Verify wiring on KilnScout RS485 hub network
When there is a lose of communication or intermittent communication of hubs, identify if there are open or shorted communication wires in the RS-485 network.
Step-by-step guide
Ensure the RS-485 adapter is completely disconnected from the network or erroneous measurements may result.
STEPS |
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| 1 | Disconnect the RS-485 to RS-232 adapter at the PC to isolate the communication cable. |  RS-485 adapter |
| 2 | Identify the last hub(s) on the RS-485 network. If there is a hub at each end, identify both. |
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| 3 | Place the jumper on 'term enable' (terminating resistor) on the JP1 terminal on the identified hub(s). This terminating resistor value is 150 ohms. |  Hub card terminating jumper location
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| 4 | At the RS-485 adapter, measure the resistance between T/R+ and the T/R-. |
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| 5 | If there is one hub with a terminating jumper, the measurement should be 150 ohms. If there are two hubs, the measurement should be 75 ohms. |
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| 6 | If the measured resistance is not within 10 ohms of the specified value, trace the communication line to determine at which point the wiring should be corrected. |
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