Mitsubishi Electric MELSEC iQ-R RJ71LP21-25 User manual

MELSEC iQ-R MELSECNET/H Network Module
User's Manual (Startup)
-RJ71LP21-25

1
SAFETY PRECAUTIONS
(Read these precautions before using this product.)
Before using this product, please read this manual and the relevant manuals carefully and pay full attention to safety to handle
the product correctly.
The precautions given in this manual are concerned with this product only. For the safety precautions of the programmable
controller system, refer to the MELSEC iQ-R Module Configuration Manual.
In this manual, the safety precautions are classified into two levels: " WARNING" and " CAUTION".
Under some circumstances, failure to observe the precautions given under " CAUTION" may lead to serious
consequences.
Observe the precautions of both levels because they are important for personal and system safety.
Make sure that the end users read this manual and then keep the manual in a safe place for future reference.
WARNING Indicates that incorrect handling may cause hazardous conditions, resulting in
death or severe injury.
CAUTION Indicates that incorrect handling may cause hazardous conditions, resulting in
minor or moderate injury or property damage.

2
[Design Precautions]
WARNING
●Configure safety circuits external to the programmable controller to ensure that the entire system
operates safely even when a fault occurs in the external power supply or the programmable controller.
Failure to do so may result in an accident due to an incorrect output or malfunction.
(1) Emergency stop circuits, protection circuits, and protective interlock circuits for conflicting
operations (such as forward/reverse rotations or upper/lower limit positioning) must be configured
external to the programmable controller.
(2) When the programmable controller detects an abnormal condition, it stops the operation and all
outputs are:
• Turned off if the overcurrent or overvoltage protection of the power supply module is activated.
• Held or turned off according to the parameter setting if the self-diagnostic function of the CPU
module detects an error such as a watchdog timer error.
(3) All outputs may be turned on if an error occurs in a part, such as an I/O control part, where the
CPU module cannot detect any error. To ensure safety operation in such a case, provide a safety
mechanism or a fail-safe circuit external to the programmable controller. For a fail-safe circuit
example, refer to "General Safety Requirements" in the MELSEC iQ-R Module Configuration
Manual.
(4) Outputs may remain on or off due to a failure of a component such as a relay and transistor in an
output circuit. Configure an external circuit for monitoring output signals that could cause a
serious accident.
●In an output circuit, when a load current exceeding the rated current or an overcurrent caused by a
load short-circuit flows for a long time, it may cause smoke and fire. To prevent this, configure an
external safety circuit, such as a fuse.
●Configure a circuit so that the programmable controller is turned on first and then the external power
supply. If the external power supply is turned on first, an accident may occur due to an incorrect output
or malfunction.
●For the operating status of each station after a communication failure, refer to the troubleshooting in
the MELSEC iQ-R MELSECNET/H Network Module User's Manual (Application). Incorrect output or
malfunction due to a communication failure may result in an accident.
●When connecting an external device with a CPU module or intelligent function module to modify data
of a running programmable controller, configure an interlock circuit in the program to ensure that the
entire system will always operate safely. For other forms of control (such as program modification,
parameter change, forced output, or operating status change) of a running programmable controller,
read the relevant manuals carefully and ensure that the operation is safe before proceeding. Improper
operation may damage machines or cause accidents.
●Especially, when a remote programmable controller is controlled by an external device, immediate
action cannot be taken if a problem occurs in the programmable controller due to a communication
failure. To prevent this, configure an interlock circuit in the program, and determine corrective actions
to be taken between the external device and CPU module in case of a communication failure.

