Hello,
I have a 4 wires Fan from my old Macintosh. I tested it with 9V batterie and with 5V Arduino supplier and the Fan seems to work pretty well. But i saw in a lot of documents that the operation votage of a fan shall be 12V.
So my question: Is it ok to supply a Fan with 5V or 9V? Is there any side effects?
Thank you!
From my understanding, providing 5V to the fan will make it consume way more current.
You could use a MOSFET to control the fan from another device that doesn't work at 12V.
Be aware the Arduino boards have current limits.
Look up any label or number or see if it has voltage written on it .
Don’t run it from the Arduino 5V supply
(4-pin) PC fans are designed for 12volt, but should be ok with 9volt (not a whimpy 9volt smoke alarm battery).
I doubt they can be reliably powered (the fan part) with 5volt.
Most PC fans draw <300mA, but startup and speed might be a problem on 5volt.
And powering motors from Arduino's supply is generally a bad idea.
Two pins are for power/ground. Two pins are for speed control (PWM) and tach (RPM feedback).
Those PMW/tach pins expect to see 5volt logic.
Plenty of examples on the web.
Leo..