4. Troubleshooting (DeviceNet)
♦ Causes of Error |
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| Countermeasure | |
| Possible Cause | Examination Method | |||
| { Master unit | (1) Start | applicomIO | Console | Change the configuration. |
| configuration | application and check that the |
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| configuration has no | difference |
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| with the network condition. |
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(2)Check that the configuration data were written in flash.
(3)Check that the network load is within allowable range.
zFor details, refer to the section 4.1.3.6 EPSON RC+ Master Configuration.
{ Disconnected | (1) | Check that terminating resistors | Fix the problem. | |
terminating |
| are connected to both ends of the |
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resistors |
| network. | How to find the trouble | |
{ Cable | (2) | Measure resistance between signal | point: |
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disconnection |
| wires with communications power | Remove | the terminating |
{ Disconnected |
| supply OFF. | resistor on one end of the | |
connector | → Normal: 50 to 70 Ω | network. | The trouble | |
{Disconnected z Measuring point: Connection of the point is where resistance
signal wire | trouble unit | changes from 120 Ω. | ||
| z For detail, refer to the section |
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| 4.1.3.1 Connection Problem. | Connect | the | connectors |
{ Loose connector | Check for the connection of connectors | |||
{ Loose signal | and signal wires. | and signal wires again. | ||
wire | → The connectors and signal wires |
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| should be firmly connected. |
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| z Checkpoint: all nodes and all branch |
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| taps |
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| z For details, refer to the section |
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| 4.1.3.2 Loose Connector and Signal |
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| Wire. | Check the voltage of the | ||
{ Voltage drop of | Measure voltage of communications | |||
communications | power supply at the unit with a trouble. | power supply. |
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power supply | → Normal: 11V or more between V+ | Calculate | the | current |
| and V- | capacity of the cable and | ||
| z If the voltage is 11 to 14 V, the unit | add more communications | ||
| is a possible cause. Fix the problem | power supplies. |
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| on the unit. | Take | countermeasures | |
{ Noise | Check the noise intrusion via the | |||
(external cause) | following paths (1) to (3). | against noise. |
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| (1) Noise via DRAIN (FG) |
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| (2) Induced noise via communication |
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| cable |
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| (3) Communications power supply |
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| → For details, refer to the section |
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| 4.1.3.3 Noise Intrusion. | Replace the unit with a | ||
{ Broken unit | Replace the broken unit with a new | |||
| one. | new one. |
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| → Verify whether the problem is |
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| fixed. |
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z No cause is | Identify the trouble point by dividing |
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identified. | the network. |
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| → For details, refer to the section |
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| 4.1.3.4 Broken Unit Examination. |
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Fieldbus I/O Rev.6 | 93 |
