[DESIGN PRECAUTIONS]
WARNING
● Make sure to set up the following safety circuits outside the PLC to ensure safe system operation
even during external power supply problems or PLC failure. Otherwise, malfunctions may cause
serious accidents.
(1) Note that when the CPU module detects an error, such as a watchdog timer error, during self-
diagnosis, all outputs are turned off. Also, when an error that cannot be detected by the CPU
module occurs in an input/output control block, output control may be disabled. External circuits
and mechanisms should be designed to ensure safe machinery operation in such a case.
● Construct an interlock circuit in the program so that the whole system always operates on the safe
side before executing the control (for data change) of the PLC in operation. Read the manual
thoroughly and ensure complete safety before executing other controls (for program change,
parameter change, forcible output and operation status change) of the PLC in operation. Otherwise,
the machine may be damaged and accidents may occur due to erroneous operations.
● For the operating status of each station after a communication failure of the network, refer to relevant
manuals for the network. Incorrect output or malfunction may result in an accident.
● When executing control (data change) to a running other station programmable controller by
connecting the external device to the SLMP compatible device, configure interlock circuits in the
program of the other station programmable controller to ensure that the entire system operates safely
at any times.
For other controls to a running other station programmable controller (such as program modification or
operating status change), read relevant manuals carefully and ensure the safety before the operation.
Especially, in the case of a control from an external device to a remote other station programmable
controller, immediate action cannot be taken for a problem on the programmable controller due to
communication failure. Determine the handling method as a system when communication failure
occurs along with configuration of interlock circuit on other station PLC program, by considering
external equipment and other station PLC.
● Do not write any data into the "system area" or "write protect area" of the buffer memory in the SLMP
compatible device or intelligent function module. Also, do not output (ON) any "use prohibited" signals
among the signals which are output to the SLMP compatible device and intelligent function device.
Executing data writing to the "system area" or "write protect area", or outputting "use prohibited"
signals may cause malfunction of the programmable controller alarm.
● 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.
[WIRING PRECAUTIONS]
WARNING
● Make sure to cut off all phases of the power supply externally before attempting installation or wiring
work. Failure to do so may cause electric shock or damage to the product.
● Make sure to attach the terminal cover, provided as an accessory, before turning on the power or
initiating operation after installation or wiring work. Failure to do so may cause electric shock.
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