Emergency 12V fan/light

Thread Starter

john.snow

Joined Dec 17, 2015
3
Hello everyone,

I have been working on an emergency 12v fan and light system for camping. However, I keep getting stuck with burnt resistors and POTs when trying to control the fan's speed. Moreover, I wanted to to take a different approach by using PWM (555 timer) circuit, but I really have no idea how to use it. The fan I am using is a 12vdc car (lighter plug) fan which draws current of 2.5 amps. I've read that you can achieve high frequency pwm using this circuit. Another question, Is it possible to build a circuit that will control the fan at very low speed with least motor kick.

Pardon me for my lack of understanding.
 

dl324

Joined Mar 30, 2015
10,003
Your first post... Welcome to AAC!

Post a schematic and someone might be able to help you make it work. Sounds like you could be using your pot as a rheostat and exceeding it's power rating.
 

Sensacell

Joined Jun 19, 2012
2,564
And beware that some brushless type DC fans do not like PWM.

It can crash the electronic commutator chip in the fan.

Some have actual PWM inputs...
 

RRITESH KAKKAR

Joined Jun 29, 2010
2,829
Hello everyone,

I have been working on an emergency 12v fan and light system for camping. However, I keep getting stuck with burnt resistors and POTs when trying to control the fan's speed. Moreover, I wanted to to take a different approach by using PWM (555 timer) circuit, but I really have no idea how to use it. The fan I am using is a 12vdc car (lighter plug) fan which draws current of 2.5 amps. I've read that you can achieve high frequency pwm using this circuit. Another question, Is it possible to build a circuit that will control the fan at very low speed with least motor kick.
Hello,
I have done this with pic micro 16f676 & 877A and H-Brigdes
do you nee code?
 
Top