Omron SYSMAC NX series User guide

Machine Automation Controller
NX-series
Load Cell Input Unit
Startup Guide
for Weight Measurement
NX-RS□□□□
P104-E1-01

NOTE
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system,
or transmitted, in any form, or by any means, mechanical, photocopying, recording, or
otherwise, without the prior written permission of OMRON.
No patent liability is assumed with respect to the use of the information contained herein.
Moreover, because OMRON is constantly 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.

1
Introduction
The NX-series Load Cell Input Unit Startup Guide for Weight Measurement (hereinafter, may be
referred to as “this Guide”) describes the startup procedures for weight measurement in
combination with the NJ-series CPU Unit and the basic operating instructions for the Sysmac
Studio. A simple scaling system is used for the discussion. You can perform the procedures that
are presented in this Guide to quickly gain a basic understanding of how to use the Load Cell
Input Unit.
This Guide does not contain safety information and other details that are required for actual use.
Thoroughly read and understand the manuals for all of the devices that are used in this Guide to
ensure that the system is used safely. Review the entire contents of these materials, including
all safety precautions, precautions for safe use, and precautions for correct use.
Intended Audience
This Guide is intended for the following personnel.
• Personnel in charge of introducing FA systems
• Personnel in charge of designing FA systems
The personnel must also have the following knowledge.
• Knowledge of electrical systems (an electrical engineer or the equivalent)
• Knowledge of NJ-series CPU Units
• Knowledge of operation procedure of Sysmac Studio
• Knowledge of NA-series Programmable Terminal
• Knowledge of load cells
Applicable Products
This Guide covers the following products.
• Load Cell Input Units of NX-series Machine Automation Controllers
• CPU Units of NJ-series Machine Automation Controllers
• Sysmac Studio Automation Software
• NA-series Programmable Terminals
Special Information
The icons that are used in this Guide are described below.
Additional Information
Additional information to read as required.
This information is provided to increase understanding or make operation easier.
Precautions for Correct Use
Precautions on what to do and what not to do to ensure proper operation and
performance.

2
Terms and Conditions Agreement
Warranties
(a) Exclusive Warranty. Omron’s exclusive warranty is that the Products will be free from defects in
materials and workmanship for a period of twelve months from the date of sale by Omron (or such
other period expressed in writing by Omron). Omron disclaims all other warranties, express or
implied.
(b) Limitations. OMRON MAKES NO WARRANTY OR REPRESENTATION, EXPRESS OR IMPLIED,
ABOUT NON-INFRINGEMENT, MERCHANTABILITY OR FITNESS FORA PARTICULAR
PURPOSE OF THE PRODUCTS. BUYER ACKNOWLEDGES THAT ITALONE HAS DETERMINED
THAT THE
PRODUCTS WILL SUITABLY MEET THE REQUIREMENTS OF THEIR INTENDED USE.
Omron further disclaims all warranties and responsibility of any type for claims or expenses based on
infringement by the Products or otherwise of any intellectual property right. (c) Buyer Remedy.
Omron’s sole obligation hereunder shall be, at Omron’s election, to (i) replace (in the form originally
shipped with Buyer responsible for labor charges for removal or replacement thereof) the
non-complying Product, (ii) repair the non-complying Product, or (iii) repay or credit Buyer an amount
equal to the purchase price of the non-complying Product; provided that in no event shall Omron be
responsible for warranty, repair, indemnity or any other claims or expenses 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. Return of
any Products by Buyer must be approved in writing by Omron before shipment. Omron Companies
shall not be liable for the suitability or unsuitability or the results from the use of Products in
combination with any electrical or electronic components, circuits, system assemblies or any other
materials or substances or environments.Any advice, recommendations or information given orally or
in writing, are not to be construed as an amendment or addition to the above warranty.
See http://www.omron.com/global/ or contact your Omron representative for published information.
Limitation on Liability; Etc
OMRON COMPANIES SHALL NOT BE LIABLE FOR SPECIAL, INDIRECT, INCIDENTAL, OR
CONSEQUENTIAL DAMAGES, LOSS OF PROFITS OR PRODUCTION OR COMMERCIAL LOSS
INANY WAY CONNECTED WITH THE PRODUCTS, WHETHER SUCH CLAIM IS BASED IN
CONTRACT, WARRANTY, NEGLIGENCE OR STRICT LIABILITY.
Further, in no event shall liability of Omron Companies exceed the individual price of the Product on
which liability is asserted.
Suitability of Use
Omron Companies shall not be responsible for conformity with any standards, codes or regulations
which apply to the combination of the Product in the Buyer’s application or use of the Product.At
Buyer’s request, Omron will provide applicable third party certification documents identifying ratings
and limitations of use which apply to the Product. This information by itself is not sufficient for a
complete determination of the suitability of the Product in combination with the end product, machine,

