Omron NT20S-ST121B-EV3 User manual

Programmable Terminal
Cat. No. V091-E1-01
NT20
USER’S MANUAL

NT-series
Programmable Terminal
User’s Manual
Produced March 2007

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v
Notice:
OMRON products are manufactured for use according to proper procedures by a qualified operator
and only for the purposes described in this manual.
The following conventions are used to indicate and classify precautions in this manual. Always heed
the information provided with them. Failure to heed precautions can result in injury to people or dam-
age to property.
!DANGER Indicates an imminently hazardous situation which, if not avoided, will result in death or
serious injury. Additionally, there may be severe property damage.
!WARNING Indicates a potentially hazardous situation which, if not avoided, could result in death or
serious injury. Additionally, there may be severe property damage.
!Caution Indicates a potentially hazardous situation which, if not avoided, may result in minor or
moderate injury, or property damage.
OMRON Product References
All OMRON products are capitalized in this manual. The word “Unit” is also capitalized when it refers to
an OMRON product, regardless of whether or not it appears in the proper name of the product.
The abbreviation “Ch,” which appears in some displays and on some OMRON products, often means
“word” and is abbreviated “Wd” in documentation in this sense.
The abbreviation “PLC” means Programmable Controller. “PC” is used, however, in some Program-
ming Device displays to mean Programmable Controller.
The abbreviation “Host” means a PLC that controls the NT20.
Visual Aids
The following headings appear in the left column of the manual to help you locate different types of
information.
Note Indicates information of particular interest for efficient and convenient opera-
tion of the product.
1,2,3... 1. Indicates lists of one sort or another, such as procedures, checklists, etc.
OMRON, 2007
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form, o
r
by any means, mechanical, electronic, photocopying, recording, or otherwise, without the prior written permission o
f
OMRON.
No patent liability is assumed with respect to the use of the information contained herein. Moreover, because OMRON is con-
stantly striving to improve its high-quality products, the information contained in this manual is subject to change without
notice. Every precaution has been taken in the preparation of this manual. Nevertheless, OMRON assumes no responsibility
for errors or omissions. Neither is any liability assumed for damages resulting from the use of the information contained in
this publication.

vi

vii
TABLE OF CONTENTS
PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvii
1 Intended Audience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xviii
2 General Precautions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xviii
3 Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xviii
4 Operating Environment Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xix
5 Application Precautions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xix
6 EC Directives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xx
SECTION 1
Functions of the NT20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1-1 Role and Operation of NT20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1-2 Functions of NT20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1-3 Method for Connection to the Host . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1-4 Communications with PLC by Direct Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
1-5 Communications Using RS-232C (NT20-ST128) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
1-6 Before Operating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
SECTION 2
Hardware Settings and Connections. . . . . . . . . . . . . . . . . . . 17
2-1 Description of Parts and Settings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2-2 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
2-3 Connecting Link Adapters and RS-422A Converters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
2-4 Connecting the NT Support Tool. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
2-5 Using a Memory Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
2-6 Connecting to the RS-232C Port at the Host . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
2-7 Communicating with the PLC Using C200H Direct Communications. . . . . . . . . . . . . . . . . 73
2-8 Host Connections by RS-232C (NT20-ST128). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
SECTION 3
System Menu Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
3-1 Operation Flow by the System Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
3-2 Starting the NT20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
3-3 Operation Modes and the System Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
3-4 Initializing Memory. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
3-5 Setting the Conditions of Communications with the Host by Using the Memory Switches. 91
3-6 Registering the Screen Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .102
3-7 Starting the Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
3-8 Various System Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
3-9 System Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
3-10 Transferring the System Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
3-11 Transferring the Resource Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

