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.
Arduino pwm fan controller.
The arduino throttles the fans using pid logic and drives them through pwm.
Pwm fan controller sketch can be downloaded here.
The pc communicates with the arduino via the serial port.
4 wired fan control pwm control a pwm fan with arduino.
On the pcb there is a 5 12v input for the fan supply.
I simply want to control a 4 wired fan or maybe several with an arduino board.
For this reason i used arduinos d6 pin pwm.
Control the speed of the fan.
It then becomes a matter of telling the fan pwm to raise or lower the speed based on the temperature.
How to connect it.
Many projects that use a temp sensor but never the most simple thing.
The ultimate project is to control the fan based on temperature.
So after that no electricity flows through it turning the fan off.
Getting temperature values from a digital or analog temperature sensor on an arduino is fairly simple.
The system uses a temperature sensor to control four fans that are driven by an arduino 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.
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.
It is efficient because the pass transistor is used as a switch.
Temperature based fan speed control monitoring with arduino.
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.
There is some information out there.
Beginner full instructions provided 24 154.
I had 5 laying around and thought mine as well give it a shot.
The blue led seen on the prototype board is just for verifying correct circuit.
The temperature and fan speed are reported through a 8 digit 7 segment display fitted on a rack mounted aluminium bar.
Design schematic diagram is shown next.
A low frequency pulse width modulation pwm signal whose duty cycle is varied to adjust the fan s speed is used.
The pwm controller accepts the control signal and adjusts the duty cycle of the pwm signal according to the requirements.
Firstly make sure that you fan s are pwm controller you can check this by making sure that your fan connector has 4 wires.