Mitsubishi MELSEC-WS series, User Manual

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4
[Wiring Precautions]
WARNING

Shut off the external power supply (all phases) used in the system before wiring.
Failure to do so may result in electric shock or damage to the product.
The system could start up unexpectedly while you are connecting the devices.
CAUTION

Individually ground the GND wires of the MELSEC-WS safety controller with a ground resistance
of 100 Ω or less.
Failure to do so may result in electric shock or malfunction.

Check the rated voltage and terminal 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 a fire or
failure.

Tighten the terminal screw within the specified torque range.
Undertightening can cause short circuit, fire, or malfunction. Overtightening can damage the
screw and/or module, resulting in drop, short circuit, or malfunction.

Prevent foreign matter such as dust or wire chips from entering the module.
Such foreign matter can cause a fire, failure, or malfunction.

Mitsubishi MELSEC-WS safety controllers must be installed in control cabinets. Connect the main
power supply to the MELSEC-WS safety controller through a relay terminal block.
Wiring and replacement of an external power supply must be performed by maintenance
personnel who is familiar with protection against electric shock. (For wiring methods, refer to
Chapter 7.)

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.