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TABLE OF CONTENTS
SECTION 4
NT20 Functions and Operation . . . . . . . . . . . . . . . . . . . . . . . 133
4-1 Screen Creation Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .134
4-2 Outline of Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
4-3 Screen Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
4-4 Memory Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
4-5 Bar Graphs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
4-6 Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
4-7 Touch Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
4-8 Numeral Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
SECTION 5
How to Use the Host Link/NT Link . . . . . . . . . . . . . . . . . . . 165
5-1 Overview of Direct Connection Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166
5-2 Memory Tables and Bar Graphs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177
5-3 Lamps, Touch Switches, Numeral Setting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191
5-4 NT20 Status Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203
5-5 Notification of the Operating Status to the PLC
(Determining the NT20 Operating Status) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208
SECTION 6
Using RS-232C Communications . . . . . . . . . . . . . . . . . . . . . 211
6-1 Table of Commands. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212
6-2 RS-232C Communications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
6-3 Screen Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216
6-4 Memory Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218
6-5 Lamps, Touch Switches, Numeral Setting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221
6-6 Controlling the NT20 Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .227
6-7 Terminal Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229
6-8 Key to Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234
SECTION 7
Troubleshooting and Maintenance . . . . . . . . . . . . . . . . . . . . 247
7-1 Hardware Faults. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
7-2 Responding to Displayed Error Messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249
7-3 Maintenance of the NT20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253
7-4 Inspection and Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
Appendices
A Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255
B Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261
C Transporting and Storing PTs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263

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TABLE OF CONTENTS
D Making the Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265
E Making the Cable for Connecting a Personal Computer . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
F Model List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269
G Option List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277
H Special Characters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279
I Function Restrictions Depending on the Support Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281
Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283
Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287

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TABLE OF CONTENTS

xi
About this Manual:
This manual describes the basic functions and operation procedures of the NT-series programmable
terminal NT20, its operations when connected to a PLC or a Host, and includes the sections described
below.
Please read this manual carefully and be sure you understand the information provided before
attempting to install and operate the NT-series programmable terminal NT20.
!WARNING Failure to read and understand the information provided in this manual may result in
personal injury or death, damage to the product, or product failure. Please read each
section in its entirety and be sure you understand the information provided in the
section and related sections before attempting any of the procedures or operations
given.
Precautions provides general precautions for using the NT20 and related devices.
Section 1 describes the operation functions, system configuration, and the direct connection function
of the NT20.
Section 2 describes the NT20 hardware settings, its installation in an operation panel, its connection
to the Host, etc.
Section 3 describes the procedure before operating the NT20, and useful functions when operating it.
Also describes how to perform an operation check.
Section 4 describes the functions of the NT20 when it is connected to a Host.
Section 5 describes how to operate the NT20 when the host link/NT link is used for communications.
Section 6 describes how to operate the NT20 when the RS-232C interface is used for communica-
tions. Read this section only when using the NT20-ST128.
Section 7 describes the procedures to follow when the system does not operate correctly, and the pro-
cedure for routine maintenance of the NT20.
APPENDIX describes the specifications and the method for making connecting cables, and includes
an area list for the PLC.
!WARNING Failure to read and understand the information provided in this manual may result in per-
sonal injury or death, damage to the product, or product failure. Please read each section
in its entirety and be sure you understand the information provided in the section and
related sections before attempting any of the procedures or operations given.

xii
Related Manuals and Their Contents:
The related manuals are indicated below.
The @symbol at the end of the manual number is the revision history symbol.
Operating the Programmable Terminal and Communicating with the Host
• NT20 Programmable Terminal User’s Manual (V091)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - This manual
This user’s manual is the manual for the NT20 itself.
The NT20 is a unit which integrates a programmable terminal body and host interface unit. This user’s
manual describes the functions and handling of both the programmable terminal body and the host
interface function.
Creating and Transferring Screen Data
• NT Support Tool for Windows Ver.4@Operation Manual (V061-E1-@)
The screens displayed on the NT20 are created with the Support Tool and transferred to the NT20.
This manual describes how to create and transfer screen data. It also describes how to download a
system program to a PT using the System Installer.
Connection to Other Makers’ PLCs
• PLC Connection V042-E1-@
NT20-ST121-E can be connected to Mitsubishi A series PLCs. This manual describes how to make
the connection and how to make settings when connecting the PT to a Mitsubishi A series PLC.
In order to use the PT while connected to a PLC made by a manufacturer other than OMRON, the Ver.
2.3 Support Tool must be used.