3
system, or other application or use. Buyer shall be solely responsible for determining appropriateness
of the particular Product with respect to Buyer’s application, product or system. Buyer shall take
application responsibility in all cases.
NEVER USE THE PRODUCT FOR AN APPLICATION INVOLVING SERIOUS RISK TO LIFE OR
PROPERTY WITHOUT ENSURING THAT THE SYSTEM AS AWHOLE HAS BEEN DESIGNED TO
ADDRESS THE RISKS, AND THAT THE OMRON PRODUCT(S) IS PROPERLY RATEDAND
INSTALLED FOR THE INTENDED USE WITHIN THE OVERALL EQUIPMENT OR SYSTEM.
Programmable Products
Omron Companies shall not be responsible for the user’s programming of a programmable Product,
or any consequence thereof.
Performance Data
Data presented in Omron Company websites, catalogs and other materials 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 user must correlate it to actual application requirements.Actual
performance is subject to the Omron’s Warranty and Limitations of Liability.
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 part numbers when published ratings or features are
changed, or when significant construction changes are made. However, some specifications of the
Product may be changed without any notice. When in doubt, special part numbers may be assigned
to fix or establish key specifications for your application. Please consult with your Omron’s
representative at any time to confirm actual specifications of purchased Product.
Errors and Omissions
Information presented by Omron Companies has been checked and is believed to be accurate;
however, no responsibility is assumed for clerical, typographical or proofreading errors or omissions.

4
Sysmac Studio Automation Software
1. WARRANTY
(1) The warranty period for the Software is one year from the date of purchase, unless otherwise
specifically agreed.
(2) If the User discovers defect of the Software (substantial non-conformity with the manual), and
return it to OMRON within the above warranty period, OMRON will replace the Software without
charge by offering media or download from OMRON’s website.And if the User discovers defect of
media which is attributable to OMRON and return it to OMRON within the above warranty period,
OMRON will replace defective media without charge. If OMRON is unable to replace defective media
or correct the Software, the liability of OMRON and the User’s remedy shall be limited to the refund of
the license fee paid to OMRON for the Software.
2. LIMITATION OF LIABILITY
(1) THE ABOVE WARRANTY SHALL CONSTITUTE THE USER’S SOLEAND EXCLUSIVE
REMEDIES AGAINST OMRON AND THERE ARE NO OTHER WARRANTIES, EXPRESSED OR
IMPLIED, INCLUDING BUT NOT LIMITED TO, WARRANTY OF MERCHANTABILITY OR FITNESS
FOR PARTICULAR PURPOSE. IN NO EVENT, OMRON WILLBE LIABLE FORANY LOST
PROFITS OR OTHER INDIRECT, INCIDENTAL, SPECIAL OR CONSEQUENTIAL DAMAGES
ARISING OUT OF USE OF THE SOFTWARE.
(2)OMRON SHALL HAVE NO LIABILITY FOR DEFECT OF THE SOFTWARE BASED ON
MODIFICATION OR ALTERNATION TO THE SOFTWARE BY THE USER OR ANY THIRD PARTY.
(3)OMRON SHALL HAVE NO LIABILITY FOR SOFTWARE DEVELOPED BY THE USER OR ANY
THIRD PARTY BASED ON THE SOFTWARE ORANY CONSEQUENCE THEREOF.
3. APPLICABLE CONDITIONS
USER SHALLNOT USE THE SOFTWARE FOR THE PURPOSE THAT IS NOT PROVIDED IN THE
ATTACHED USER MANUAL.
4. CHANGE IN SPECIFICATION
The software specifications and accessories may be changed at any time based on improvements
and other reasons.
5. EXTENT OF SERVICE
The license fee of the Software does not include service costs, such as dispatching technical staff.
6. 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.

