5500NAC/SHAC acting as Modbus/TCP server (i.e. slave)

Hi Folks,

I have a need to have a BMS PLC able to see all the C-Bus group levels and change them from time to time via Modbus.

The 5500NAC/SHAC has lots of documentation for the device acting as a Modbus master (i.e. client) and the profile system that supports that, however I've not seen anything about it acting as a Modbus slave (i.e. server).

Has anyone else tried to do this before and found a solution?

From a previous thread I found the link to Logic Machine (who built the 5500NAC/SHAC for =SE=) and their forums and found the following as an example of doing exactly what I want with KNX:

https://openrb.com/lm-as-modbus-tcp-slave/

Before I jump into porting this for C-Bus support instead of KNX support (and they are conceptually very similar - I've used both over many years) I just wanted to make sure I wasn't reinventing the wheel.

If no one else has solved this and I use the code above as the basis for a Modbus/TCP server (i.e. slave) I'll post the code here to share with the group.

-Kelvin

 

Bringing up an old thread here.
Did you ever succeed with this code?
I have a (SMA data manager) acting as a master/client and communicating with pv and battery inverters (slaves) on an off-grid property situation and would like to send/poll/read 1 x register (Battery state of charge SOC).
For obvious reasons this would be a very useful byte of data to help cbus manage both self consumption and night time energy use.
Ash

 

Ive a working port of this if either of you are interested. I will be keen to test it out on a few sites

 

Hi Dasman,

Great stuff getting an implementation of this done.
I never got to this myself but would be super keen to help test any implementation you have. Are you in a position that you could post the code as an attachment to this discussion thread? If not let me know and we’ll find a way to do some sort of direct message.

Cheers, Kelvin

 

Hi Kelvin,

Apologies for the delay, please see the attached zip file, this includes everything I have put together for this. Let me know how you go!