Arduino Pwm Fan Controller

The pc communicates with the arduino via the serial port.

Arduino pwm fan controller.

It is efficient because the pass transistor is used as a switch. On the pcb there is a 5 12v input for the fan supply. Temperature based fan speed control monitoring with arduino. I o pin 9 on the arduino board is directly connected to fan control input and by reading the state of 3 push buttons on pins 2 3 4 different pwm values are sent to the fan.

In the above wave forms you can see that the frequency is same but on time and off time are different two applications of pwm control using arduino is shown here. Design schematic diagram is shown next. The ultimate project is to control the fan based on temperature. Many projects that use a temp sensor but never the most simple thing.

The arduino throttles the fans using pid logic and drives them through pwm. An inexpensive single small pass transistor like 2n222 or bd139 can be used here. The temperature and fan speed are reported through a 8 digit 7 segment display fitted on a rack mounted aluminium bar. Getting temperature values from a digital or analog temperature sensor on an arduino is fairly simple.

It then becomes a matter of telling the fan pwm to raise or lower the speed based on the temperature. I simply want to control a 4 wired fan or maybe several with an arduino board. The system uses a temperature sensor to control four fans that are driven by an arduino controller. Control the speed of the fan.

For this reason i used arduinos d6 pin pwm. A low frequency pulse width modulation pwm signal whose duty cycle is varied to adjust the fan s speed is used. Pwm fan controller sketch can be downloaded here. Pwm waves with various duty cycle are shown in the figure below.

There is some information out there. The system works by an application running on the pc checking the cpu temperature and checking whether to speed up or slow down the fans. So after that no electricity flows through it turning the fan off. 4 wired fan control pwm control a pwm fan with arduino.

I had 5 laying around and thought mine as well give it a shot. How to connect it. Firstly make sure that you fan s are pwm controller you can check this by making sure that your fan connector has 4 wires. Beginner full instructions provided 24 154.

I have been wondering about this project and how to control my 4 pin pwm fans. The frequency values can be adjusted between 125 hz 8 mhz as well as a variable duty cycle. As long as the cooling is on the red led is on when not cooling the green led is on.