5
Precautions
• When building a system, check the specifications for all devices and equipment that will make
up the system and make sure that the OMRON products are used well within their rated
specifications and performances. Safety measures, such as safety circuits, must be
implemented in order to minimize the risks in the event of a malfunction.
• Thoroughly read and understand the manuals for all devices and equipment that will make up
the system to ensure that the system is used safely. Review the entire contents of these
manuals, including all safety precautions, precautions for safe use, and precautions for
correct use.
• Confirm all regulations, standards, and restrictions that the system must adhere to.
Trademarks
• Sysmac and SYSMAC are trademarks or registered trademarks of OMRON Corporation in
Japan and other countries for OMRON factory automation products.
• EtherCAT® is registered trademark and patented technology, licensed by Beckhoff
Automation GmbH, Germany.
• Microsoft product screen shot(s) reprinted with permission from Microsoft Corporation.
Other company names and product names in this Guide are the trademarks or registered
trademarks of their respective companies.
Software Licenses and Copyrights
The NJ-series CPU Units and Sysmac Studio incorporate certain third party software. The
license and copyright information associated with this software is available at
http://www.fa.omron.co.jp/nj_info_e/.

6
Related Manuals
The following manuals are related to this Guide. Use these manuals for reference.
Manual name
Cat. No.
Model numbers
Application
Description
NX-series Load Cell Input
Unit Startup Guide for
Weight Measurement
(this guide)
P104 NX-RS1201 Learning the startup
procedures for a weight
measuring system using the
NX-series Load Cell Input
Unit
The startup procedures for a weight
measuring system using the
NX-series Load Cell Input Unit are
described.
NX-series Load Cell Input
Unit User’s Manual W565 NX-RS□□□□ Learning how to use an NX-series
Load Cell Input Unit
The hardware, setup methods, and
functions of the NX-series Load Cell
Input Unit are described.
NJ/NX-series Sysmac
Library User’s Manual for
Weighing Control Library
W569 SYSMAC-XR010 Learning the function block
specifications in the
Weighing Control Library
Information required to use the
Weighing Control Library is
described.
Sysmac Studio Version 1
Operation Manual W504 SYSMAC-SE2□□□ Learning about the operating procedures and
functions of the Sysmac
Studio.
The operating procedures of the
Sysmac Studio are described.
NJ-series CPU Unit
Hardware User’s Manual W500 NJ501-□□□□ NJ301-□□□□ Learning the basic specifications of the
NJ-series CPU Units,
including introductory
information, designing,
installation, and
maintenance.
Mainly hardware
information is provided.
An introduction to the entire
NJ-series system is provided along
with the following information on a
Controller built with an NJ501 CPU
Unit.
・Features and system configuration
・Introduction
・Part names and functions
・General specifications
・Installation and wiring
・Maintenance and inspection
Use this manual together with the
NJ-series CPU Unit Software User’s
Manual (Cat. No. W501).
NJ-series CPU Unit
Software User’s Manual W501 NJ501-□□□□ NJ301-□□□□ Learning how to program and set up an NJ-series
CPU Unit.
Mainly software information
is provided.
The following information is provided
on a Controller built with an NJ-series
CPU Unit.
・CPU Unit operation
・CPU Unit features
・Initial settings
・Programming based on IEC
61131-3 language specifications
Use this manual together with the
NJ-series CPU Unit Hardware User’s
Manual (Cat. No.W500).

