How can I connect to the multiple Slave stations by Modbus RTU protocol?

Last modified by Jett on 2025/04/02 11:15

Usually when using the Modbus protocol, customers will use more than one slave station, and each slave station has a different station number. The HMI can change the default slave station to be read by switching the default station number through a special register.

13 HMI Internal Registers - Wecon

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Or customer can set the PLC station in the address choose.

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Using the ie/ig series HMI, when the user want to connect devices by RTU, maybe facing with the following question:

1. The all addresses are right format, if just connect to the one Slave, it didn't timeout at all;

2. But when connect to the more than one Slave, the HMI will start to timeout;

So the solution is below according to this situation:

1. Make sure your software version is updated to the latest; 

Jump To

2. Add a Delay Time 5ms here;

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