50 modbus devices

[gdimaria]

Hi, I have to interrogate and command about fifty modbus devices, spread over different floors of a building. 

How many LMs would I need to optimize loads and how can I implement a single supervision interface for all equipment?

Any suggestion is welcome

Thanks


Peppe

[Daniel]

One LM would do but via two lines, one can have up to 31 devices. Do not expect this to work fast.

[gdimaria]

One LM would do but via two lines, one can have up to 31 devices.  Do not expect this to work fast.

the fact is that the project manager proposed a system consisting of an LM for supervision and n.4 LM on which to connect the various modbus devices. Is it achievable?

[Daniel]

Yes

[gdimaria]

Yes?

It would be nice to have some more guidance.
How can I view on an LM the modbus objects of the other 4?
Do I need to use a frame?
Or do I have to map all addresses to the main LM?
In short, can you tell me how you would do it?
Thank you

[admin]

Use one LM for visualization and exchange data with other LMs via KNX/IP. No extra configuration is needed for this but adjust filtering tables is recommended to lower the system load.
On Modbus side make sure that GND is connected between all devices and that bus topology is used.

[gdimaria]

ok thank you so much

Peppe

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Just a doubt: currently the LM "master" is in TP UART with KNX IP features on. The other LMs with modbus devices are also in TP UART with KNX IP feature off. Do you mean I have to activate it? Thanks again

[admin]

If several LMs are connected to the same TP line then IP features must only be enabled on one LM. Otherwise you should enable IP features on all LMs and it's recommended to enable encryption as well. If LM does not have TP connection then switch connection mode to IP routing.