7
Manual name
Cat. No.
Model numbers
Application
Description
NJ-series
Troubleshooting Manual W503 NJ501-□□□□ NJ301-□□□□ Learning about the errors that may be detected in an
NJ-series Controller.
Concepts on managing errors that
may be detected in an NJ-series
Controller and information on
individual errors are described.
Use this manual together with the
NJ-series CPU Unit Hardware User’s
Manual (Cat. No.W500) and
NJ-series CPU Unit Software User’s
Manual (Cat. No. W501).
NX-series Data
Reference Manual W525 NX-□□□□□□ Referencing lists of the data that is required to configure
systems with NX-series
Units
Lists of the power consumptions,
weights, and other NX Unit data that
is required to configure systems with
NX-series Units are provided.
NX-series EtherCAT
Coupler Unit User’s
Manual
W519 NX-ECC201
NX-ECC202
NX-ECC203
Leaning how to use an
NX-series EtherCAT
Coupler Unit and EtherCAT
Slave Terminals
The following items are described:
the overall system and configuration
methods of an EtherCAT Slave
Terminal (which consists of an
NX-series EtherCAT Coupler Unit
and NX Units), and information on
hardware, setup, and functions to set
up, control, and monitor NX Units
through EtherCAT.
NA-series Programmable
Terminal Hardware
User’s Manual
V117 NA5-□W□□□□
NA5-□□W□□□□ Learning the specifications and settings required to
install an NA-series PT and
connect peripheral devices.
Information is provided on NA-series
PT specifications, part names,
installation procedures, and
procedures to connect an NA Unit to
peripheral devices.
Information is also provided on
maintenance after operation and
troubleshooting.
NA-series Programmable
Terminal Software User’s
Manual
V118 NA5-□W□□□□
NA5-□□W□□□□ Learning about NA-series PT pages and object
functions.
NA-series PT pages and object
functions are described.
NA-series Programmable
Terminal Device
Connection User’s
Manual
V119 NA5-□W□□□□
NA5-□□W□□□□ Learning the specifications required to connect devices
to an NA-series PT.
Information is provided on connection
procedures and setting procedures to
connect an NA-series PT to a
Controller or other device.
NA-series Programmable
Terminal
Startup Guide
V120 NA5-□W□□□□
NA5-□□W□□□□ Learning in concrete terms information required to
install and start the
operation of an NA-series
PT.
The part names and installation
procedures are described followed by
page creation and transfer
procedures with the Sysmac Studio.
Also operation, maintenance, and
inspection procedures after the
project is transferred are described.
Sample screen captures are provided
as examples.

8
Revision History
A manual revision code appears as a suffix to the catalog number on the front and back covers
of the manual.
Revision code
Date
Revised content
01 April 2016 Original production
Cat. No.
P104-E1-01
Revision

