Hi all;
I've got 2 PC fans (12V dc running from a 500mA rated supply). Thing is, whenever I try to use a pot to control their speed, the pot starts smoking.
This has just got to be possible, but everything I try just smokes the pot.
How can I control the fans with a 1/4 watt pot? do I use a transistor and use the tranny to control the base current, thereby avoiding the power dissipation issues?
Thanks
-Markus
really?
You're using the wrong method to control the pot.
Use a pulse width modulation system. Jaycar sell a DC motor speed control kit for about $24. It's an overkill (designed for motors up to 10A), but it will do the job. The kit number is KC-5225. Or you could use a 555 timer as a PWM, driving a transistor or a FET.
OR
Use a 3 position switch that switches the following to the fan.
"Markus Stone"
** Use an LM317 adjustable regulator IC to vary the voltage............ Phil
I found this very helpful..
smoking.
pot.
I can email you a simple circuit if you like Mel
and
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