3
[Design Precautions]
[Design Precautions]
WARNING
●Do not write any data to the "system area" and "write-protect area" of the buffer memory in the
module. Also, do not use any "use prohibited" signals as an output signal from the CPU module to
each module. Doing so may cause malfunction of the programmable controller system. For the
"system area", "write-protect area", and the "use prohibited" signals, refer to the user's manual for the
module used.
●If a communication cable is disconnected, the network may be unstable, resulting in a communication
failure of multiple stations. Configure an interlock circuit in the program to ensure that the entire
system will always operate safely even if communications fail. Incorrect output or malfunction due to a
communication failure may result in an accident.
●To maintain the safety of the programmable controller system against unauthorized access from
external devices via the network, take appropriate measures. To maintain the safety against
unauthorized access via the Internet, take measures such as installing a firewall.
CAUTION
●Do not install the control lines or communication cables together with the main circuit lines or power
cables. Keep a distance of 100mm or more between them. Failure to do so may result in malfunction
due to noise.
●During control of an inductive load such as a lamp, heater, or solenoid valve, a large current
(approximately ten times greater than normal) may flow when the output is turned from off to on.
Therefore, use a module that has a sufficient current rating.
●After the CPU module is powered on or is reset, the time taken to enter the RUN status varies
depending on the system configuration, parameter settings, and/or program size. Design circuits so
that the entire system will always operate safely, regardless of the time.
●Do not power off the programmable controller or reset the CPU module while the settings are being
written. Doing so will make the data in the flash ROM and SD memory card undefined. The values
need to be set in the buffer memory and written to the flash ROM and SD memory card again. Doing
so also may cause malfunction or failure of the module.

4
[Installation Precautions]
[Installation Precautions]
[Wiring Precautions]
WARNING
●Shut off the external power supply (all phases) used in the system before mounting or removing the
module. Failure to do so may result in electric shock or cause the module to fail or malfunction.
CAUTION
●Use the programmable controller in an environment that meets the general specifications in the Safety
Guidelines included with the base unit. Failure to do so may result in electric shock, fire, malfunction,
or damage to or deterioration of the product.
●To mount a module, place the concave part(s) located at the bottom onto the guide(s) of the base unit,
and push in the module until the hook(s) located at the top snaps into place. Incorrect interconnection
may cause malfunction, failure, or drop of the module.
●To mount a module with no module fixing hook, place the concave part(s) located at the bottom onto
the guide(s) of the base unit, push in the module, and fix it with screw(s). Incorrect interconnection
may cause malfunction, failure, or drop of the module.
●When using the programmable controller in an environment of frequent vibrations, fix the module with
a screw.
●Tighten the screws within the specified torque range. Undertightening can cause drop of the screw,
short circuit, or malfunction. Overtightening can damage the screw and/or module, resulting in drop,
short circuit, or malfunction.
●When using an extension cable, connect it to the extension cable connector of the base unit securely.
Check the connection for looseness. Poor contact may cause malfunction.
●When using an SD memory card, fully insert it into the SD memory card slot. Check that it is inserted
completely. Poor contact may cause malfunction.
●Securely insert an extended SRAM cassette or a battery-less option cassette into the cassette
connector of the CPU module. After insertion, close the cassette cover and check that the cassette is
inserted completely. Poor contact may cause malfunction.
●Do not directly touch any conductive parts and electronic components of the module, SD memory
card, extended SRAM cassette, battery-less option cassette, or connector. Doing so can cause
malfunction or failure of the module.
WARNING
●Shut off the external power supply (all phases) used in the system before installation and wiring.
Failure to do so may result in electric shock or cause the module to fail or malfunction.
●After installation and wiring, attach a blank cover module (RG60) to each empty slot and an included
extension connector protective cover to the unused extension cable connector before powering on the
system for operation. Failure to do so may result in electric shock.

5
[Wiring Precautions]
CAUTION
●Individually ground the FG and LG terminals of the programmable controller with a ground resistance
of 100 ohms or less. Failure to do so may result in electric shock or malfunction.
●Use applicable solderless terminals and tighten them within the specified torque range. If any spade
solderless terminal is used, it may be disconnected when the terminal screw comes loose, resulting in
failure.
●Check the rated voltage and signal layout before wiring to the module, and connect the cables
correctly. Connecting a power supply with a different voltage rating or incorrect wiring may cause fire
or failure.
●Connectors for external devices must be crimped or pressed with the tool specified by the
manufacturer, or must be correctly soldered. Incomplete connections may cause short circuit, fire, or
malfunction.
●Securely connect the connector to the module. Poor contact may cause malfunction.
●Do not install the control lines or communication cables together with the main circuit lines or power
cables. Keep a distance of 100mm or more between them. Failure to do so may result in malfunction
due to noise.
●Place the cables in a duct or clamp them. If not, dangling cables may swing or inadvertently be pulled,
resulting in malfunction or damage to modules or cables.
In addition, the weight of the cables may put stress on modules in an environment of strong vibrations
and shocks.
Do not clamp the extension cables with the jacket stripped. Doing so may change the characteristics
of the cables, resulting in malfunction.
●Check the interface type and correctly connect the cable. Incorrect wiring (connecting the cable to an
incorrect interface) may cause failure of the module and external device.
●Tighten the terminal screws or connector screws within the specified torque range. Undertightening
can cause drop of the screw, short circuit, fire, or malfunction. Overtightening can damage the screw
and/or module, resulting in drop, short circuit, fire, or malfunction.
●When disconnecting the cable from the module, do not pull the cable by the cable part. For the cable
with connector, hold the connector part of the cable. For the cable connected to the terminal block,
loosen the terminal screw. Pulling the cable connected to the module may result in malfunction or
damage to the module or cable.
●Prevent foreign matter such as dust or wire chips from entering the module. Such foreign matter can
cause a fire, failure, or malfunction.
●A protective film is attached to the top of the module to prevent foreign matter, such as wire chips,
from entering the module during wiring. Do not remove the film during wiring. Remove it for heat
dissipation before system operation.

