M340 and TeSys T Modbus

Hi,

I create project where use PLC M340 and I need to communicate with TeSys T motor controller by Modbus RTU. In this project I have also ethernet module NOC0401 where I've add some modbus TCP devices and it works excellent. But to this module I can also add TeSys T with modbus RTU. I can set every parameter for RTU but NOC0401 also automatically assign IP address to RTU devices. I don't know if it will be work if I connect RTU devices to NOC0401 module which I configured it.
In attachment you can see configuration of modbus serial devices into NOC0401 ethernet module.

Can anybody help me if I can use it this way ?

The NOC0401 is Modbus TCP, it cannot communicate with a Modbus RTU slave without a Modbus TCP to RTU gateway, unless i am misunderstanding your question ?

you understood my question very well, just wondering why I can add and configure modbus RTU devices (TeSys T) in this NOC0401 module ? When I add some devices to this module, I can set if this is serial or TCP modbus...Screenshot in attach.

I am a little confused about this

grz3chubak said:

you understood my question very well, just wondering why I can add and configure modbus RTU devices (TeSys T) in this NOC0401 module ? When I add some devices to this module, I can set if this is serial or TCP modbus...Screenshot in attach.

I am a little confused about this

Click to expand...

I'm confused too ! I have no idea why it would do that. Have you got the correct DTM ?

For Modbus RTU you would need a NOM module, the NOC0401 quite clearly states its ethernet only in the manual:

Overview

The Ethernet communication module serves as the interface between a M340 PLC and other
Ethernet network devices by means of either the EtherNet/IP or the Modbus TCP communication
protocol

Yes, I have the newest DTM from Schneider site.
My M340 has Modbus RTU so I don't need any extension module, I only should use Read_var function which I didn't want to do but I don't think I have a choice

grz3chubak said:

Yes, I have the newest DTM from Schneider site.
My M340 has Modbus RTU so I don't need any extension module, I only should use Read_var function which I didn't want to do but I don't think I have a choice

Click to expand...

You could put a gateway on the serial devices and still use the NOC, Schneider's own EGX (Link150) will do the job fine.

tragically1969 said:

You could put a gateway on the serial devices and still use the NOC, Schneider's own EGX (Link150) will do the job fine.

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I was just about to say this. Isnt that the reason why you can place the modbus rtu version dtm in the dtm browser? Then the device ip must all be the same as the gateway but with different unit id?
Just thinking out loud here

chud said:

I was just about to say this. Isnt that the reason why you can place the modbus rtu version dtm in the dtm browser? Then the device ip must all be the same as the gateway but with different unit id?
Just thinking out loud here

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I did wonder that but it's weird it lets you set it s Modbus SL as its effectively Modbus TCP, unless it needs to know its downstream of a gateway so it can handle timeouts etc.

tragically1969 said:

I did wonder that but it's weird it lets you set it s Modbus SL as its effectively Modbus TCP, unless it needs to know its downstream of a gateway so it can handle timeouts etc.

Click to expand...

Isn't EGX150 Modbus RTU over TCP gateway. So slave addresses is needed for communications.

Lare said:

Isn't EGX150 Modbus RTU over TCP gateway. So slave addresses is needed for communications.

Click to expand...

Yes it is