
4. Troubleshooting (DeviceNet)
♦Process Flowchart
Check for cable laying.
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Check that |
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terminating resistors |
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are connected. | (Add terminating resistors.) |
Normal
Turn OFF communications power supply.
Measure resistance | Out of 50 to 70 Ω (Error) |
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with tester. |
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50 to 70 Ω |
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| Normal |
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| Resistance: over 70 Ω | No |
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| Yes |
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| Under 10 Ω |
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See 4.1.3.2. |
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| Resistance: under 50 Ω |
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| Remove one terminating |
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| resistor on either side. |
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| 10 to 50 Ω |
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| Check for |
| connection |
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| Check | for short | ||||
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| Measure | with terminating resistors | circuit | between | ||||||
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| Approx. | and branch taps. |
| signal wires. | ||||||||||
| 120 | Ω | resistance at | (1) Three |
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| connectors and |
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| branch taps with | terminating resistors | between signal | |||||||
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| tester. | (2) Wrong |
| terminating | wires |
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| resistors, etc. |
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Other
Find the trouble point.
(1)Unconnected or loose connector
(2)Cable disconnection, etc.
Fieldbus I/O Rev.6 | 99 |