6
[Wiring Precautions]
[Startup and Maintenance Precautions]
[Startup and Maintenance Precautions]
CAUTION
●Programmable controllers must be installed in control panels. Connect the main power supply to the
power supply module in the control panel through a relay terminal block. Wiring and replacement of a
power supply module must be performed by qualified maintenance personnel with knowledge of
protection against electric shock. For wiring, refer to the MELSEC iQ-R Module Configuration Manual.
●For Ethernet cables to be used in the system, select the ones that meet the specifications in the user's
manual for the module used. If not, normal data transmission is not guaranteed.
●For optical fiber cables to be used in the system, select the ones that meet the specifications in this
manual. If not, normal data transmission is not guaranteed.
WARNING
●Do not touch any terminal while power is on. Doing so will cause electric shock or malfunction.
●Shut off the external power supply (all phases) used in the system before cleaning the module or
retightening the terminal screws, connector screws, or module fixing screws. Failure to do so may
result in electric shock.
CAUTION
●When connecting an external device with a CPU module or intelligent function module to modify data
of a running programmable controller, configure an interlock circuit in the program to ensure that the
entire system will always operate safely. For other forms of control (such as program modification,
parameter change, forced output, or operating status change) of a running programmable controller,
read the relevant manuals carefully and ensure that the operation is safe before proceeding. Improper
operation may damage machines or cause accidents.
●Especially, when a remote programmable controller is controlled by an external device, immediate
action cannot be taken if a problem occurs in the programmable controller due to a communication
failure. To prevent this, configure an interlock circuit in the program, and determine corrective actions
to be taken between the external device and CPU module in case of a communication failure.
●Do not disassemble or modify the modules. Doing so may cause failure, malfunction, injury, or a fire.
●Use any radio communication device such as a cellular phone or PHS (Personal Handy-phone
System) more than 25cm away in all directions from the programmable controller. Failure to do so
may cause malfunction.

7
[Startup and Maintenance Precautions]
[Operating Precautions]
CAUTION
●Shut off the external power supply (all phases) used in the system before mounting or removing the
module. Failure to do so may cause the module to fail or malfunction.
●Tighten the screws within the specified torque range. Undertightening can cause drop of the
component or wire, short circuit, or malfunction. Overtightening can damage the screw and/or module,
resulting in drop, short circuit, or malfunction.
●After the first use of the product, do not perform each of the following operations more than 50 times
(IEC 61131-2/JIS B 3502 compliant).
Exceeding the limit may cause malfunction.
• Mounting/removing the module to/from the base unit
• Inserting/removing the extended SRAM cassette or battery-less option cassette to/from the
CPU module
• Mounting/removing the terminal block to/from the module
●After the first use of the product, do not insert/remove the SD memory card to/from the CPU module
more than 500 times. Exceeding the limit may cause malfunction.
●Do not touch the metal terminals on the back side of the SD memory card. Doing so may cause
malfunction or failure of the module.
●Do not touch the integrated circuits on the circuit board of an extended SRAM cassette or a battery-
less option cassette. Doing so may cause malfunction or failure of the module.
●Startup and maintenance of a control panel must be performed by qualified maintenance personnel
with knowledge of protection against electric shock. Lock the control panel so that only qualified
maintenance personnel can operate it.
●Before handling the module, touch a conducting object such as a grounded metal to discharge the
static electricity from the human body. Failure to do so may cause the module to fail or malfunction.
CAUTION
●When changing data and operating status, and modifying program of the running programmable
controller from an external device such as a personal computer connected to an intelligent function
module, read relevant manuals carefully and ensure the safety before operation. Incorrect change or
modification may cause system malfunction, damage to the machines, or accidents.