9
CONTENTS
Introduction..................................................................................1
Intended Audience.....................................................................................................1
Applicable Products...................................................................................................1
Special Information....................................................................................................1
Terms and Conditions Agreement.............................................2
Sysmac Studio Automation Software....................................................................4
Precautions..................................................................................5
Trademarks...............................................................................................................5
Software Licenses and Copyrights........................................................................5
Related Manuals..........................................................................6
Revision History..........................................................................8
1. System to Construct and Configuration Devices...........10
1.1. System Configuration and Configuration Devices..........................................10
1.2. Applicable Load Cells......................................................................................13
2. Before You Begin ...............................................................14
2.1. Wiring the Devices and Installing the Software..............................................14
3. Starting Up the Weight Measuring System .....................15
3.1. Steps to Start Up the Weight Measuring System............................................15
3.2. Installing Wiring for the Load Cell Input Unit...................................................16
3.2.1. Wiring Example with 6-wire Connection................................................17
3.2.2. Wiring Example with 4-wire Connection................................................17
3.2.3. Wiring Example of Parallel Connection.................................................18
3.3. Performing a Calibration.................................................................................19
3.3.1. Overview of Calibration.........................................................................19
3.3.2. Performing anActual Load Calibration..................................................20
3.3.3. Performing Equivalent Input Calibration................................................26
3.4. Checking Measurement Values......................................................................29
3.4.1. I/O Data Allocation.................................................................................29
3.4.2. Checking Measurement Values.............................................................32
4. Appendices.........................................................................37
4.1. Features for Stable Measurement...................................................................37
4.2. Data Backup When Replacing the Load Cell Input Unit.................................37
4.3. Weighing Control Library of Sysmac Library ..................................................37

10
1. System to Construct and Configuration Devices
1.1. System Configuration and Configuration Devices
This section describes the system configuration and configuration devices used in this Guide.
The system configuration is shown below. This system is a scaling system where a measured
material is placed onto the scale to measure its weight.
The load cell output, which is obtained from the data inputted to the Load Cell Input Unit, is
converted into the weight value to measure the weight of the measured material. The weight
value converted by the Load Cell Input Unit is sent to a CPU Unit and displayed on the
Programmable Terminal.
NX-series Load Cell Input
Unit (NX-RS1201)
NJ-series CPU Unit
(NJ501-1300)
Scale
Load cell
Measured material
NX-series EtherCAT
Coupler Unit (NX-ECC203)
Shielded cable
Programmable Terminal
(NA5-12W101S)
Unit power supply
EtherCAT
communications
cable
Personal computer
(Sysmac Studio
already installed）
USB cable
NJ-series Power Supply
Unit (NJ-PA3001)
24 VDC power supply
(S8JX-N01524CD)
EtherNet/IP
communications cable
USB cable
Additional Information
Refer to the NJ/NX-series Sysmac Library User’s Manual for Weighing Control Library
(Cat. No. W569) for examples of use in other weighing systems.
This Guide’s examples assume the specifications of the used load cell as follows.
Connection line
Rated capacity
Rated output
Zero balance
6-wire type or 4-wire type
20 kg
2 mV/V
1 μV/V
This Guide’s examples assume the weights of the scale and the measured material as
follows.
Item
Weight
Scale
5 kg
Measured material
10 kg

11
Additional Information
Select the load cell’s rated capacity, scale, and measured material so as to satisfy the
following relationship:
Rated capacity of the load cell ≥Weight of the scale + Maximum weight of the measured
material
The table below shows the models of the devices used for explanation in this Guide. When
selecting devices for actual use, refer to their respective manuals.
Device name
Model
Manual name
NX-series Load Cell Input
Unit NX-RS1201 (version 1.0) NX-series Load Cell Input Unit User’s Manual (Cat.
No. W565)
NJ-series CPU Unit NJ501-1300 (version 1.05 or
later) NJ-series CPU Unit Hardware User’s Manual
(Cat. No. W500).
NJ-series Power Supply
Unit NJ-PA3001
EtherCAT communications
cables
EtherNet/IP
communications cables
XS5W-T421-CMD-K
NX-series EtherCAT
Coupler Unit NX-ECC203 (version 1.0 or later) NX-series EtherCAT Coupler Unit User’s
Manual (Cat. No. W519)
Ferrule H0.25/12 (used for other than
ground terminals)
AI2,5-10 (used for ground
terminals)
Programmable Terminal NA5-12W101S (Ver.1.01) NA-series Programmable
Terminal Hardware User’s
Manual (Cat. No. V117)
Switching power supply (24
VDC power supply) S8JX-N01524CD [Instruction Manual] S8JX Switching Power Supply
(1141546-0)
Load cell Commercially available load
cell*1
－
USB cable Commercially available USB
cable*2
－
Shielded cable Commercially available shielded
cable*3
－
Scale －－
Standard weight －－
*1. For the load cells that can be connected to the NX-RS1201 Load Cell Input Unit, refer to
1.2 Applicable Load Cells.
*2. Use a USB2.0 (or 1.1) cable (A to B connector) with a maximum length of 5.0 meters.

