I just finished new revision of my old project — the multi-purpose controller for incubator.
This open source and open hardware project with all material in GitHub:
The hardware is available to purchase at my Tindie store: https://www.tindie.com/products/akpc806a/incubator-controller-with-bluetooth-and-android-ap/
- Temperature regulation using one of three methods: on/off control, proportional-integral (PI) control by heater power variation and hybrid control (combination of on/off control and PI).
- The heater is driven by a phase-controlled dimmer.
- Automatic PI controller tuning implemented in an Android application.
- Humidity regulation using simple on/off control.
- Timer for automatic rotation of eggs.
- Buzzer controlled by configurable protection limits for temperature and humidity.
- Three configurable 120V TRIAC outputs, which are galvanically isolated from control side.
- Modbus protocol over Bluetooth.
- Commutated AC mains: 120V 60Hz
- Output power per channel: 100W (300W tested with heatsink)
- Temperature range: 5 °C … 60 °C (based on specified accuracy)
- Humidity range: 20 % … 80 % (based on specified accuracy)
- Temperature resolution: 0.01 °C
- Temperature accuracy: ± 0.3 °C
- Humidity resolution: 0.04 %
- Humidity accuracy: ± 2 %
- Control power supply voltage: 5V…20V 60mA
- PCB size: 40 mm x 56.5 mm (1.57 x 2.22 inch)
- Temperature sensor: HTU21D
- Microcontroller: STM32F030K6T6
- TRIAC: BTA08-600CWRG
- Bluetooth module: HC-05
Here is the picture of assembled PCB