bamercury/activecooler

Program that configures MCU's timer registers to sample sensor data and output PWM to an HVAC cooling fan

ActiveCooler

Program that configures MCU's timer registers to sample sensor data and output PWM to an HVAC cooling fan

Hardware

Device: SparkFun Pro Micro 5V/16MHz (Atmega32U4)

Temperature Sensor: DS18B20

Fan: SanAce 92W XF-P05801, DC 24V/1.0A

• https://www.mouser.com/datasheet/2/471/San_Ace_92WL38_E-1316567.pdf

Voltage Regulator: TRACO THD 12-4812WI, DC 18-75V In, 12V/1000ma Out

• https://www.mouser.com/ProductDetail/TRACO-Power/THD-12-4812WI?qs=ckJk83FOD0X7VPMTWOOrrA%3D%3D

Libraries used:

https://github.com/milesburton/Arduino-Temperature-Control-Library

https://github.com/PaulStoffregen/OneWire

Notes

1. Make sure your Arduino IDE is setup for uploading code to the SparkFun Pro Micro Board:

   • https://learn.sparkfun.com/tutorials/pro-micro--fio-v3-hookup-guide/all

   • https://cdn.sparkfun.com/datasheets/Dev/Arduino/Boards/ProMicro16MHzv1.pdf

2. The code simply uses the linear mapping function map() to map temperatures to motor speeds

   • Motor speeds range from 0-100% duty cycle (0-100)

   • Exposed parameters are defined at the top of the code

     • MOTOR_MIN, MOTOR_MAX

     • TEMP_MIN, TEMP_MAX

3. Error Catching (In both cases, fan is turned off):

   • When sensor's sense wire is disconnected from MCU

   • When sensor itself is disconnected from ground and power

4. Exposed a parameter (SAMPLING_PERIOD) for changing sensor update rate (In miliseconds)

Wiring Schematic:

Perf-Board Assembly:

activecooler's Issues

Resources

https://linuxpropaganda.wordpress.com/2018/07/08/install-fritzing-in-xubuntu-18-04/

Spec out voltage regulator

Links to various regulators