assist Servo-Cylinder (V45TX-
1010) ......................................................................................................................................................... 124
Appendix L – V45 Servo, 6-inch (150mm) Bore Integrated Spring Assist Servo-Cylinder (V45TX-
15XX) ........................................................................................................................................................ 126
Appendix M – V45 Servo, 8-inch (200mm) Bore Integrated Spring Assist Servo-Cylinder (V45TX-
20XX) ........................................................................................................................................................ 128
Appendix N – V45 Servo, 10-inch (250mm) Bore Integrated Spring Assist Servo-Cylinder (V45TX-
2510) ......................................................................................................................................................... 130
Appendix O – V45 Servo, 4-inch (100mm) Bore Remote Spring Assist Servo-Cylinder (V45RX-1010).. 132
Appendix P – V45 Servo, 6-inch (150mm) Bore Remote Spring Assist Servo-Cylinder (V45RX-15XX) . 135
Appendix Q – V45 Servo, 8-inch (200mm) Bore Remote Spring Assist Servo-Cylinder (V45RX-20XX). 138
Appendix R – V45 Servo, 10-inch (250mm) Bore Remote Spring Assist Servo-Cylinder (V45RX-2510) 141
Appendix S – Remote Servo Version (V45V) ........................................................................................... 144
R EVISION H ISTORY ...................................................................................................................146
D ECLARATIONS ........................................................................................................................148
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Illustrations and Tables
Figure 1-1. VariStroke-I, Key Features ....................................................................................................... 14
Figure 1-2. VariStroke-I Remote, Key Features.......................................................................................... 15
Figure 1-3. Hydraulic Power Cylinder - Stroke Adjustment Options........................................................... 16
Figure 1-4. Application Example ................................................................................................................. 17
Figure 1-5. VariStroke-I Remote Servo, Key Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............................. 19
Figure 1-6. Nomenclature and Ordering Number Encoder......................................................................... 20
Figure 2-1. VSI Maximum Transient Flow Rates (During Full Slew) .......................................................... 24
Figure 2-2. Steady State Flow Rate............................................................................................................ 25
Figure 2-3. Performance Chart for 4”, 5”, and 6” Bore Actuators ............................................................... 27
Figure 2-4. Basic Device Block Diagram without Trip Function.................................................................. 27
Figure 2-5. VS-I Integrated Hydraulic Schematic ....................................................................................... 28
Figure 2-6. VS-I Remote Hydraulic Schematic ........................................................................................... 28
Figure 2-7. VS-I Remote Servo Hydraulic Schematic................................................................................. 29
Figure 2-8. VS-I Spring Assist Integrated Hydraulic Schematic ................................................................. 29
Figure 2-9. VS-I Spring Assist Remote Hydraulic Schematic..................................................................... 30
Figure 3-1a. VS-I Integrated Product Installation Interface - Bolting Pattern and Installation Features ..... 34
Figure 3-1b. VS-I Integrated Product Installation Interface - Bolting Pattern and Installation Features ..... 35
Figure 3-2a. VS-I Remote. Product Installation Interface - Bolting Pattern and Installation Features........ 36
Figure 3-2b. VS-I Remote. Product Installation Interface—Bolting Pattern and Installation Features ....... 37
Figure 3-2c. Hydraulic Rod position for different cylinders versions........................................................... 38
Figure 3-3. VS-I Remote Servo. Product Installation Interface - Bolting Pattern........................................ 39
Figure 3-4. VS-I Lifting Positions ................................................................................................................ 40
Figure 3-5. Incorrect Lifting Method ............................................................................................................ 41
Figure 3-6. Suggested Configuration .......................................................................................................... 43
Figure 3-7. Electrical Wiring Diagram ......................................................................................................... 45
Figure 3-8. Power Supply Input Connections ............................................................................................. 46
Figure 3-9. Correct Wiring to Power Supply Input ...................................................................................... 47
Figure 3-10. Example of Incorrect Wiring to Power Supply Input ............................................................... 47
Figure 3-11. Recommended Wiring Strain Relief ....................................................................................... 48
Figure 3-12. Analog Input Connections ...................................................................................................... 49
Figure 3-13. Final Cylinder Position Feedback Analog Input Connections ................................................ 50
Figure 3-14. Cylinder Position Sensor Wiring Diagram When Using Vs-1 Internal Power......................... 50
Figure 3-15. Cylinder Position Sensor Wiring Diagram When Using External Power Supply.................... 51
Figure 3-16. Example of Incorrect Cylinder Position Sensor Connection When Using External Power
Supply .................................................................................................................................... 51
