Epson RC620 Manual page 174

4. Troubleshooting (DeviceNet)
Countermeasure 2: Disconnect the shield wire to isolate it from the ground.
♦ Induced noise via communication cable
Separate the DeviceNet signal wire from the other wires (especially power wires).
Signal wire
PLC input/output wire
PLC power wire
Control circuit wire
Power wire
164
When noise intrudes the ground line due to a noise source such as an inverter installed
near the communications power supply, disconnect the shield wire of the
communication cable and isolate it from the ground to restrain noise intrusion.
Power Supply Tap
V+
CAN H
Shield (S)
CAN L
V-
V+ V- S
V+ V- FG
Communications
Power Supply
24 V DC
Light electrical cable
Communication cable
Control cable
Power cable
During site inspection, bypass the wire that is possibly affected by induced noise with
other cables and then lay the cables. Establish the communication under no induced
noise condition and verify whether an error occurs.
V+
CAN H
Shield (S)
DeviceNet cable
CAN L
V-
Disconnect here.
Ground 100 Ω or less.
* Separate the signal wire from the power wires 300 mm or more.
Suspended ducts
300 mm
or more
Conduit
300 mm
1
or more
Floor ducts
1 2
1
2
1 Signal wire
PLC input/output wire
2
2 Power wire
RC620 Option Fieldbus I/O Rev.8