1.8 KiB
Resources/mathematics/Proportional Integral Derivative Controller for the Gaggia Baby Millenium
Parts Used
First Day
The first day was on Friday the 27.05.2023. I went with Kilian to the house he grew up in because he had to do some measurements for his Bachelor Thesis.
In a few hours i first checked if i could connect the relais i bought, which is this one:
This was my first mistake, because I did not check the input voltage and only thought about how much current it could handle. The specific SSR i bought is driven by a current of 80~250 Volts AC, which the ESP32 can’t output. I had noticed this a few days earlier and went to a local electronics store and bought a classic mechanical relais. This was the second mistake I did 😀
The thing is normally you would use this sort of relais with a small circuit (octocoupler) that isolates the relais’ control circuit from the ESP32. These circuits look like this:
Gladly i had a grove devkit with me, so atleast i got to try out connecting one of those relais to the esp which was very easy.
Then I also tried to connect my MAX6675 Thermocoupler to the ESP32. This was very easy to do as I found a schematic online. The MAX6675 uses Resources/mechanics/SPI.