8
[Disposal Precautions]
[Transportation Precautions]
CAUTION
●When disposing of this product, treat it as industrial waste.
CAUTION
●The halogens (such as fluorine, chlorine, bromine, and iodine), which are contained in a fumigant
used for disinfection and pest control of wood packaging materials, may cause failure of the product.
Prevent the entry of fumigant residues into the product or consider other methods (such as heat
treatment) instead of fumigation. The disinfection and pest control measures must be applied to
unprocessed raw wood.

9
CONDITIONS OF USE FOR THE PRODUCT
INTRODUCTION
Thank you for purchasing the Mitsubishi Electric MELSEC iQ-R series programmable controllers.
This manual describes the procedures, system configuration, and wiring of the relevant products listed below.
Before using this product, please read this manual and the relevant manuals carefully and develop familiarity with the
functions and performance of the MELSEC iQ-R series programmable controller to handle the product correctly.
When applying the program examples provided in this manual to an actual system, ensure the applicability and confirm that it
will not cause system control problems.
Please make sure that the end users read this manual.
Relevant product
RJ71LP21-25
(1) Mitsubishi programmable controller ("the PRODUCT") shall be used in conditions;
i) where any problem, fault or failure occurring in the PRODUCT, if any, shall not lead to any major or serious accident;
and
ii) where the backup and fail-safe function are systematically or automatically provided outside of the PRODUCT for the
case of any problem, fault or failure occurring in the PRODUCT.
(2) The PRODUCT has been designed and manufactured for the purpose of being used in general industries.
MITSUBISHI SHALL HAVE NO RESPONSIBILITY OR LIABILITY (INCLUDING, BUT NOT LIMITED TO ANY AND ALL
RESPONSIBILITY OR LIABILITY BASED ON CONTRACT, WARRANTY, TORT, PRODUCT LIABILITY) FOR ANY
INJURY OR DEATH TO PERSONS OR LOSS OR DAMAGE TO PROPERTY CAUSED BY the PRODUCT THAT ARE
OPERATED OR USED IN APPLICATION NOT INTENDED OR EXCLUDED BY INSTRUCTIONS, PRECAUTIONS, OR
WARNING CONTAINED IN MITSUBISHI'S USER, INSTRUCTION AND/OR SAFETY MANUALS, TECHNICAL
BULLETINS AND GUIDELINES FOR the PRODUCT.
("Prohibited Application")
Prohibited Applications include, but not limited to, the use of the PRODUCT in;
• Nuclear Power Plants and any other power plants operated by Power companies, and/or any other cases in which the
public could be affected if any problem or fault occurs in the PRODUCT.
• Railway companies or Public service purposes, and/or any other cases in which establishment of a special quality
assurance system is required by the Purchaser or End User.
• Aircraft or Aerospace, Medical applications, Train equipment, transport equipment such as Elevator and Escalator,
Incineration and Fuel devices, Vehicles, Manned transportation, Equipment for Recreation and Amusement, and
Safety devices, handling of Nuclear or Hazardous Materials or Chemicals, Mining and Drilling, and/or other
applications where there is a significant risk of injury to the public or property.
Notwithstanding the above restrictions, Mitsubishi may in its sole discretion, authorize use of the PRODUCT in one or
more of the Prohibited Applications, provided that the usage of the PRODUCT is limited only for the specific
applications agreed to by Mitsubishi and provided further that no special quality assurance or fail-safe, redundant or
other safety features which exceed the general specifications of the PRODUCTs are required. For details, please
contact the Mitsubishi representative in your region.

