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5 network configuration and specifications – Epson EM07ZS1647F User Manual

Page 117

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4. Troubleshooting (DeviceNet)

(2) Separate each slave from the network

Check for each slave. The trouble point is where error condition changes into normal
condition.

PLC

Slave

Branch Tap

Communications

Power Supply

Terminating

Resistor

Branch Tap

Slave

Slave

Master

Slave

Second First

Separate slaves one by one from
the network.

Terminating

Resistor

4.1.3.5 Network Configuration and Specifications

(1) Maximum Network Length and Drop Line Length

Check that the cables used on the network meet the following specifications.

Type Baud

Rate

Max. Network

Length

Drop Line

Length

Total Drop

Line Length

500 kbps

100 m

39 m

250 kbps

250 m

78 m

Thick Cable

125 kbps

500 m

156 m

500 kbps

100 m

39 m

250 kbps

100 m

78 m

Thin Cable

125 kbps

100 m

6 m

156 m

(2) Terminating Resistor

Ensure that two terminating resistors are connected to both ends of the network (trunk
line). The terminating resistor should be 121

Ω 1/4 W.

(3) Cable and Branch Tap

The cables and branch taps should meet the DeviceNet specifications.

(4) Communications Power Supply

The communications power supply should be dedicated to DeviceNet.
Do not share power source with the communications power supply and I/O device. *

* Noise due to load on/off may affect DeviceNet communications via the

communications power supply.
(The noise causes remote I/O communication error, Busoff detection, and broken
unit.)

Fieldbus I/O Rev.6

105