748
Connections to Serial Communications Option Boards
Appendix F
Reducing Electrical Noise for External Wiring
Observe the following precautions when wiring communications cables, PLC power lines, and high-power
lines. When multi-conductor signal cable is being used, avoid using I/O wires and other control wires in the
same cable.
• If wiring racks are running in parallel, allow at least 300 mm between them.
• 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.
2-Wire and 4-Wire Connections
The transmission circuits for 2-wire and 4-wire connections are different, as shown in the following diagram.
Note
(1) Use the same transmission circuit (2-wire or 4-wire) for all nodes.
(2) Do not use 4-wire connections when the 2/4-wire switch on the Board is set to 2-wire.
Communications
cables
Low-current cables
PLC 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
PLC 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)
Option Board
2/4-wire switch
(DPDT)
Option Board
Not connected
Other Unit
Other Unit
Other Unit
Other Unit
Summary of Contents for CP1L-EL20DR-D
Page 3: ...CP1L EL20D CP1L EM30D CP1L EM40D CP1L EL EM CPU Unit Operation Manual Produced July 2017...
Page 4: ...iv...
Page 10: ...x...
Page 22: ...xxii...
Page 34: ...xxxiv Software Licenses and Copyrights 7...
Page 192: ...158 Trial Operation and Debugging Section 5 3...
Page 250: ...216 Automatic Clock Adjustment and Specifying Servers by Host Name Section 6 7...
Page 666: ...632 Trouble Shooting Section 11 7...
Page 696: ...662 Standard Models Appendix A...
Page 805: ...771 Connections to Serial Communications Option Boards Appendix F Connecting to Unit...
Page 806: ...772 Connections to Serial Communications Option Boards Appendix F...
Page 836: ...802 PLC Setup Appendix G...
Page 838: ...804 TCP Status Transitions Appendix H...
Page 840: ...806 Ethernet Network Parameters Appendix I...
Page 842: ...808 Buffer Configuration CP1L EL EM Appendix J...
Page 844: ...810 Ethernet Specifications Appendix K...
Page 851: ...Index 817 work words 118 write protection 447...
Page 852: ...818 Index...
Page 854: ...820 Revision History...
Page 855: ......