The temperature and fan speed are reported through a 8 digit 7 segment display fitted on a rack mounted aluminium bar.
Arduino pwm fan controller.
4 wired fan control pwm control a pwm fan with arduino.
The frequency values can be adjusted between 125 hz 8 mhz as well as a variable duty cycle.
It is efficient because the pass transistor is used as a switch.
I have been wondering about this project and how to control my 4 pin pwm fans.
Pwm fan controller sketch can be downloaded here.
The blue led seen on the prototype board is just for verifying correct circuit.
The arduino throttles the fans using pid logic and drives them through pwm.
The system uses a temperature sensor to control four fans that are driven by an arduino controller.
Control the speed of the fan.
Design schematic diagram is shown next.
Beginner full instructions provided 24 154.
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.
The pc communicates with the arduino via the serial port.
How to connect it.
There is some information out there.
For this reason i used arduinos d6 pin pwm.
There is a jumper for switching the power supply from arduino or the 12v input.
Pwm waves with various duty cycle are shown in the figure below.
Many projects that use a temp sensor but never the most simple thing.
An inexpensive single small pass transistor like 2n222 or bd139 can be used here.
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.
Getting temperature values from a digital or analog temperature sensor on an arduino is fairly simple.
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.
So after that no electricity flows through it turning the fan off.
I simply want to control a 4 wired fan or maybe several with an arduino board.
The ultimate project is to control the fan based on temperature.
Firstly make sure that you fan s are pwm controller you can check this by making sure that your fan connector has 4 wires.
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.
As long as the cooling is on the red led is on when not cooling the green led is on.