Figure 3-17. Cylinder Position Connectors ................................................................................................. 51
Figure 3-18. Cylinder Position Sensor Connection Scheme with MTS Sensor .......................................... 51
Figure 3-19. Analog Output Connection ..................................................................................................... 52
Figure 3-20. Discrete Inputs Connections................................................................................................... 53
Figure 3-21. Discrete Output Connections.................................................................................................. 54
Figure 3-22. CAN Ports Connections.......................................................................................................... 55
Figure 4-1. Service Port Connections ......................................................................................................... 58
Figure 4-2. Service Tool Welcome Screen ................................................................................................. 59
Figure 4-3. End-User License Agreement Screen...................................................................................... 59
Figure 4-4. Service Tool Installation Screen............................................................................................... 60
Figure 4-5. Service Tool Installation Progress Screen ............................................................................... 60
Figure 4-6. Installation Complete and Finish Screen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................................ 61
Figure 4-7. VS 1 Service Tool Home Screen.............................................................................................. 62
Figure 5-1. System Information and Status Overview Scree...................................................................... 63
Figure 5-2. System Information Page ......................................................................................................... 65
Figure 5-3. Configuration/Calibration Page................................................................................................. 66
Figure 5-4. Service Tool Calibration Screen ............................................................................................... 69
Figure 5-5. Calibration Find Minimum Stop Screen.................................................................................... 70
Figure 5-6. Calibration in Progress Screen................................................................................................. 71
Figure 5-7. Calibration Complete Screen.................................................................................................... 72
Figure 5-8. Manual Operation Screen......................................................................................................... 73
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Figure 6-1. Input Configuration Screen....................................................................................................... 74
Figure 6-2. Output Configuration Screen .................................................................................................... 76
Figure 6-3. Advanced Configuration Screen............................................................................................... 78
Figure 6-4. Linearization Screen................................................................................................................. 79
Figure 6-5. Alarms and Shutdowns Screen ................................................................................................ 80
Figure 6-6. Alarms and Shutdowns Configuration Screen.......................................................................... 81
Figure 6-7. Settings Menu........................................................................................................................... 82
Figure 7-1. Shaft Seals Replacement Kits and Installation......................................................................... 84
Figure A-1a. V45TD-10XX Integrated Installation Dimensions................................................................... 99
Figure A-1b. V45TD-10XX Integrated Installation Dimensions................................................................. 100
Figure B-1a. V45TD-12XX Integrated Installation Dimensions................................................................. 101
Figure B-1b. V45TD-12XX Integrated Installation Dimensions................................................................. 102
Figure C-1a. V45TD-15XX Integrated Installation Dimensions ................................................................ 103
Figure C-1b. V45TD-15XX Integrated Installation Dimensions ................................................................ 104
Figure D-1a. V45TD-20XX Integrated Installation Dimensions ................................................................ 105
Figure D-1b. V45TD-20XX Integrated Installation Dimensions ................................................................ 106
Figure E-1a. V45TD-25XX Integrated Installation Dimensions................................................................. 107
Figure E-1b. V45TD-25XX Integrated Installation Dimensions................................................................. 108
Figure F-1a. VS-I Remote Maximum Allowable Distance between Actuator and Servo .......................... 109
Figure F-1b. V45RD-10XX Remote Installation Dimensions .................................................................... 110
Figure F-1c. V45RD-10XX Remote Installation Dimensions .................................................................... 111
Figure G-1a. VS-I Remote Maximum Allowable Distance between Actuator and Servo ......................... 112
Figure G-1b. V45RD-12XX Remote Installation Dimensions ................................................................... 113
Figure G-1c. V45RD-12XX Remote Installation Dimensions.................................................................... 114
Figure H-1a. VS-I Remote Maximum Allowable Distance Between Actuator and Servo ......................... 115
Figure H-1b. V45RD-15XX Remote Installation Dimensions.................................................................... 116
