Arduino Pwm Fan Controller

4 wired fan control pwm control a pwm fan with arduino.

Arduino pwm fan controller.

There is a jumper for switching the power supply from arduino or the 12v input. An inexpensive single small pass transistor like 2n222 or bd139 can be used here. Pwm fan controller sketch can be downloaded here. The temperature and fan speed are reported through a 8 digit 7 segment display fitted on a rack mounted aluminium bar.

How to connect it. For this reason i used arduinos d6 pin pwm. The system uses a temperature sensor to control four fans that are driven by an arduino controller. Many projects that use a temp sensor but never the most simple thing.

It then becomes a matter of telling the fan pwm to raise or lower the speed based on the temperature. On the pcb there is a 5 12v input for the fan supply. A low frequency pulse width modulation pwm signal whose duty cycle is varied to adjust the fan s speed is used. The arduino throttles the fans using pid logic and drives them through pwm.

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. The blue led seen on the prototype board is just for verifying correct circuit. Getting temperature values from a digital or analog temperature sensor on an arduino is fairly simple. Firstly make sure that you fan s are pwm controller you can check this by making sure that your fan connector has 4 wires.

Control the speed of the fan. The pwm controller accepts the control signal and adjusts the duty cycle of the pwm signal according to the requirements. I had 5 laying around and thought mine as well give it a shot. I have been wondering about this project and how to control my 4 pin pwm fans.

There is some information out there. I simply want to control a 4 wired fan or maybe several with an arduino board. So after that no electricity flows through it turning the fan off. Beginner full instructions provided 24 154.

The frequency values can be adjusted between 125 hz 8 mhz as well as a variable duty cycle. 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. The pc communicates with the arduino via the serial port. 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.

It is efficient because the pass transistor is used as a switch. Temperature based fan speed control monitoring with arduino. Pwm waves with various duty cycle are shown in the figure below.