Introduction: HomeMade SlowCooker

For a long time now I have wanted to own a SlowCooker. Unfortunately, I couldn’t decide on which one I should get. I like the expensive ones where you can set the temperature digital but, being Dutch, there is no way I'm spending that kind of money!

Now I have a little more time on my hands due to the COVID-19 crisis, I decided instead to just make one myself. I had this ceramic hot plate lying around which I was already using for my pot roasts. And after diving into my parts collection, I dicovered all I needed to buy was a 4 euro temperature sensor!

It is great for making stews and pot roasts, or tempering chocolate au bain marie!


  • Arduino Uno With Screw Terminal (Or any other type you have laying around)
  • DS18B20 TO-92 Thermometer - Waterproof with 1m cord
  • One 4,7KΩ resistor
  • I2C LCD Screen (I used a 16x2)
  • Small DC Power Supply (I used a Self Electronics SLT3-350IS-1 LED-driver)
  • 5V Relay Module
  • Two-Way Momentary Switch
  • Power Socket with switch + Cable
  • Heating Element / (Ceramic) Hot Plate
  • Some PCB Board
  • Some form of housing for your SlowCooker

Step 1: Hooking Everything Up

If you have acquired all of your components, it is time to connect it all together. If you like you can set everything up on a breadboard first, or go straight forward to building up your SlowCooker. In any case, I’ve included a Fritzing diagram to explain how to connect all the parts. This is my first try at Fritzing, so I apologize if it’s not entirely clear…

In real life I connected my 12V power supply directly to the power socket with switch, so that everything can run off of 1 plug. I use the switch to turn off the device when it’s not in use.

Furthermore, I’ve soldered the resistor and the thermometer to a small piece of PCB board.

If you have got everything connected correctly upload the code to your
Arduino using the Arduino IDE.

n.b. In the pictures you can see I started out with an Arduino Nano but I forgot to unplug it while I was soldering, so I accidentally fried that one... Oh well...

Step 2: Housing

Finally, you need some form of housing for all your parts. I chose to make a cube (120x120x120mm) out of 9mm multiplex with holes for the various external components. I have to admit: it’s not my best work, it's a little tight, but it does the trick.

A plastic container might also do well as a housing, but that’s up to you!

After you've put everything in your housing it's time to start cooking!

Good luck and have fun!