Figure H-1c. V45RD-15XX Remote Installation Dimensions.................................................................... 117
Figure I-1a. VS-I Remote Maximum Allowable Distance between Actuator and Servo ........................... 118
Figure I-1b. V45RD-20XX Remote Installation Dimensions ..................................................................... 119
Figure I-1c. V45RD-20XX Remote Installation Dimensions ..................................................................... 120
Figure J-1a. VS-I Remote Maximum Allowable Distance Between Actuator and Servo .......................... 121
Figure J-1b. V45RD-25XX Remote Installation Dimensions .................................................................... 122
Figure J-1c. V45RD-25XX Remote Installation Dimensions..................................................................... 123
Figure K-1a. V45TX-1010 Integrated Spring Assist Installation Dimensions ........................................... 124
Figure K-1b. V45TX-1010 Integrated Spring Assist Installation Dimensions ........................................... 125
Figure L-1a. V45TX-15XX Integrated Spring Assist Installation Dimensions ........................................... 126
Figure L-1b. V45TX-15XX Integrated Spring Assist Installation Dimensions ........................................... 127
Figure M-1a. V45TX-20XX Integrated Spring Assist Installation Dimensions .......................................... 128
Figure M-1b. V45TX-20XX Integrated Spring Assist Installation Dimensions .......................................... 129
Figure N-1a. V45TX-2510 Integrated Spring Assist Installation Dimensions ........................................... 130
Figure N-1b. V45TX-2510 Integrated Spring Assist Installation Dimensions ........................................... 131
Figure O-1a. VS-I Remote Maximum Allowable Distance between Actuator and Servo ......................... 132
Figure O-1b. V45RX-1010 Remote Spring Assist Installation Dimensions .............................................. 133
Figure O-1c. V45RX-1010 Remote Spring Assist Installation Dimensions .............................................. 134
Figure P-1a. VS-I Remote Maximum Allowable Distance Between Actuator and Servo ......................... 135
Figure P-1b. V45RX-15XX Remote Spring Assist Installation Dimensions.............................................. 136
Figure P-1c. V45RX-15XX Remote Spring Assist Installation Dimensions .............................................. 137
Figure Q-1a. VS-I Remote Maximum Allowable Distance between Actuator and Servo ......................... 138
Figure Q-1b. V45RX-20XX Remote Spring Assist Installation Dimensions ............................................. 139
Figure Q-1c. V45RX-20XX Remote Spring Assist Installation Dimensions.............................................. 140
Figure R-1a. VS-I Remote Maximum Allowable Distance between Actuator and Servo ......................... 141
Figure R-1b. V45RX-2510 Remote Spring Assist Installation Dimensions .............................................. 142
Figure R-1c. V45RX-2510 Remote Spring Assist Installation Dimensions............................................... 143
Figure S-1a. Typical VS-I Remote Servo Installation Dimensions............................................................ 144
Figure S-1b. Typical VS-I Remote Servo Installation Dimensions............................................................ 145
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Table RC-1. Linear Electro-Hydraulic Actuator, Model VariStroke-I........................................................... 10
Table 2-1. Bore and Rod Diameter by Valve Size ...................................................................................... 21
Table 2-2. Available Springs for Spring Assist Cylinders............................................................................ 21
Table 2-3. Environmental Specifications..................................................................................................... 22
Table 2-4. Electrical Specifications ............................................................................................................. 22
Table 2-5. Cylinder Position Sensor Requirements (Remote Servo Only)................................................. 23
Table 2-6. Hydraulic Specifications............................................................................................................. 23
Table 2-7. Special Ambient Temperature Specifications/Allowances ........................................................ 25
Table 2-8. VS-I Installation Drawings.......................................................................................................... 31
Table 3-1. VS-I Installation Bolts and Bolting Torques Recommendation.................................................. 37
Table 3-2. Recommended Fuse Ratings or Circuit Breakers. .................................................................... 46
Table 3-3. Terminal Assignment for this Option Usage. ............................................................................. 46
Table 7-1. VS-I General Troubleshooting Guide ........................................................................................ 85
Table 7-2. VS-I Demand Faults Guide........................................................................................................ 87
Table 7-3. VS-I Power Supply Faults.......................................................................................................... 88
Table 7-4. VS-I Feedback Faults ................................................................................................................ 88
Table 7-5. VS-I Temperature Faults ........................................................................................................... 89
Table 7-6. Performance Faults ................................................................................................................... 90
Table 7-6. Performance Faults (continued) ................................................................................................ 91
Table 7-7. Internal Faults ............................................................................................................................ 91
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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.
