Open source, n-channel temperature logger using esphome for Dallas DS18B20 sensors. Powered by an ESP32-C3-MINI, it can be powered by USB-C or by 24VAC.
They can be found at various locations, including DFRobot, Adafruit, Digikey or the usual suspects.
You will need to find out your sensor ID's as per the esphome documentation.
If you are using a Dallas DS18B20 sensor, I strongly recommend using Digikey, Mouser or Adafruit to avoid obtaining counterfeit sensors.
Only one power source should be used.
- USB-C Jack (5V)
- Screw terminal
- It is designed for 24VAC. 12VAC is probably the minimum required for AC. Do not exceed 24VAC.
- 9VDC will be the minimum required amount if using DC, and it has been tested up to 24VDC.
A self-resetting polyfuse is included to protect HVAC equipment if sourcing 24VAC from these units. The polyfuse does NOT apply to power from the USB-C port, as the device supplying power should have overcurrent protection per the USB standard.
You must hold down the button while plugging in the device the first time to enter programming mode. The device will then show up as a USB device on your computer. You can then use the esphome flasher to flash the device.
Subsequent flashing does not require use of the button - it can be done via USBC or OTA as well.
Fits in a Hammond 1593KBK. Or you can make your own enclosure and 3D-print it (contributions welcome).