MODBUS and central heating?

[ericmark]

I thought the MODBUS protocol was to work with SCARTA and PLC's but have seen it a few times on wall thermostats, this thermostat

seems to be causing the asking of questions again and again, seems called the KKMOON HC-T010-EWF and has a MODBUS and NTC sensor, in the main it seems people ignore the MODBUS and NTC sensor options. I would guess really designed for electric under floor heating I did find

The HC-T010-EWF series range has been developed to control electric underfloor heating systems. These units are designed for use in commercial, industrial, civil and domestic properties.

【Voice Control】Compatible with Amazon Echo, Google Home, Tmall Genie, IFTTT. For example, you can say, "Alexa, set bedroom to 25 degree."
【Accurate Temperature】Internal sensor floor sensor, perceptive ambient temperature and the floor's temperature. 0.5℃ Accuracy keeps temperature within the level you set.
【Weekly Programmable】The thermostat supports different temperature setting accordingly with 6 time-modes daily.
【Group Control & Smart Scene】Create thermostat group to centralized control. No limit to add thermostats and support Smart Scene.
【Easy Operation】Touch Screen display with backlight is easy to read even in the dark. Easy Ul interface, convenient operation creates convenient life.
【Synchronize Design】All setting languages synchronize your time zone, address and language.
【Memory Function】No need to worry about power failure, data memory when power is off.

It seems people buy them as a cheap way to connect to Amazon Echo etc. With 4 screw terminals I can't see why any one would ask questions on how to connect, so I assume people think it connects to boiler with MODBUS, seem to remember the Myson Ivector fan assisted radiators do connect to building management systems so they can heat and cool, and with the increased use of heat pumps there seems to be no reason not to have the same units both heat and cool, but that does not work with under floor heating so seems a bit strange that these are sold for underfloor heating.

 

[oceansoul]

Some building management systems may well use MODBUS, it's not exclusively for PLC and SCADA. Many industrial instruments and actuators use it also. I can't see it taking off in the domestic environment. Perhaps other thermostats/controllers/actuators from the same manufacturer also have modbus and could be used to interconnect each other on a common two wire system.

 

[AdrianUK]

MODBUS is just a protocol running often (but not always) over RS485. There is also MODBUS-TCP which runs over ethernet.

The MODBUS protocol is quite old now but still very much alive. Many instruments & sensors are available with a MODBUS interface - its very easy to write a driver to pickup data using a RaspberryPi or even windows. Many open source libraries around to do this.