10
COMPLIANCE WITH EMC AND LOW VOLTAGE
DIRECTIVES
Method of ensuring compliance
To ensure that Mitsubishi programmable controllers maintain EMC and Low Voltage Directives when incorporated into other
machinery or equipment, certain measures may be necessary. Please refer to one of the following manuals.
• MELSEC iQ-R Module Configuration Manual
• Safety Guidelines (This manual is included with the base unit.)
The CE mark on the side of the programmable controller indicates compliance with EMC and Low Voltage Directives.
Additional measures
No additional measures are necessary for the compliance of this product with EMC and Low Voltage Directives.

11
CONTENTS
CONTENTS
SAFETY PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
CONDITIONS OF USE FOR THE PRODUCT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
COMPLIANCE WITH EMC AND LOW VOLTAGE DIRECTIVES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
RELEVANT MANUALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
TERMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
GENERIC TERMS AND ABBREVIATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
CHAPTER 1 PART NAMES 15
CHAPTER 2 SPECIFICATIONS 17
2.1 Performance Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.2 Cable Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
CHAPTER 3 FUNCTION LIST 19
CHAPTER 4 PROCEDURES BEFORE OPERATION 22
CHAPTER 5 SYSTEM CONFIGURATION 24
5.1 MELSECNET/H Network Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
CHAPTER 6 WIRING 26
6.1 Wiring Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
6.2 Wiring Products. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
CHAPTER 7 COMMUNICATION EXAMPLES 29
7.1 Cyclic Transmission Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
System configuration example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Setting in the control station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Setting in the normal stations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Checking the network status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Program example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
7.2 Transient Transmission Program. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
System configuration example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Setting in the control station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Setting in the normal stations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Checking the network status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Program example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
APPENDIX 42
Appendix 1 External Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
INDEX 44
REVISIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
WARRANTY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
TRADEMARKS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48

12
RELEVANT MANUALS
This manual does not include detailed information on the following:
• General specifications
• Applicable combinations of CPU modules and the other modules, and the number of mountable modules
• Installation
For details, refer to the following.
MELSEC iQ-R Module Configuration Manual
e-Manual refers to the Mitsubishi Electric FA electronic book manuals that can be browsed using a dedicated
tool.
e-Manual has the following features:
• Required information can be cross-searched in multiple manuals.
• Other manuals can be accessed from the links in the manual.
• The hardware specifications of each part can be found from the product figures.
• Pages that users often browse can be bookmarked.
• Sample programs can be copied to an engineering tool.
Manual name [manual number] Description Available form
MELSEC iQ-R MELSECNET/H Network Module
User's Manual (Startup)
[SH-082202ENG] (this manual)
System configuration, performance specifications, procedures before
operation, wiring, and communication examples of the MELSECNET/H
network module
Print book
e-Manual
PDF
MELSEC iQ-R MELSECNET/H Network Module
User's Manual (Application)
[SH-082204ENG]
Functions, parameter settings, programming, troubleshooting, and buffer
memory of the MELSECNET/H network module
Print book
e-Manual
PDF
MELSEC iQ-R Ethernet, CC-Link IE, and
MELSECNET/H Function Block Reference
[BCN-P5999-0381]
Specifications of the following MELSEC iQ-R module function blocks:
MELSEC iQ-R Ethernet equipped module function blocks, CC-Link IE TSN
module function blocks, CC-Link IE Controller Network module function
blocks, CC-Link IE Field Network module function blocks, and MELSECNET/H
network module function blocks
e-Manual
PDF
MELSEC iQ-R Programming Manual (Module
Dedicated Instructions)
[SH-081976ENG]
Dedicated instructions for the intelligent function modules e-Manual
PDF
GX Works3 Operating Manual
[SH-081215ENG]
System configuration, parameter settings, and online operations of GX Works3 e-Manual
PDF

