4. Troubleshooting (DeviceNet)

Process Flowchart

Check for cable laying.

 

 

 

 

 

 

 

 

 

 

 

 

Check that

 

Problem exists.

 

terminating resistors

 

 

are connected.

(Add terminating resistors.)

Normal

Turn OFF communications power supply.

Measure resistance

Out of 50 to 70 Ω (Error)

 

 

 

 

 

 

 

with tester.

 

 

 

 

 

 

 

 

 

 

 

 

 

50 to 70 Ω

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Normal

 

 

 

Resistance: over 70 Ω

No

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Yes

 

 

 

 

Under 10 Ω

 

 

See 4.1.3.2.

 

 

 

 

 

Resistance: under 50 Ω

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Remove one terminating

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

resistor on either side.

 

 

10 to 50 Ω

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Check for

 

connection

 

 

 

 

 

 

 

 

 

 

 

 

 

Check

for short

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Measure

with terminating resistors

circuit

between

 

 

Approx.

and branch taps.

 

signal wires.

 

120

resistance at

(1) Three

 

or

more

 

 

 

 

 

 

 

 

 

connectors and

 

Short

 

circuit

 

 

 

 

 

 

 

 

 

 

 

 

 

 

branch taps with

terminating resistors

between signal

 

 

 

 

 

 

tester.

(2) Wrong

 

terminating

wires

 

 

 

 

 

 

 

 

 

 

 

resistors, etc.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Other

Find the trouble point.

(1)Unconnected or loose connector

(2)Cable disconnection, etc.

Fieldbus I/O Rev.6

99

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Image 111
Epson EM07ZS1647F manual Check for cable laying Check that