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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:
•DonottouchanypartofthePCBexcepttheedges.
•Donottouchtheelectricalconductors,theconnectors, or the components with conductive
devices or with your hands.
•WhenreplacingaPCB,keepthenewPCBintheplastic 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
Product Compliance Code: Product certifications are dictated by the product model number, and
traceable per the product serial number. For information on which hazardous locations any particular
VariStroke is rated for, refer to the Model Number and Model Number information below. Find the Model
Number on the nameplate of the VariStroke.
European Compliance for CE Marking:
These listings are limited only to those units bearing the CE Marking. Review the
Compliance Code table for more information.
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)
ATEX
D
irective:
Directive 2014/34/EU on the harmonisation of the laws of the Member
States relating to equipment and protective systems intended for use in
potentially explosive atmospheres
Zone 1: II 2 G Ex db IIB T4 Gb, Sira 14ATEX1028X
Zone 2: II 3 G Ex nA IIC T4 Gc, Sira 14ATEX5029X
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Other European
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 ISO 80079-36:2016 for Zone 1
installation.
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.
RoHS Directive:
Restriction of Hazardous Substances 2011/65/EU:
Woodward Turbomachinery Systems products are intended exclusively for
sale and use only as a part of Large Scale Fixed Installations per the
meaning of Art.2.4(e) of directive 2011/65/EU. This fulfills the requirements
stated in Art.2.4(c) and as such the product is excluded from the scope of
RoHS2.
EAC Customs Union
These listings are limited only to those units with labels, marking, and manuals in Russian language to
comply with their certificates and declaration. Review the Compliance Code table for more information.
EAC
Customs Union
(Marked):
Certified to Technical Regulation CU 012/2011 for use in potentially
explosive atmospheres per Certificate
RU C-US.MЮ62.B00436
Zone 1: 1Ex d IIB T4 Gb X
Zone 2: 2Ex nA IIC T4 Gc X
Other International Compliance
These listings are limited only to those units bearing the appropriate marking. Review the Compliance
Code table for more information.
IECEx
:
Certified for use in explosive atmospheres per Certificate:
IECEx CSA 13.0041X
Zone 1: Ex db IIB T4 Gb
Zone 2: Ex nA IIC T4 Gc
CCOE (PESO)
India:
Certified for explosive atmospheres under Petroleum Rules 2002. Zone 1
and Zone 2 per the IECEx certificate above.
TIIS Japan:
Code T – Integrated models are certified for use in explosive atmospheres
per TIIS Certificate TC21468. Zone 1 and Zone 2 per the IECEx certificate
above.
KCs Mark
Korea
KTL Certified for use in explosive atmospheres.
Zone 1, KTL 17-KA4BO-0458X as Ex db IIB T4 Gb
Zone 2, KTL 17-KA4BO-0459X as Ex nA IIC T4 Gb
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North American Compliance:
These listings are limited only to those units bearing the appropriate marking. Review the Compliance
Code table for more information.
CSA:
Certified for Class I, Div.1 Groups C, D T4 or Class I, Div. 2 Groups A, B, C,
D T4. For Use in Canada and the United States. Certificate 2669905.
Special Conditions for Safe Use
Wiring must be in accordance with North American, European, or other International wiring methods as
applicable, and in accordance with the authority having jurisdiction.
For Zone 1 or Division 1: Conduit seals must be installed within 18 inches (457 mm) of the conduit entry.
Field wiring must be suitable for at least +85 °C and 10 °C above the maximum fluid and ambient
temperatures.
The maximum hydraulic oil temperature is 70 °C continuous.
The following have a maximum constructional gap (ic) less than that required by Tables 1 and 2 of EN
60079-1 and hence are as detailed below:
Table RC-1. Linear Electro-Hydraulic Actuator, Model VariStroke-I
Flame Path
Max Gap, ic (mm)
Comment
Min. width of joint L
(mm) Comment
Spool to Spacer 0.079 13.46
Sleeve to Spacer 0.079 12.85
Sleeve to Sleeve 0.048 14.76
Sleeve to Housing 0.076 15.85
Sensor to Plate 0.08 36.25
Plate to Housing 0.10 22.91
Plate to Housing 0.10 20.22
Plate to Plate 0.10 22.91
Connect external safety ground terminal to earth ground.