13
TERMS
Unless otherwise specified, this manual uses the following terms.
Term Description
Baton pass A token to send data over a network
Buffer memory Memory in an intelligent function module for storing data such as setting values and monitored values.
When integrated into the CPU module, this memory refers to a memory for storing data such as setting values and
monitored values of the Ethernet function, and data used for data communication of the multiple CPU system
function.
Control system A system that controls a redundant system and performs network communications in a redundant system
Dedicated instruction An instruction that simplifies programming for using functions of intelligent function modules
Device A memory of a CPU module to store data. Devices such as X, Y, M, D, and others are provided depending on the
intended use.
Engineering tool A tool used for setting up programmable controllers, programming, debugging, and maintenance
Global label A label that is valid for all the program data when multiple program data are created in the project.
There are two types of global label: a module specific label (module label), which is generated automatically by GX
Works3, and an optional label, which can be created for any specified device.
Intelligent function module A module that has functions other than input and output, such as an A/D converter module and D/A converter
module
Link device A device (LB, LW, LX, LY, SB, or SW) in a MELSECNET/H network module
Link refresh Data transfer between a link device in a network module and a device in a CPU module.
Link refresh is performed in the END processing of the CPU module's sequence scan.
Link scan (link scan time) Time required for all the stations on the network to transmit data.
The link scan time depends on data volume and the number of transient transmission requests.
Logical channel Eight input channels that can be changed by using a program. The channel number can be specified from 1 to 64 by
changing the values in the link special register.
This channel number is used to receive only the messages selected on the receiving station when they have a lot of
information types. The sending station is equivalent to a broadcasting station, which sends messages to logical
channels. The receiving station is equivalent to a TV receiver in household, which receives the messages in the
required logical channels by switching channels.
MELSECNET/10 mode Mode that the MELSECNET/H network module operates on the MELSECNET/10 network.
MELSECNET/H extended mode A mode in which the maximum number of link points per station in MELSECNET/H mode is extended.
Values exceeding 2000 bytes to maximum 35840 bytes can be set.
Set this mode for a system that uses a large number of link points per station.
MELSECNET/H mode Mode that the MELSECNET/H network module operates on the MELSECNET/H network.
Module label A label that represents one of memory areas (I/O signals and buffer memory areas) specific to each module in a
given character string.
For the module used, GX Works3 automatically generates this label, which can be used as a global label.
Normal station A station that performs cyclic transmission and transient transmission with the control station and other normal
stations
Process CPU (redundant mode) A Process CPU operating in redundant mode.
A redundant system is configured with this CPU module. Process control function blocks and the online module
change function can be executed even in this mode.
Redundant system A system consisting of two systems that have same configuration (CPU module, power supply module, network
module, and other modules). Even after an error occurs in one of the two system, the other system takes over the
control of the entire system.
Relay station A station that includes two or more network modules. Data are passed through this station to stations on other
networks.
Standby system A backup system in a redundant system
System switching A function which switches the systems between the control system and the standby system to continue operation of
the redundant system when a failure or an error occurs in the control system

14
GENERIC TERMS AND ABBREVIATIONS
Unless otherwise specified, this manual uses the following generic terms and abbreviations.
Generic term/abbreviation Description
Network module A generic term for the following modules:
• Ethernet interface module
• A module on CC-Link IE TSN (the RJ71GN11-T2 and a module on a remote station)
• CC-Link IE Controller Network module
• A module on CC-Link IE Field Network (a master/local module, and a module on a remote I/O station, a remote
device station, and an intelligent device station)
• MELSECNET/H network module
• MELSECNET/10 network module
• RnENCPU (network part)

1 PART NAMES
15
1
1PART NAMES
This chapter describes the names of each part of the RJ71LP21-25.
*1 The LED is always off in offline mode.
No. Name Description
(1) RUN LED On: Normal operation
Off: Error (MELSEC iQ-R MELSECNET/H Network Module User's Manual (Application))
ERR LED*1 On or flashing: Error (MELSEC iQ-R MELSECNET/H Network Module User's Manual (Application))
Off: Normal operation
T PASS LED*1 On: Baton pass (state of connecting to the network)
Flashing: Testing
Off: Baton pass not executed (disconnection of the own station from the network)
D LINK LED*1 On: Data link (state of performing cyclic transmission)
Off: Data link not performed (disconnected)
25M LED On: Communicating at 25Mbps
Off: Communicating at 10Mbps
MNG LED*1 On: Operating as a control station or sub-control station
Off: Operating as a normal station
SD/RD LED On: Data being sent or received
Off: Data not sent nor received
L ERR LED On: Communication error
Any of the following has occurred.
• Cable failure or noise
• Before receiving data, the RJ71LP21-25 has received the next data and deleted the previous one. Or, hardware
failure has occurred in the RJ71LP21-25 receiving part.
• The number of bits whose value is one in the receive data in the frame is more than specified, or the receive data
is shorter than specified.
• Baton pass does not return to own station within the monitoring time.
• Data with an abnormal code has been received.
• Internal processing of send data is not performed at regular intervals.
• Failure has occurred in the forward loop line or reverse loop line; the power supply of the adjacent station to be
sent to the own station is turned off. Or, hardware failure has occurred in the sending station part of the loop.
Off: No communication error
(2) Dot matrix LED Indicates the station number set to the RJ71LP21-25 and the status of each test. (Page 16 Dot matrix LED
indication).
(3) Optical connector (IN
connector)
A connector to connect the optical fiber cable. Connect to OUT connector of another station.
(4) Optical connector (OUT
connector)
A connector to connect the optical fiber cable. Connect to IN connector of another station.
(5) Production information
marking
Indicates the production information (16 digits) of the module.
(1)
(3)
(2)
(4)
(5)