xiii
Read and Understand this Manual
Please read and understand this manual before using the product. Please consult your OMRON
representative if you have any questions or comments.
Warranty and Limitations of Liability
WARRANTY
OMRON's exclusive warranty is that the products are free from defects in materials and workmanship for a
period of one year (or other period if specified) from date of sale by OMRON.
OMRON MAKES NO WARRANTY OR REPRESENTATION, EXPRESS OR IMPLIED, REGARDING NON-
INFRINGEMENT, MERCHANTABILITY, OR FITNESS FOR PARTICULAR PURPOSE OF THE
PRODUCTS. ANY BUYER OR USER ACKNOWLEDGES THAT THE BUYER OR USER ALONE HAS
DETERMINED THAT THE PRODUCTS WILL SUITABLY MEET THE REQUIREMENTS OF THEIR
INTENDED USE. OMRON DISCLAIMS ALL OTHER WARRANTIES, EXPRESS OR IMPLIED.
LIMITATIONS OF LIABILITY
OMRON SHALL NOT BE RESPONSIBLE FOR SPECIAL, INDIRECT, OR CONSEQUENTIAL DAMAGES,
LOSS OF PROFITS OR COMMERCIAL LOSS IN ANY WAY CONNECTED WITH THE PRODUCTS,
WHETHER SUCH CLAIM IS BASED ON CONTRACT, WARRANTY, NEGLIGENCE, OR STRICT
LIABILITY.
In no event shall the responsibility of OMRON for any act exceed the individual price of the product on which
liability is asserted.
IN NO EVENT SHALL OMRON BE RESPONSIBLE FOR WARRANTY, REPAIR, OR OTHER CLAIMS
REGARDING THE PRODUCTS UNLESS OMRON'S ANALYSIS CONFIRMS THAT THE PRODUCTS
WERE PROPERLY HANDLED, STORED, INSTALLED, AND MAINTAINED AND NOT SUBJECT TO
CONTAMINATION, ABUSE, MISUSE, OR INAPPROPRIATE MODIFICATION OR REPAIR.

xiv
Application Considerations
SUITABILITY FOR USE
OMRON shall not be responsible for conformity with any standards, codes, or regulations that apply to the
combination of products in the customer's application or use of the products.
At the customer's request, OMRON will provide applicable third party certification documents identifying
ratings and limitations of use that apply to the products. This information by itself is not sufficient for a
complete determination of the suitability of the products in combination with the end product, machine,
system, or other application or use.
The following are some examples of applications for which particular attention must be given. This is not
intended to be an exhaustive list of all possible uses of the products, nor is it intended to imply that the uses
listed may be suitable for the products:
• Outdoor use, uses involving potential chemical contamination or electrical interference, or conditions or
uses not described in this manual.
• Nuclear energy control systems, combustion systems, railroad systems, aviation systems, medical
equipment, amusement machines, vehicles, safety equipment, and installations subject to separate
industry or government regulations.
• Systems, machines, and equipment that could present a risk to life or property.
Please know and observe all prohibitions of use applicable to the products.
NEVER USE THE PRODUCTS FOR AN APPLICATION INVOLVING SERIOUS RISK TO LIFE OR
PROPERTY WITHOUT ENSURING THAT THE SYSTEM AS A WHOLE HAS BEEN DESIGNED TO
ADDRESS THE RISKS, AND THAT THE OMRON PRODUCTS ARE PROPERLY RATED AND INSTALLED
FOR THE INTENDED USE WITHIN THE OVERALL EQUIPMENT OR SYSTEM.
PROGRAMMABLE PRODUCTS
OMRON shall not be responsible for the user's programming of a programmable product, or any
consequence thereof.

xv
Disclaimers
CHANGE IN SPECIFICATIONS
Product specifications and accessories may be changed at any time based on improvements and other
reasons.
It is our practice to change model numbers when published ratings or features are changed, or when
significant construction changes are made. However, some specifications of the products may be changed
without any notice. When in doubt, special model numbers may be assigned to fix or establish key
specifications for your application on your request. Please consult with your OMRON representative at any
time to confirm actual specifications of purchased products.
DIMENSIONS AND WEIGHTS
Dimensions and weights are nominal and are not to be used for manufacturing purposes, even when
tolerances are shown.
PERFORMANCE DATA
Performance data given in this manual is provided as a guide for the user in determining suitability and does
not constitute a warranty. It may represent the result of OMRON's test conditions, and the users must
correlate it to actual application requirements. Actual performance is subject to the OMRON Warranty and
Limitations of Liability.
ERRORS AND OMISSIONS
The information in this manual has been carefully checked and is believed to be accurate; however, no
responsibility is assumed for clerical, typographical, or proofreading errors, or omissions.

