esptemp8c

Open source, 8-channel temperature logger using esphome for Dallas DS18B20 sensors.

What's in the box

• Fully assembled circuit board

Sensors

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.

In theory, this unit can handle more then 8 sensors if you start piggy-backing the terminals for multiple sensors.

Powering

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, and you might get away with up to 30VAC. - 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.

Flashing

You can use any ESP32 programmer and connect the proper pins to the programming header next to the ESP32. The programmer will need to trigger GPIO0/EN pins accordingly, or you will need to wire up your own buttons to do so. The programming pinout matches the eflashy32 ESP32 programmer.

Enclosure

Fits in a Hammond 1593VBK. Or you can make your own enclosure and 3D-print it (contributions welcome).