12
*3. For use of a 4-wire load cell, use a 4-conductor type; for use of a 6-wire load cell, use a
6-conductor type. In addition, the wire resistance should be less than 5 Ω.
The table below shows the software, used for explanation in this Guide, to install on the
personal computer (OS: Windows 7 64-bit edition).
Manufacturer
Name
Version
OMRON
Corporation Sysmac Studio Version 1.16 or later

13
1.2. Applicable Load Cells
The table below shows the specifications of the NX-RS1201 Load Cell Input Unit used for
explanation in this Guide. Select the applicable load cell within the range of specifications as
shown in the table.
Load cell excitation
voltage
Input range
Connection to load
cell
Number of load cell
input
5 VDC ±10%
Output current: 60mA
or less
-5.0 to +5.0 mV/V 6-wire type or 4-wire
type 1
For use of a load cell for which a load cell excitation voltage of more than 5 VDC is
recommended, ask the load cell’s manufacturer if the use of 5 VDC is acceptable.*1 You cannot
use a load cell whose load cell excitation voltage is less than 5 VDC in its specifications.
For use of multiple load cells in parallel connection, the total current supplied to the load cell
should be 60 mA or less.
*1. For example, if the load cell excitation voltage is specified as 5 to 10 VDC in the
specifications, its use is possible. If specified as 10 VDC, ask the load cell’s manufacturer if
the use of 5 VDC is acceptable.

14
2. Before You Begin
2.1. Wiring the Devices and Installing the Software
Wire the devices and install the Sysmac Studio to the personal computer as described in 1.1.
System Configuration and Configuration Devices.
Additional Information
Refer to 3.2 Installing Wiring for the Load Cell Input Unit for how to wire Load Cell
Input Unit and a load cell.
For wiring and usage of the NJ-series CPU Unit, NX-series EtherCAT Coupler Unit,
and Programmable Terminal, refer to their respective manuals. For manual
information, see Related Manuals.
Refer to the Sysmac Studio Version 1 Operation Manual (Cat. No. W504) for how to
install the Sysmac Studio.
NX-series
Load Cell Input Unit
(NX-RS1201)
NJ-series CPU Unit
(NJ501-1300)
Scale
Load cell
Measured material
NX-series
EtherCAT Coupler Unit
(NX-ECC203)
Shielded cable
Programmable Terminal
(NA5-12W101S)
Unit power supply
EtherCAT
communications
cable
Personal computer
(Sysmac Studio
already installed)
USB cable
NJ-series Power Supply Unit
(NJ-PA3001)
24 VDC power supply
(S8JX-N01524CD)
EtherNet/IP
communications cable
USB cable

15
3. Starting Up the Weight Measuring System
3.1. Steps to Start Up the Weight Measuring System
The steps to start up the weight measuring system using a scale are as follows:
3.2
Installing Wiring for the Load Cell
Input Unit Install wiring between the Load Cell Input
Unit and a load cell.
The wiring configuration is different between
a 4-wire load cell and a 6-wire load cell.
▼
3.3 Performing a Calibration Be sure to perform calibration before
measurement in order to measure the weight
and force using the Load Cell Input Unit.
There are two calibration methods for the
Load Cell Input Unit:
・Actual load calibration
・Equivalent input calibration
▼
3.4 Checking Measurement Values Place a measured material onto the scale of
the scale weighing system and check its
measurement value (weight value).
This Guide covers the Load Cell Input Unit’s startup procedures only. For wiring and usage of the
NJ-series CPU Unit, NX-series EtherCAT Coupler Unit, and Programmable Terminal, refer to
their respective manuals. For manual information, see Related Manuals.

