Mitsubishi MELSEC L Series User Manual page 8

When using the MELSEC-L series serial communication module
[Design Precautions]
• For the operation status of each station at communication error in each station, refer to the
respective manual for each station.
The communication error may result in an accident due to incorrect output or malfunction.
• When connecting a peripheral with the CPU module or connecting an external device, such as a
personal computer, with an 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 or operating status change) of a
running programmable controller, read the relevant manuals carefully and ensure that the
operation is safe before proceeding.
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 write any data to the "system area" of the buffer memory in the intelligent function
module.
Also, do not use any "use prohibited" signals as an output signal to an intelligent function
module from the CPU module.
Writing data into the "system area" or outputting a signal for "use prohibited" may cause a
programmable controller system malfunction.
[Design Precautions]
• Do not install the control lines or communication cables together with the main circuit lines or
power cables.
Keep a distance of 100mm between them.
Failure to do so may result in malfunction due to noise.
[Installation Precautions]
• Shut off the external power supply (all phases) used in the system before mounting or removing
a module. Failure to do so may result in electric shock or cause the module to fail or
malfunction.
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When using the MELSEC-L series serial communication module
WARNING
!
CAUTION
!
WARNING
!
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