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

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Image 113
Epson EM07ZS1647F manual Noise Intrusion, Ground of FG Drain wire, Countermeasure 1 Disconnect the wire between V- and FG