Modbus rtu over zigbee to HA

Third party integrations
1

Hi!

I’m planning to get 3 units of ventilation system that talk Modbus RTU. I need your advice on how to wirelessly connect them to HA.

My current setup:

  • Turris Omnia router running HA 0.91.4. Extensible with USB and mini-PCIe.
  • CC2531 USB module with zigbee2mqtt for a couple of Xiaomi sensors

Planned hardware:

  • Serial over mini-PCIe Zigbee module from https://whitebream.com/xbee
  • Probably some Zigbee lightbulbs
  • The 3 modbus rtu devices in question

My goals are:

  • Wireless connection (it’s not possible to stretch a wire all way long for cosmetic reasons)
  • Prefer Zigbee over Wi-Fi (I like the idea of mesh networks and plan to extend my home zigbee network in the future)
  • Medium to low cost (i.e. avoid $1K enterprise hubs)
  • Keep it as much transparent as possible (i.e. keep the modbus where applicable and don’t invent modbus2myowncustom converters if possible)
  • Keep a device count to minimum (every new device is a single point of failure)

I tried to investigate the topic myself, but couldn’t come up with any good solution.

2

Hi Denis,

I am working on a similar setup with FHEM and found this: Zigbee Smart Building - Astrel
I am not affiliated with them, just an end-user like you. I am still exploring and expect to implement eventually next summer.

Good luck.
Paul

3

Dear Paul,

How did you end up implementing it?
I have 2 separate modbus RTU’s that I would like to read out.
Especially interested in the hardware side.
I’m currently considering a simple usb to RS485 cable.:
image

I think this looks promising too.

Best regards.