16
3.2. Installing Wiring for the Load Cell Input Unit
This section shows the examples of wiring to a load cell.
You can connect the Load Cell Input Unit to a load cell with a 6-wire or 4-wire connection. We
recommend that you use a 6-wire connection for connecting the load cell with the Load Cell
Input Unit to achieve high-precision measurements.
Additional Information
The Load Cell Input Unit uses screwless clamping terminal blocks. The use of
ferrules makes wiring an easy matter of inserting them. The screwless design greatly
reduces wiring work.
The sensor disconnection test is available for the Load Cell Input Unit. Using the
sensor disconnection test after the completion of wiring allows you to check whether
there is a cable disconnection and a non-connected wiring. Refer to the NX-series
Load Cell Input User’s Manual (Cat. No. W565) for details on the sensor
disconnection test.
Precautions for Correct Use
Use a shielded cable to connect to the load cell. Connect the shield wire to the SHLD
terminal on the Load Cell Input Unit.
Ground the functional ground terminal on the Load Cell Input Unit to 100 Ω or less.
We recommend that you use a 6-
wire connection for connecting the load cell with the
Load Cell Input Unit to achieve high-precision measurements. When you use a 4-
wire
connection, the measurement resolution of wiring resistance decreases due to
temperature changes.

Keep the wiring resistance from the load cell to the Load Cell Input Unit to 5 Ω or less
while in use.

Wire the cable that connects the load cell and the Load Cell Input Unit separately from
AC power supply lines or power lines in
order to avoid the effects of the noise. Do not
place such lines in the same duct.
Insert a noise filter into the power supply input section if noise may overlap from
power supply lines when using the same power supply to power an electrical welder
or an electric discharge machine, or there is a high-frequency source nearby.

17
3.2.1. Wiring Example with 6-wire Connection
For the connection between a 6-wire load cell and the Load Cell Input Unit, lay the wiring as
in the figure below.
Load cell
＋IN
－IN
－OUT
＋OUT
Shielded cable
SIG+
SIG-
EXC+
EXC-
S+
S-
EXC+
EXC-
NC
NC
NC
NC
SHLD
SHLD
Ground of 100 Ωor less
Load Cell Input Unit
A1
A8
B1
B8
3.2.2. Wiring Example with 4-wire Connection
For the connection between a 4-wire load cell and the Load Cell Input Unit, lay the wiring as in
the figure below.
The application of 4-wire connection leads to a decrease in measurement precision due to
temperature variations of the wiring resistance compared to the 6-wire connection.
Load cell
＋IN
－IN
－OUT
＋OUT
Shielded cable
SIG+
SIG-
EXC+
EXC-
S+
S-
EXC+
EXC-
NC
NC
NC
NC
SHLD
SHLD
Load Cell Input Unit
Ground of 100 Ωor less
A1
A8
B1
B8
Terminal block
Terminal block

18
3.2.3. Wiring Example of Parallel Connection
The system configuration example in this Guide is based on the assumption that one load cell is in
use, but multiple load cells can be connected in parallel by using a summing box as in the diagram
below. Refer to 4-4 Wiring the Connected External Devices described in the NX-series Load Cell
Input Unit User’s Manual (Cat. No. W565).
Load Cell
Input Unit
Summing box
Shielded cable
6-wire connection
Load cell
Load cell
Load cell
Load cell
Precautions for Correct Use
When you use the Load Cell Input Unit with a 4-wire connection, always connect S+
terminal with EXC+ terminal, and S- terminal with EXC- terminal on the terminal block. If
they are not connected, the Load Cell Input Unit does not operate normally.