Beer Baker

Beer brewing temperature control.

BOM

• Waveshare ESP32-S3-LCD-1.28
• Shelly Plug S
• DS18B20 temperature sensor
• 4.7k resistor (between VCC and Data connectors of DS18B20)
• Terrarium heat mat
• Powerbank (for the ESP32, optional, otherwise simple USB)

Operation

CLI

# Setup the config with a temperature sample bias:
$ config-set -name "ds-offset" -value "-2"
$ config-save
16:24:16.877 -> saving config ... 124 bytes written
$ restart

# Print the config, then sample temperature:
$ config
Config
------
auto-start = 0
wifi-ssid = ShellyPlusPlugS-D4D4DAED3310
wifi-pass = BeerHeater
plug-ip = 
plug-auto-off = 0
ds-offset = -2.000000
$ sample
Scan OW Bus:
  Device count: 1
  DS18 count: 1
Request temperatures ... OK.
 
Sample
------
ds18b20:
  temperature C = 20.375000 (sensor value: 22.375000)

$ sample
Sample
------
ds18b20:
  temperature C = 20.312500 (sensor value: 22.312500)

# Plug ON
$ on

# Plug OFF
$ off

Hardware Notes

Waveshare ESP32-S3-LCD

Configure Arduino IDE/Project

Board: ESP32S3 Dev Module Port: USB 6 (or similar)

Shelly Plug S

Configuration

Adjust settings from default:

Setting	Value
WiFi Mode	Access Point (AP) Mode
WiFi Network SSID	(SSID is predefined and cannot be configured)
WiFi Network Password	BeerHeater (or your choice)
IP Address	192.168.33.1 (default, change if required)
Timer / Auto Off	Enable, starting value 1800 (*)

(*) The Auto Off timer will protect the beer from overheating in the case that the temperature controller fails. Adjust according to your individual setup.

Factory reset: Plug/power device and then hold control button for 10 seconds (and within 1 minute of powering the device).

DS18B20

1-Wire Interface:

Vcc (red) o----------o------o H1 Pin 18 (VCC)
                    .|_
                    |  |
                    |  | 4.7k
                    |__|
                     |
Data (yellow) o------o------o H1 Pin 19 (GP 14)
Gnd (black) o---------------o H1 Pin 20 (GND)

Design

Feature Set

1. CLI (USB Serial) for configuration.
2. Persist configuration between restarts.
3. Programable temperature sequence.
4. Predictive control algorithm.
5. Low power mode (off between samples).
6. Over-temperature protection; regular control of PlugS, Auto Off configuration.
7. Connection to Tilt 2 SG monitor (bluetooth).
8. Visualization via screen/dial (on/off/temp/target), touch to wake.
9. Touch screen interactions (on/off/stop)
10. Notification and alerts (Bluesky via WiFi/Bluetooth gateway).

Links and References

• ESP32-S3-LCD-1.28
  • Onboard Interface
  • ESP32-S3 Datasheet
• Arduino Libraries:
  • Dallas Temperature Control Library
  • Arduino Json
  • WiFi Client
  • HTTP Client
  • Simple CLI