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.
Under certain extreme circumstances, the non-metallic parts incorporated in the enclosure of this
equipment may generate an ignition-capable level of electrostatic charge. Therefore, do not install the
equipment in a location where the external conditions are conducive to the build-up of electrostatic charge
on such surfaces. Proper grounding when used in a fixed installation mitigates this risk. In addition, only
clean the equipment with a damp cloth.
Transient protection for the VariStroke-I is to be provided externally by the end user. The transient
protection device is to be set at a level not exceeding 140% of the peak rated voltage.
The installation of the VariStroke-I shall only be within a Pollution Degree 2 environment as defined in IEC
60664-1.
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EXPLOSION HAZARD—Do not remove covers or connect/disconnect
electrical circuits 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 applications.
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, applications
Division 2 ou Zone 2.
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
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Chapter 1.
General Information
Introduction
The VariStroke-I is a linear electro-hydraulic actuator that utilizes a double-acting or spring-assist power
cylinder with integrated electronic driver module, servo valve, and redundant MLDTs (Magnetostrictive
Linear Displacement Transducer) – based position feedback sensors to precisely control steam turbine
valves. The actuator’s driver module accepts one or two (redundant) 4–20 mA demand setpoints and
compares these setpoints to the sensed actuator shaft position to accurately control output shaft position.
The actuator’s output shaft position is controlled by a digital controller with an internal rotary servo valve
that ports supply oil to and from its power cylinder piston. This actuator’s digital controller architecture
allows it to perform stable position control during normal conditions, and responds quickly to desired valve
step changes during system or plant transients. The actuator output force is generated only by oil
pressure for double-acting power cylinder. For the spring assist, actuator output force is a combination of
force from hydraulic pressure and spring. Spring assist cylinder is still working as double acting actuator
but it has a spring installed inside the cylinder. Spring can be mounted either on the piston or rod side and
it generates force toward the failsafe position. There are three different spring force categories for each
cylinder diameter, except for 8” and 10” cylinder bores which need four spring force categories to cover
application needs. The springs are rated at about ~1.5%, ~2.5%, ~5.5%, and ~10.5% of stall force at 500-
psi supply pressure.
As a means of protecting the turbine, an internal servo valve-return spring forces the actuator to a failsafe
position to safely close turbine control valves upon any internal unit failure (electrical input power failure,
position sensor failure, processor failure, etc.). Additionally for the spring assist, power cylinder the
actuator spring assists in closing the valve in the event of the loss of oil pressure and helps to maintain
fail safe position.
The VariStroke-I actuator is a product family with many different models available for purchase depending
on the force, stroke, and redundancy required. Servo V45 (flow 212-530l/min) works with 4, 5, 6, 8 and 10
inch actuators. Cylinders are available with standard bore diameters and standard stroke ranges. The
VariStroke’s unique “variable stroke” capability also allows users to customize/set the actuator’s exact
maximum stop position in the field to meet their requirement. The VariStroke-I is available as an
integrated unit, or as a Remote Servo kit where the cylinder can be mounted up to 3 meters (approx.
10 feet) away from the servo. V45 servo is available also as Servo Only option for users who wish to use
their own hydraulic cylinder.
The VariStroke-I is factory and/or field configurable via a computer-based service tool. The actuator’s PCI
Service Tool uses a simple user-friendly format to allow users to easily configure, calibrate, and adjust all
internal functions and response settings. The VariStroke-I also includes a 4–20 mA output channel to
indicate output shaft (control valve) position, and unit alarm and shut down relay outputs for use as unit
health and status indications.
The total installed cost for this fully integrated actuator is low because it has been completely assembled
and tested at the factory. This greatly reduces OEM and end-user fabrication time, testing time, and site
assembly time.
