Modbus driver for Hubitat

Hi Hubitat team and forum users.

I'm Mike from Canada (Qc) and I do HA since X10 :slight_smile:
With years, I managed to use a lot of modbus devices (RTU & TCP), mostly controlled by 2 industrial plc's (Semaphore) and other slaves/masters.
I'm kind of an old fashioned guy, so don't really like my home controlled through cloud and/or voice assistants (you know them all for sure). my setting is principally wired. I'm really not into jabbering to my lights...
I just purchased Hubitat (not yet received...) because I purchased some Lutron Caseta switches and hub and I saw some reviews saying that Hubitat and Lutron Caseta can work together.

I don't need obligatory to control (all) my modbus devices with Hubitat but this solution could be nice. I tested a lot of software solutions (Jeedom, Homeseer, etc) to integrate modbus devices but I want also to separate security functions, control functions (solar, geothermal, electricity metering) and living functions (lights, music, confort) without going absolutely all-in-one.

So my question: do you have in your working boxes a (future) modbus driver able to connect modbus devices to Hubitat ? If not, is it possible to build it without going crazy ? Is It feasible on our side (what kind of programming) ? Or should I just stick on my Lutron and some Z-wave units ?

I know that modbus is not really security-minded, but I think that a wired modbus ring running into a local (separated) network is probably safer than any wireless connected cloud device. I'm maybe mistaken but I don't think that a random guy will go into my garden to cut some wires and wireshark a man-In-the-middle attack to my modbus devices... A unknown attacker from a far country will probably try to attack poorly protected IOT cams through internet (remember Mirai). Am I wrong ?

Last but not least, excuse my broken english, I'm mostly french speaking.
Btw, I'm an IT guy, so feel free to talk technical with me.
Mike

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FYI, you will need the Lutron Caseta Bridge Pro (L-BDGPRO2-WH) to use Caseta dimmers/switches with Hubitat.

I know nothing of modbus integration, so I can't address that, but there are plenty of more knowledgeable people here who can. I just wanted to clarify what you'll need to use your Caseta dimmers with Hubitat.

Edit - Welcome. This is a very nice home automation platform with a great community.

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Welcome to Hubitat.

I have never heard of anyone using ModbusTCP (or Modbus Serial) for home automation with Hubitat (or SmartThings.) If you want to integrate the two systems, I believe you may need to use a man-in-the-middle bridge device, like a Raspberry Pi (or similar), running something that can be used to talk to both systems. A quick search shows a ModbusTCP client for Node Red exists. There are quite a few users that have implemented Node Red as a means to integrate Hubitat (via the MakerAPI and Events webSocket) with other systems. I hope this at least gives you some ideas of what is possible.

Again, welcome to Hubitat!

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Hi and welcome.

This could/would be true for WiFi, but just so you understand a ZigBee or z-wave + wireless device is only connected to the hub and not to the cloud so if all you contacts were these you would be OK :slight_smile:

Oddly enough my friend uses it with his DIY stuff.
But in fairness we come from industrial automation.

That stuff is straight out of the dark ages.
:stuck_out_tongue_winking_eye:

As an industrial automation professional myself, I use modbus all the time - both serial and TCP.

Anyway, if I were going to integrate a modbus device with Hubitat I would either:

  1. If I needed low latency / fast response - Write a custom driver for Hubitat
    or
  2. If speed wasn't my main concern - Use Node-Red, as it has a modbus node type ( node-red-contrib-modbus - Node-RED ). Then push/pull the data from Hubitat via MakerAPI. Slower, but 1000x simpler than making/maintaining a custom driver.

I am a little biased, though. When I first setup Node-Red I was pulling/pushing data into Hubitat in <5 minutes (including creating the Node-Red docker container). While I've written a number of Hubitat device drivers, I can't say I could do one as fast as pushing in data via Node-Red. :wink:

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I plan on buying a new house in about 8 year. Can you write a driver in that time? :grin::rofl:

Because my current house I use zigbee and Z-wave. And in my next house I plan on doing everything over cables. I really really hate wireless stuff. That's just me :upside_down_face:

Hard-wired does work great. I have a lot of Cat5 cabling in my house. It's all great until lightning strikes in the nearby area. I lost network ports on multiple devices and completely fried a few network switches. As you might surmise, none of my wireless devices were impacted at all! :wink:

So, you say "Yea, but what are the odds of a lightning strike nearby?" I thought so as well until it happened a second time ~2 years later. :frowning_face:

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The risk is higher along the Gulf coast, but especially in Florida.

I have two whole house surge protectors, and additional surge protectors on all major appliance circuits.

Nothing will protect against a direct lightning strike, but I hope I'll be protected against surges caused by distant strikes.

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Hi Jason,
thank you for your reply. I'll probably stick to Node-Red. My plc are doing their jobs (controlling) and I'll retrieve data from the plc's and will send them slowly to Hubitat. I need to do that because I'm always very short in memory with my plc and I use it mainly for coding the rules, leaving a small amount of memory for display. For now I built some html pages with the data and upload them regularly. And I have mostly no need to change those settings, I have a geothermal unit, the thermostat has one setting: 22 celsius all the time. Heating in the winter, Cooling in the summer.