Mitsubishi Electric MELSEC iQ-R Series Quick Start Manual page 7

[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 a solderless terminal with an insulation sleeve for terminal block wiring. Note that up to two
solderless terminals can be connected per terminal block.
● 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 100 mm or more between them. Failure to do so may result in malfunction
due to noise.
● When an overcurrent caused by an error of an external device or a failure of a module flows for a long
time, it may cause smoke and fire. To prevent this, configure an external safety circuit, such as a fuse.
● 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.
● When disconnecting the communication cable or power cable from the module, do not pull the cable
by the cable part. For the cable connected to the terminal block, loosen the terminal screws. Pulling
the cable connected to the module may result in malfunction or damage to the module or cable.
● 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.
● Tighten the terminal block mounting screws, terminal screws, and module fixing screws within each
specified torque range. Undertightening of the terminal block mounting screws and terminal screws
can cause short circuit, fire, or malfunction. Overtightening of them can damage the screw and/or
module, resulting in drop, short circuit, or malfunction. Undertightening of the module fixing screws
can cause drop of the screw. Overtightening of them can damage the screw and/or module, resulting
in drop.
● 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.
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