8. Trouble Shooting
The communication status LEDs can be used to verify correct operation of the Modbus module. During normal operation, the LED indicators flash as follows:
•RXD LED: Flashes when the Modbus master sends a message to the EX10
•TXD LED: Flashes when that specific
This LED is only relevant to the module on which it is being viewed, regardless of how many slaves are on the network. It indicates that the module has received a message that is uniquely addressed to it, and the
If the LED indicators are not flashing, check the following:
1)Wiring connections
2)Resistance at terminals
3)Baud rate setting
4)Station Number
5)HAD Switch
6)Parity selection
7)Modbus master is using standard Modbus RTU format
If the LED indicators are on solid:
The polarity has been reversed on the network wiring. For example, the “A” terminals are wired to the “B” lines, the “+” terminals are wired to the
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