xvi

xvii
PRECAUTIONS
This section provides general precautions for using the Programmable Terminal.
The information contained in this section is important for the safe and reliable application of the Programmable
Terminal. You must read this section and understand the information contained before attempting to set up or
operate a Programmable Terminal.
1 Intended Audience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xviii
2 General Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xviii
3 Safety Precautions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xviii
4 Operating Environment Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xix
5 Application Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xix
6 EC Directives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xx

xviii
Intended Audience 1
1 Intended Audience
This manual is intended for the following personnel, who must also have
knowledge of electrical systems (an electrical engineer or the equivalent).
• Personnel in charge of introducing FA systems into production facilities.
• Personnel in charge of installing FA systems.
• Personnel in charge of designing and connecting FA systems.
• Personnel in charge of managing FA systems and facilities.
2 General Precautions
• The user must operate the product according to the performance specifi-
cations described in the operation manuals.
• Before using the product under conditions which are not described in the
manual or applying the product to nuclear control systems, railroad sys-
tems, aviation systems, vehicles, combustion systems, medical equip-
ment, amusement machines, safety equipment, and other systems,
machines, and equipment that may have a serious influence on lives and
property if used improperly, consult your OMRON representative.
• Make sure that the ratings and performance characteristics of the product
are sufficient for the systems, machines, and equipment, and be sure to
provide the systems, machines, and equipment with double safety mech-
anisms.
• This manual provides information for using the Programmable Terminal.
Be sure to read this manual before attempting to use the software and
keep this manual close at hand for reference during operation.
!WARNING It is extremely important that Programmable Terminals and related devices be
used for the specified purpose and under the specified conditions, especially
in applications that can directly or indirectly affect human life. You must con-
sult with your OMRON representative before applying Programmable Termi-
nals to the abovementioned applications.
!WARNING Do not use the input functions of the PT, such as touch switches or function
keys, for applications where danger to human life or serious property damage
is possible or for emergency switch applications.
3 Safety Precautions
Read these safety precautions carefully and make sure you understand them
before using the Programmable Terminal so that you can use it safely and cor-
rectly.
!WARNING Do not attempt to take the PLC apart and do not touch any internal parts while
the power is being supplied. Doing either of these may result in electrical
shock.
!Caution Carefully check the wiring before turning ON the power.
!Caution Do not connect AC power to the DC terminals. Incorrect wiring may result in
burning.

xix
Operating Environment Precautions 4
!Caution If the DIP switch settings have been changed when the NT20 is powered,
reset the power to the NT20. The changes with the DIP switches become
effective only after the power supply is reset.
4 Operating Environment Precautions
1,2,3... 1. Do not install the PT in any of the following locations.
• Locations subject to rapid changes in temperature
• Locations subject to temperatures or humidity outside the range specified
in the specifications
• Locations subject to condensation as the result of high humidity
• Locations subject to splashing chemicals or solvents
• Locations subject to oil splashes
• Locations subject to corrosive or flammable gases
• Locations subject to strong shock or vibration
• Locations outdoors subject to direct wind and rain
• Locations subject to strong ultraviolet light
2. Take appropriate and sufficient countermeasures when installing systems
in the following locations.
• Locations subject to static electricity or other forms of noise
• Locations subject to strong electromagnetic or magnetic fields
• Locations close to power supply lines
• Locations subject to possible exposure to radioactivity
5 Application Precautions
1,2,3... 1. When unpacking the PT, check carefully for any external scratches or other
damage. Also, shake the PT gently and check for any abnormal sound.
2. Turn OFF the power supply to the PT before mounting or dismounting any
Interface Unit, such as a Memory Unit. Correctly mount the Interface Unit
according to the NT20 User's Manual.
3. Do not touch PCBs with bare hands. Discharge static electricity accumu-
lated in your body in advance.
4. The mounting panel must be between 1.6 and 4.8 mm thick. Tighten the
Mounting Brackets evenly to a torque of between 0.5 and 0.6 N·m to main-
tain water and dust resistance. Make sure the panel is not dirty or warped
and that it is strong enough to hold the PT.
5. Do not let metal particles enter the PT when preparing the panel.
6. Do not perform a dielectric voltage test on the PT.
7. Use a DC power supply that is isolated between DC output and AC input,
and has minimal fluctuation voltage.
Rated power supply voltage: 24 VDC (Allowable range: 20.4 to 27.6 VDC)
Capacity: 10 W min.
8. Use a twisted-pair cable of at least 2 mm2to connect to the power supply
terminals. Tighten the terminal screws to 0.8 N·m. Make sure the screws
are properly tightened.
9. Turn OFF the power supply to the PT before connecting or disconnecting
cables between devices.

