This topic is to help you identifying error on your modbus setup if it does not work properly
Please check the following:
- Wiring:
- Daisy-chain wiring topology is the only one allowed. Do not use free topology scheme
- The polarity of the cable should be correct
| Wattsense box | Modbus device |
|---|---|
| A+ <–> | A+ |
| B- <–> | B- |
| GND <–> | GND |
-
Communication settings (i.e. Baudrate, parity, data bits, stop bits): They must be identical on each equipment.
-
Slave id: it should be unique for each device on the network.
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With several equipment on the network, one of them can be wrongly configured, please try the following steps:
- Isolate the bad device
- Disconnect the modbus network at wattsense box level (unplug the green connector)
- Connect the bad device directly to the box and try to communicate
- Once it works, add it back to the network (following recommendation #1)