ESP8266 Community Forum

- Wed Nov 01, 2017 4:39 am #71434 For the temp sensor if you are ok with soldering then you can put them together very cheaply using components directly rather than all those break out boards.

https://www.thingiverse.com/thing:2166068 shows a box I use to package my temp sensors in. I use a mix of usb powered and mains powered units.

For the mains powered I use
ESP-12F
DSB18B20 sensor (to-92)
HLK-PM03 AC mains 3.3V power module
wire fuse for protection
3 resistors plus decoupling capacitor
Total cost < UKP 4

Note that I remotely mount ds18b20. Locally mounted will normally mean it gets heated above ambient. I find if it is on a short stub of > 3cm then you get good results.

- Wed Nov 01, 2017 12:51 pm #71447

Are those boards the most pricy option for me instead of the ESP01S?

Wemos D1 Minis (or clones) cost less than 3$ and since they have a regulator on board, you don't need the AMS1117 board from your list, so it's actually cheaper than the components you posted.

Then I also want to build 20-40 230v relays too based on the ESP8266 - but that's another thread :D

I'm with philbowles on this one: don't mess with mains voltage, buy something that works and is safe.