● Individually ground the FG terminal of the programmable controller with a ground resistance of 100
ohms or less. Failure to do so may result in electric shock or malfunction.
● Tighten any unused terminal screws within the specified torque range. Undertightening can cause a
short circuit due to contact with a solderless terminal.
● Use applicable solderless terminals and tighten them within the specified torque range. If any spade
solderless terminal is used, it may be disconnected when a terminal block screw comes loose,
resulting in failure.
● 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
● Tighten the terminal block screws 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, fire, 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.
● 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
● 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.
● 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.
● When an overcurrent caused by an error of an external device or a failure of the programmable
controller flows for a long time, it may cause smoke and fire. To prevent this, configure an external
safety circuit, such as a fuse.
● Mitsubishi programmable controllers must be installed in control panels. Wiring and replacement of a
module must be performed by qualified maintenance personnel with knowledge of protection against
electric shock. For wiring methods, refer to "INSTALLATION AND WIRING" in this manual.