16 1 PART NAMES
Dot matrix LED indication
Displays the station number set to the RJ71LP21-25 and the status of each test.
Module operation mode Display
Online mode
Debug mode
Displays the station number currently set to the RJ71LP21-25.
• Control station, normal station: 1 to 64
• No parameter set: ""
Offline mode "" is displayed.
Forward loop test "MD3" is displayed. The operation mode is displayed during the execution of each test.
For the displayed content of each test result, refer to the following.
MELSEC iQ-R MELSECNET/H Network Module User's Manual
(Application)
Reverse loop test "MD4" is displayed.
Station-to-station test (executing
station)
"MD5" is displayed.
Station-to-station test (non-executing
station)
"MD6" is displayed.
Self-loopback test "MD7" is displayed.
Internal selfloopback test "MD8" is displayed.
Hardware test "MD9" is displayed.

2 SPECIFICATIONS
2.1 Performance Specifications 17
2
2SPECIFICATIONS
2.1 Performance Specifications
The following table lists the performance specifications of the RJ71LP21-25.
*1 The number of points for LY for a station set as the I/O master station is the sum of LY output to all the stations in the block.
Item Description
Maximum number of
link points per
network
LB 16384 points (MELSECNET/10 mode: 8192 points)
LW 16384 points (MELSECNET/10 mode: 8192 points)
LX 8192 points
LY 8192 points
Maximum number of
link points per
station*1
LB • MELSECNET/H mode, MELSECNET/10 mode
((LY+LB)8+(2LW))2000 bytes
• MELSECNET/H extended mode
((LY+LB)8+(2LW))35840 bytes
LW
LX
LY
Communication speed 25Mbps/10Mbps (MELSECNET/10 mode: 10Mbps)
Number of connected stations per network 64 stations (control station: 1, normal station: 63)
Connection cable Optical fiber cable
For details, refer to the following.
Page 18 Cable Specifications
Applicable connector 2-core optical connector plug
F06/F08 equivalent (JIS C5975/5977 compliant)
Overall cable distance 30km
Maximum station-to-station distance The maximum station-to-station distance varies depending on the optical fiber cable used.
For details, refer to the following.
Page 18 Cable Specifications
Maximum number of networks 239
Maximum number of groups 32 (MELSECNET/10 mode: 9)
Network topology Duplex loop
Communication method Token ring
Transient transmission capacity 1920 bytes maximum (MELSECNET/10 mode: 960 bytes maximum)
Number of occupied I/O points 32 points
Internal current consumption (5VDC) 0.48A
External dimensions Height 106mm (Base unit mounting side: 98mm)
Width 27.8mm
Depth 110mm
Weight 0.15kg

18 2 SPECIFICATIONS
2.2 Cable Specifications
2.2 Cable Specifications
The following table lists the specifications of optical fiber cables.
The types of optical fiber cables that can be used vary depending on the station-to-station distance.
Type Station-to-station distance Applicable connector
25Mbps 10Mbps
SI optical fiber cable
(Old type: A-2P-)
Type L 200m 500m F06/F08 equivalent (JIS
C5975/5977 compliant)
Type H 100m 300m
SI optical fiber cable 200m 500m
H-PCF optical fiber cable 400m 1000m
Broadband H-PCF optical fiber cable 1000m 1000m
QSI optical fiber cable/Broadband silica glass optical fiber cable 1000m 1000m