Arduino + Blynk basics and code

[shoo]

Just wanted to put this here in case anyone else is looking for a head start on a home coded arduino-based brewery with control through Blynk, with a basic parts list and some barebones intro code for PID-based temperature control.

Also, general shoutout to @BrunDog (developer of the much better arduino-based BruControl) for putting me on to Blynk

A few notes:

• This is recommended only for those with previous coding and electronics work, as it's a bit complicated.
• The code posted has a lot stripped from it for simplicity. I am not sure it works, because I haven't actually tested this version. Happy to correct errors if people find them. That being said...
• I am happy to help, but I won't be spending a lot of time doing tech support here (I don't spend much time on HBT). This is just to give others a jumping off point.
• I am not responsible if you use any of this information and something goes wrong, for any reason whatsoever.
• Blynk is great, but if you are trying to do a lot of actual automation with it, you'll probably have to break some of the Blynk standard/best practices. Also note that Blynk eats processor time, which can be a serious problem with the, erm, diminutive arduino processors.
• The autotune algorithm and settings could definitely use some work, and I am not happy with the #s it produces. You are probably better off doing some educated guess and check. To start with, my values are Kp: 900, Ki: 500, and Kd: 100.
• Setup is very complicated and tricky, and I am not providing a tutorial here.

Major control panel parts specific to a simplified version of my arduino build

• Arduino (I am using an arduino mega clone, but if you don't need the pins you could use an uno)
  • Consider using an ESP32-based board to take advantage of the massively faster processor and the built-in wifi. Definitely less beginner-friendly and hackier.
• 12v power supply for arduino (1a or higher preferably)
• 5v power supply to power relay board and ESP-8266 wifi module (just using the arduino built-in supply probably won't cut it)
• 5v relay(s) (I use a relay board)
• SSR w/ heat sink
• RTD / PT100
• RTD amplifier board (note that the setup is complicated and tricky, see here)
• ESP-01 (note: getting this to work is definitely the hardest part of the whole project, I recommend watching this)
• Lots of wiring and jumpers and terminals, depending on how you want to wire it all up

Blynk project QR code:

Code for Blynk / Arduino project attached as arduino_blynk_lite.txt