Hi Chris,

I don’t know exactly - first time using ModBus :-)… I have used the Java ModBus 
Server (ModbusPal) for testing and there I can create multiple slaves listening 
on the same port. And also for example in WinCC Unified I can also set a 
slaveId when I setup a ModBus TCP connection to a modbus device… so, I thought 
“this is missing in PLC4X”...

Regards,
Andreas

> On 12.08.2021, at 12:10, Christofer Dutz <[email protected]> wrote:
> 
> Hi Andreas,
> 
> I think the main reason is (as far as I understood it) that the slave id is 
> particularly needed for modbus RTU over RS485 as here multiple devices are 
> listening to the same connection. For this you identify the desired host with 
> the slave id. In TCP it's always a one-to-one connection, so the slave id is 
> pretty much ignored (As I said ... as far as I know)
> 
> Chris
> 
> -----Ursprüngliche Nachricht-----
> Von: Andreas Vogler <[email protected]> 
> Gesendet: Donnerstag, 12. August 2021 11:18
> An: [email protected]
> Betreff: ModBus set slaveId...
> 
> Hi again,
> I found a thread regarding how to set the slaveId here: [email protected] 
> <mailto:[email protected]> But when I try to use it 
> (modbus://localhost:502?slaveId=2 <modbus://localhost:502?slaveId=2>) it does 
> not make any difference. It always uses slave 1… Best regards, Andreas
> 

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