The VariStroke Actuator offers the following benefits to the user in comparison to other electro-hydraulic
actuators:
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Dirt Tolerance
The VariStroke-I actuator is specifically designed for steam turbine applications where turbine lube oil is
also used to power the hydraulic turbine control valve actuator(s). Steam turbine applications can be
extremely challenging for hydraulic control valve actuators as dirt, metal shavings, water, and other
contaminants are common in such oil systems. Also due to the high temperatures at which steam
turbines operate, turbine oil breakdown is common, resulting in the creation of a sludge-type substance
and the varnishing of internal system components. However, the VariStroke-I actuator is designed to
operate reliably within such challenging applications. Its corrosion-resistant materials, single moving
rotary valve, 222 N (50 lbf) of chip shear force, and self-cleaning port design allow it to operate in such
applications without experiencing undesirable sticking or dragging.
Valve Rack Linearization
Since flow-through single and staged inlet steam valves tend to be non-linear throughout their flow range,
turbine controls must be de-tuned to compensate for instability or sluggish control points throughout this
range. As a way of allowing turbine control optimization, the VariStroke-I includes an 11-point linearization
table to allow turbine OEMs or users to compensate for poor valve linearization by digitally linearizing the
control-to-valve flow relationship.
Side Load Capability
A common problem with turbine actuators is oil leaking from their output shaft due to connection to valve
rack linkages, which have an arc-type of motion. This motion results in side loading of the actuator shaft,
and after long periods may result in shaft-seal wear and resultant oil leakage. Designed for a continuous
side load of up to 10% of actuator output, the VariStroke-I actuator incorporates a high-force precision
bearing and triple-seal technology on its output shaft to solve this typical application problem.
Chemically Resistant Versions
For steam turbine applications where lube oil contains harsh chemical contaminants (ammonia, hydrogen
sulfide etc.), a chemically resistant version of the VariStroke has been developed. Chemically resistant
versions feature best in class seals in all wetted locations of the servo actuator and cylinder. Chemically
resistant versions provide an optimal solution for extreme chemical resistance while still maintaining
VariStroke operating pressure and temperature ranges. Please contact Woodward for available models
and information regarding chemical resistance for specific applications.
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VS-I Integrated and Remote Construction
The VariStroke-I is made up of the following major components (Figure 1-1):
1. Hydraulic Power Cylinder
2. Rotary Servo Valve
3. Feedback Sensors: MLDT (Magnetostrictive Linear Displacement Transducer) – for power cylinder
position controlling
4. Integrated electronic driver module (PCB)
Figure 1-1. VariStroke-I, Key Features
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The VariStroke-I Remote Servo Kit (Figure 1-2) contains the same primary components as integrated
version, this kit allows the Hydraulic Power Cylinder to be mounted separately from the servo in
applications where space is constrained.
Figure 1-2. VariStroke-I Remote, Key Features
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Hydraulic Power Cylinder
The simple and robust design of VS-I hydraulic cylinder (Figure 1-3) is capable of consistent performance
for extended periods in challenging environments. Hydraulic cylinder is designed to operate in wide range
of hydraulic pressures and with high oil contamination. The actuation stroke range can be adjusted
precisely using PC service tool allowing the same actuator to accommodate a variety of strokes.
The hydraulic power cylinder is designed to be field replaceable in turbine shut down condition.
Figure 1-3. Hydraulic Power Cylinder - Stroke Adjustment Options
Rotary Servo Valve
The servo valve has four ports: Supply, two Control Ports, and Drain/Tank. With the hydraulic valve in its
middle position, all ports are blocked. As the valve rotates, the supply is connected to a control port while
simultaneously connecting the drain to the other control port. The combined action of the servo position
controller and cylinder position controller modulate the power cylinder position as necessary to match the
input demand.
Additionally, the Remote Servo has an OVBD (Over Board Drain) port which is permanently connected to
drain. This port can (optionally) be connected to the OVBD connection on Hydraulic Power Cylinder to
drain any leakage pass the primary rod seal.
A unique function of the software is a periodic, symmetrically opposed impulse which flushes silt and
debris from the servo valve without causing undue wear called “Silt Buster”. At the interval and amplitude
selected by the user, this function provides a very rapid motion of the hydraulic valve allowing any silt to
be flushed to the drain passage. This motion is followed immediately by a step of equal amplitude in the
opposite direction. The opposing symmetry of the impulse results in no net change in fluid volume to the
controlled servo valve, and thus does not interrupt the control of the turbine. This unique function provides
a higher degree of stability, reliability, and silt resistance.
