Chapter 10 PLC Installation, Mounting, Wiring

(7)Wiring to the unit terminals

Wiring for the power supply

Use a 2 mm2 cable and twist it. Leave a distance of 100 mm or more from the signal cable and 200 mm or more

Shield insulation from the power line. transformer

AC power supply

NF

Connection of a noise filter is recommended.

Ground wiring

Use a cable 2 mm2 or more for the wiring.

Class D grounding

Expansion cable

Always segregate power line, I/O signal and power supply cable

I/O signal cable

Leave a distance of at least 200 mm from the power line and do not run the wire next to the power cable.

Metal plate

 

Outer hull (Cabinet)

Perform class D grounding

 

Perform class D grounding

Figure 10.9 Example of wiring

(8)Wiring to the analog I/O terminals

Do not apply the voltage that exceeds the rated input voltage to the analog input terminals. In addition, do not allow the current that exceeds the rated input current to flow into the analog input terminals. If a power supply that is different from the specified power supply is connected, the product may be damaged or burned out.

For the channels that do not use the analog input terminals, be sure to short-circuit the analog input terminals before using such channels.

For the external wiring to the analog I/O terminals, use a shielded cable and make routing different from other power lines with different voltages and signal lines. In addition, ground one end of the shield cable. However, grounding both ends or open ends may have better effect than grounding one end of the shield cable, depending on the noise environment in which the equipment is used. Use the appropriate grounding method accordingly.

Place AC power supply lines, signal lines and data lines in separate pipes.

Wire signal lines and data lines as close as possible to a grounded surface such as a cabinet and metal bar.

10-8

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Hitachi NJI-350B manual Wiring to the unit terminals, 10-8