Running a fan controller from a dc adapter

[Olaw]

Hi, i have a pc inside my livingroom ikea cabinet, which i have modded to have air flowing past the walls. I need intake/exhaust fans running at different speeds from my Akasa fan controller, which is soldered to  a basic 12v 1A dc wall adapter. Is it okay to regulate it from the fan controller with fans running at different voltages? (different spec fans) I measured the power consumption one day and it's drawing about 1-2 watts, yet the adapter gets quite warm during the day.

[OhioYJ]

Oversizing the adapter will keep it cooler. However it being warm might not necessarily be an issue. Most adapters will get a little warm during use. I will say I'm using a 12V, 4 amp adapter for my fans on my rack and it does stay pretty cool (obviously, I'm nowhere near 4 amps). 

 

As for controlling the fans with voltage, yes you can do that, however that's just dumping the heat somewhere else with another device. Your 12v adapter will still be seeing 12 volts of load too, unless I'm misunderstanding what your plan is there. 

[OhYou_]

Are you using different spec fans as in one is 5v and one is 12v or something?
Because some fan controllers do not even go low enough to 5v, if they are even the type that controls voltage opposed to pwm.
Beyond that, there is no issue with using a dc adaptor of suitable spec to power a fan controller. If the controller is a variable voltage type, it will get warm by design.

 

The output of heat is proportional to the voltage difference, aka slower fan = more heat because the design usually doesn't mean it simply uses less power to spin slower. It overall consumes the same power but the controller vents some, leaving less for the fan, so it spins slower.