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Wiring Section 5-3
Note Use surge suppressors and diodes with the following specifications.
External Wiring Observe the following precautions for external wiring.
• When multi-conductor signal cable is being used, avoid combining I/O
wires and other control wires in the same cable.
• If wiring racks are parallel, allow at least 300 mm (12 inches) between the
racks.
If the I/O wiring and power cables must be placed in the same duct, they must
be shielded from each other using grounded steel sheet metal.
Surge suppressor specifications Diode specifications
Resistor: 50 Ω
Capacitor: 0.47 µF
Voltage: 200 V
Breakdown voltage: 3 times load voltage min.
Mean rectification current: 1 A
PLC I/O wiring
PLC power supply and
general control circuit wiring
Power lines
Ground to 100 Ω or less
Low-current cables
Control cables
Control cables
300 mm min.
300 mm min.
PLC I/O wiring
PLC power supply
and general
control wiring
Power lines
Steel sheet metal
Ground to 100 Ω or less
200 mm min.