
4. Troubleshooting (DeviceNet)
4.1.3.3 Noise Intrusion
Verify how an error occurrence condition changes while taking the following countermeasures.
♦Ground of FG (DRAIN) wire
Normal Grounding: Ground the DeviceNet network at only one point.
Power Supply Tap
V+ | V+ |
|
CAN H | CAN H |
|
Shield (S) | Shield (S) | DeviceNet cable |
CAN L | CAN L |
|
V- | V- |
|
V+ V- S
V+ V- FG
Ground 100 Ω or less.
Communications
power supply
24 V DC
Countermeasure 1: Disconnect the wire between V- and FG.
Disconnect the wire between V- and FG when you cannot ground the FG wire.
Power Supply Tap
V+ | V+ |
|
CAN H | CAN H |
|
Shield (S) | Shield (S) | DeviceNet cable |
CAN L | CAN L |
|
V- | V- |
|
V+ V- S
Disconnect here.
V+ V- FG
Ground 100 Ω or less.
Communications
Power Supply
24 V DC
Fieldbus I/O Rev.6 | 101 |