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If the unit detects any diagnostic shut down condition, or if the detected diagnostic condition prevents
reliable control, or if a loss of power occurs, the servo valve return spring forces the valve to connect the
appropriate control pressure to drain causing the cylinder to move to the fail-safe position.
Servo Valve Actuator
The VS-I uses a rotary limited angle torque (LAT) actuator. The permanent magnet rotor is directly
coupled to the servo valve.
The position of the rotor is measured by a solid state integrated circuit on the PCB which detects the
orientation of the sensing magnet on the shaft. The
H-bridge drive is regulated by the microprocessor to precisely control the servo valve position and
maintain the cylinder stroke position demand.
Electronic Driver Module Printed Circuit Board (PCB)
The PCB is mounted on top of the housing and performs the following tasks:
•PowerSupply
•IsolatedInputandOutputs
•DualRedundantDemandinputs
•DualRedundantinputsforFinalCylinderFeedback
•Microprocessorbasedcontrol
•ActuatorH-BridgeDrive
•CurrentLimitingforThermalProtection
•AdvancedDiagnostics
•DiscreteOutputsforFault,AlarmandShutdownEnunciation
Figure 1-4. Application Example
The shield connections for the Analog Output (terminal #20), CAN1 (terminal #23) and CAN2 (terminal
#29) are through capacitors only as indicated in the wiring section of this manual.
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The power supply system performs the EMI filtering on the (18 to 32) V (dc) input voltage, generates
controlled voltages for several electronics sub-systems and is monitored for proper operation. If input
voltage or internal power systems are detected outside of allowable operating ranges, a diagnostic alarm
will be enunciated.
Calibration and configuration of alarms and shut down and redundancy operation are configurable via the
PC Service Tool.
The primary demand and redundant demand / feedback input signals are designed for a (4 to 20) mA
control signal. Each input signal is EMC protected.
Discrete outputs are provided for alarm and shut down enunciation. An internal LED also is illuminated
when a fault condition is detected. Cover needs to be removed to see this LED. The configurable discrete
output can be customized to output a variety of enunciations using the PC Service Tool. All of the discrete
outputs are configurable for normally open or normally closed action using the PC Service Tool.
Cylinder Position Control
The cylinder position controller adjusts the hydraulic power cylinder position to match the feedback signal
to the demand. Monitoring of both the servo position controller and cylinder position controller ensures
accurate tracking.
The position controller regulates a Pulse Width Modulated (PWM) drive signal to the actuator. The drive
current to the actuator is regulated, transiently allowing up to 10 Amps to be provided to move the
actuator at its maximum speed and torque. A steady state current limit becomes active after a period of a
few seconds to protect the actuator and electronics.
VS-I Remote Servo Only Construction
The Remote Servo (Figure 1-5) has the following major components:
1. Rotary Servo Valve
2. PCB (This information is available in the VS-I Integrated and Remote Construction section above
Rotary Servo Valve
The hydraulic servo valve has five ports: Supply, two Control Ports, Over Board Drain (OVBD), and
Drain/Tank. With the hydraulic valve in its middle position, both control ports are blocked. As the valve
rotates, supply pressure is connected to a control port while simultaneously connecting the drain to the
other control port. The combined action of the servo position controller and cylinder position controller
modulate the power cylinder position as necessary to match the input demand. OVBD is permanently
connected to drain and can (optionally) be connected to the OVBD connection on Hydraulic Power
Cylinder to drain any leakage pass the primary rod seal.
A unique function of the software is a periodic, symmetrically opposed impulse (called "Silt Buster") which
flushes silt and debris from the servo valve without causing undue wear. At the interval and amplitude
selected by the user, this function provides a very rapid motion of the hydraulic valve, allowing any silt to
be flushed to the drain passage. This motion is followed immediately by a step of equal amplitude in the
opposite direction. The opposing symmetry of the impulse results in no net change in fluid volume to the
controlled servo valve, and thus does not interrupt the control of the turbine. This unique function provides
a higher degree of stability, reliability, and silt resistance.
If the unit detects any diagnostic shut down condition, or if the detected diagnostic condition prevents
reliable control, or if a loss of power occurs, the servo valve return spring forces the valve to connect the
appropriate control pressure to drain, causing the cylinder to move to the fail-safe position.
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