xx
EC Directives 6
10. Always tighten the connector screws after connecting communications ca-
bles.
11. The maximum pull load for cables is 30 N. Do not apply loads greater than
this.
12. Confirm that the current capacity of the connected device is 150 mA or less
before using the 5-V power supply from pin 6 of serial port A or port B. The
5-V output of the NT20 is 150 mA maximum at 5 V ±5%.
13. Confirm the safety of the system before turning ON or OFF the power sup-
ply or pressing the reset switch.
14. The whole system may stop depending on how the power supply is turned
ON or OFF. Turn ON or OFF the power supply according to the specified
procedure.
15. Start actual system application only after sufficiently checking screen data
and the operation of the program in the PLC (host).
16. Do not press any touch switch with a force greater than 30 N.
17. Do not accidentally press touch switches when the Backlight is not lit or
when the display does not appear. Confirm the safety of the system before
pressing touch switches.
18. Signals from the touch switches may not be input if the switches are
pressed consecutively at high speed. Confirm each input before proceed-
ing to the next touch switch.
19. To ensure greater safety for numeric inputs, use the upper/lower limit set-
ting function.
20. When transferring data in screen units, also transfer any data associated
with the screen, such as memory tables or direct connection data, if any of
this data has changed.
21. To assure system safety, incorporate a program that periodically calls PT
operation bits from the host side to check that the PT is properly operating.
22. An afterimage will remain if the same patterns are displayed continuously
for extended periods of time (e.g., 24 hours). Use the screen saver or pe-
riodically change the display to prevent afterimages.
23. Do not use benzene, paint thinner, or other volatile solvents, and do not
use chemically treated cloths.
24. Do not attempt to disassemble, repair, or modify the PT in any way.
25. The backlight in the PT contains mercury. Do not dispose of the PT togeth-
er with waste to be processed at disposal plants. Dispose of the PT accord-
ing to all local laws, regulations, and ordinances as they apply.
26. Confirm the installation conditions periodically when the PT is being used
in an environment subject to oil or water.
27. Water resistance will be lost if the front sheet is not present. Confirm that
the front sheet is present before using the PT.
6 EC Directives
Conforming Directive
The NT20 PTs conform to the EMC Directive.

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EC Directives 6
EMC Directive Conformance
OMRON products are designed as electrical devices for use built into other
devices or the overall machine. As individual devices, they comply with the
related EMC standards (see note) so that they can more easily be built into
other devices or the overall machine. The actual products have been checked
for conformity to EMC standards. Whether they conform to the standards in
the system used by the customer, however, must be checked by the customer.
EMC-related performance of the OMRON devices will vary depending on the
configuration, wiring, and other conditions of the equipment or control panel
on which the OMRON devices are installed. The customer must, therefore,
perform the final check to confirm that devices and the overall machine con-
form to EMC standards.
Note Applicable EMC (Electromagnetic Compatibility) standards are as follows:
EMS (Electromagnetic Susceptibility): EN 61131-2
EMI (Electromagnetic Interference): EN 61131-2 (Radiated emission:
10-m regulations)
Complying with EC Directives
NT-series PTs comply with EC Directives. Observe the following precautions
to ensure that the customer’s device and the overall machine also comply with
EC Directives.
1,2,3... 1. The PT is designed for installation inside a control panel. The PT must be
installed within a control panel.
2. Use reinforced insulation or double insulation for the DC power supply to
the PT. Ensure that a stable power output can be provided even if a 10-ms
interruption occurs at the input.
3. The PT conforms to the EN 61131-2, but the radiated emission character-
istics (10-m regulations) may vary depending on the configuration of the
control panel used, other devices connected to the control panel, wiring,
and other conditions. You must therefore confirm that the overall machine
or equipment complies with EC Directives.