Important Wiring Considerations; Internal Circuitry - Omron CJ1W-CT021 Operation Manual

Wiring
2-3-3

Important Wiring Considerations

2-3-4

Internal Circuitry

Digital Input Circuitry
36
Refer to Appendix A "Using Terminal Block Units with Screw-terminals" for infor-
mation on the numbering of the screw-terminals. You need this information in case
you want to connect the external signals via Terminal Block Units to the High-
speed Counter Unit.
Use the following guidelines when planning the system wiring of the Unit:
• Disconnect the power to the PLC-system before wiring the Unit.
• Make sure the PLC-system is properly grounded.
• Use shielded, twisted pair cables and ground the shield when wiring the Coun-
ter Inputs (A, B, Z) and the Digital Inputs. When grounding the shield at the side
of the Unit, use the same reference as the ground terminal of the PLC-Power
Supply is connected to.
• Make the wiring for the Counter Inputs A, B and Z as short as possible and do
not route the wires parallel to lines that produce a lot of noise, such as high-volt-
age power lines.
• Try to use a separate stabilised Power Supply for the High-speed Counter Unit
and another Power Supply for other Units.
Digital Input I0: Digital Input I1:
24 V
B5 (24 V)
0 V
A5 (0 V)
Section 2-3
B6 (24 V)
A6 (0 V)