Network of devices for Beginners

In my part of town, Raspberry Pi devices and their work-a-likes are inexpensive and widely available.

I have OpenHABian running on a Pi3 and a Pi Zero W that I want to use for I/O.

I think using this setup for MODBUS TCP and MQTT experiments would be great.

I have a DS18B20 thermocouple to try on the 1-wire and a fan connected to a MOSFET on a tiny PCB.

Has someone done this already? Any pointers?

Thank you,

  • dan

On my gas stove, Im using a thermocouple connected to an esp8266-01. I read the voltage output of the thermocouple and pass that data to openHAB. When voltage gets near 300 millivolts, then I know the gas stove is lit (on). When I arm the house, and openHAB detects gas is ON, it sends me a text message to my phone. Same rule apply for my human presence logic. If openHAB determines no one is home and thermocouple is hot (i.e., 300+ millivolts) then it sends me a text message as well.

Im also using a simple thermocouple. Just go to eBay and search for a furnace or water heater thermocouple. They are industry standard for such applications. These things turn on/off the gas valves in most water heater/furnace applications.

eBay stuff:

A mosfet can work but I have no idea what you are trying to achieve…

…the Pi0w can read the temp and send that to OH on my Pi3.

If the temp gets too high, the Pi3 can send a message and have the Pi0w turn on the fan! I have pretty good WiFi coverage, so could have many remote Pi0w.

Makes a simple demo to try out OH, Raspian, MODBUS and MQTT, I would think…

I mostly want to play with the networking and protocols.

Thank you!

Temperature of what? If you just want to have something on/off based on temp remotely, I would suggest an ESP8266 rather than a piZeroW. An esp8266 can be had for $2