Mitsubishi Electric MELSEC iQ-R Series User manual

MELSEC iQ-R Serial Communication Module
User's Manual (Application)
-RJ71C24
-RJ71C24-R2
-RJ71C24-R4

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 for the programmable
controller system, refer to the user's manual for the module used and 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/reserve 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 manuals relevant to the
network. 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 do not 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 may cause malfunction or failure of the module.
●When changing the operating status of the CPU module from external devices (such as remote RUN/
STOP functions), select "Do Not Open in Program" for "Open Method Setting" in the module
parameters. If "Open in Program" is selected, an execution of remote STOP causes the
communication line to close. Consequently, the CPU module cannot reopen the communication line,
and the external device cannot execute the remote RUN.

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 general specifications written in Safety
Guidelines included in 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 memory card slot. Check that it is inserted
completely. Poor contact may cause malfunction.
●Securely insert an extended SRAM cassette into the cassette connector of a 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, or connector. Doing so may 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 the included terminal cover to the module before turning it on 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 cable may swing or inadvertently be pulled,
resulting in damage to the module or cables or malfunction due to poor contact. 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]
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.
WARNING
●Do not touch any terminal while power is on. Doing so will cause electric shock or malfunction.
●Correctly connect the battery connector. Do not charge, disassemble, heat, short-circuit, solder, or
throw the battery into the fire. Also, do not expose it to liquid or strong shock. Doing so will cause the
battery to produce heat, explode, ignite, or leak, resulting in injury or fire.
●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.

7
[Startup and Maintenance Precautions]
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.
●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 mount/remove the module to/from the base unit, and the
terminal block to/from the module, and do not insert/remove the extended SRAM cassette to/from the
CPU module more than 50 times (IEC 61131-2 compliant) respectively. Exceeding the limit may cause
malfunction.
●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. Doing so may
cause malfunction or failure of the module.
●Do not drop or apply shock to the battery to be installed in the module. Doing so may damage the
battery, causing the battery fluid to leak inside the battery. If the battery is dropped or any shock is
applied to it, dispose of it without using.
●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.

8
[Startup and Maintenance Precautions]
[Operation Precautions]
[Disposal Precautions]
[Transportation Precautions]
CAUTION
●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.
●Do not power OFF the programmable controller or do not reset the CPU module while the setting
values in the buffer memory are being written to the flash ROM in the module. 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 may cause malfunction or
failure of the module.
CAUTION
●When disposing of this product, treat it as industrial waste.
●When disposing of batteries, separate them from other wastes according to the local regulations. For
details on battery regulations in EU member states, refer to the MELSEC iQ-R Module Configuration
Manual.
CAUTION
●When transporting lithium batteries, follow the transportation regulations. For details on the regulated
models, refer to the MELSEC iQ-R Module Configuration Manual.
●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.