bangbang-kegerator

Simple temperature control module

parts

some of these are cheaper from places other than amazon.

• Thermometer and resistor https://www.adafruit.com/product/381
• Power relay (plug whatever cooling or heating element into this) - https://www.amazon.com/dp/B0178IC734
• Raspberry Pi Zero W and power- https://www.amazon.com/dp/B071L2ZQZX

attach the thermometer

this tutorial might help - just soldier things to the correct leads

https://learn.adafruit.com/adafruits-raspberry-pi-lesson-11-ds18b20-temperature-sensing/hardware

Set up the monitor

• go to drive.google.com
• add google scripts

• make a script with the following code and save it

function doPost(e) {
  props = PropertiesService.getScriptProperties();
  arr = JSON.parse(props.getProperty("last_n") || '[]');
  arr = arr.slice(0, 100);
  arr.unshift(new Date() + " - " + e.postData.contents);
  props.setProperty("last_n", JSON.stringify(arr));
}

function doGet(e) { 
  props = PropertiesService.getScriptProperties()
  arr = JSON.parse(props.getProperty("last_n") || '[]');
  return HtmlService.createHtmlOutput("<pre>" + JSON.stringify(arr, null, "  ") + "</pre>")
}

• go to publish > deploy as web app
• save the link (you need to replace my link in index.js

setup

• install raspbian - https://www.raspberrypi.org/downloads/
• install nodejs on the computer apt-get install node
• install the dependencies of this package. npm install
• fix the URL in index.js
• set up a minutely cron - https://www.raspberrypi.org/documentation/linux/usage/cron.md