Omron CJ1W-SCU22, Руководство по эксплуатации, Страница: 117 / 478

3-7
3 Installation and Wiring
CJ-series Serial Communications Units Operation Manual for NJ-series CPU Unit(W494)
3-2 Wiring
3
3-2-6 R
educing Electr
ical
Noise
f
or Exter
nal Wir
ing
Observe the following precautions for external wiring.
• When multi-conductor signal cable is used, avoid use of I/O wires and other control wires in the same
cable.
• If wiring racks are running in parallel, allow at least 300 mm between the racks.
• If you place the I/O wiring and power cables in the same duct, shield them from each other with
grounded steel sheet metal.
The transmission circuits for 2-wire and 4-wire connections are different, as shown in the following dia-
gram.
3-2-6 Reducing Electrical Noise for External Wiring
3-2-7 2-Wire and 4-Wire Connections
Communications
cables
Low-current cables
Power supply and
general control
circuit wiring
Power lines
300 mm min.
Ground to 100
Ω
or less.
Control cables
Power cables
300 mm min.
Communications
cables
Power supply and
general control
circuit wiring
Power lines
200 mm min.
Ground to 100
Ω
or less.
Steel sheet metal
Example of 4-Wire
Connections
Example of 2-Wire
Connections
2/4-wire switch
(DPDT)
Unit
2/4-wire switch
(DPDT)
Unit
Not connected
Other Unit
Other Unit Other Unit
Other Unit