What should I use to adjust an electric fans speed?

[cat007]

I tested the inverter last night - running 2x500watt halogen lights for an hour the inverter wasn't even warm. In fact it was still cold to the touch.
The fans run full tit ALL the time and are loud as hell so I'm wanting to be able to turn them down a bit. Of course I'll do some testing first to make sure it doesn't get hot etc - but I'm wondering what sort of variable resister I could use?

Assuming the fan’s run off the 12v side of the circuit I was thinking something like this: http://www.jaycar.co.nz/productView.asp?ID=RP3975&CATID=33&form=CAT&SUBCATID=776 ??

Or maybe thinking of using a 3 step speed controller that I’ve already got at home from a computer’s CPU fan….

What do people think?

Cheers
Hunt

[Bazda]

Dont know if the potentiometer is the way to go.

I would be putting in a DC motor controller.

http://www.jaycar.co.nz/productView.asp ... rm=KEYWORD

[cat007]

Dont know if the potentiometer is the way to go.

I would be putting in a DC motor controller.

http://www.jaycar.co.nz/productView.asp ... rm=KEYWORD

Hmm good idea. Was hoping to not have to spend $30 on one though lol

[postfach]

What size are the fans? IMO your safest bet is to install something like a thermaltake smart case fan, it has a temperature probe on it and adjusts its speed accordingly, that way you can install it and not need to worry about fiddling with pots/dc motor controllers.

[cat007]

What size are the fans? IMO your safest bet is to install something like a thermaltake smart case fan, it has a temperature probe on it and adjusts its speed accordingly, that way you can install it and not need to worry about fiddling with pots/dc motor controllers.

Great idea. But that's probably going to be getting on the 'too expensive' side

I'm not sure what size the fans are. Small but powerful so they probably do draw a far bit of current. Although I don't think they too be on so much....

I just pulled a little fan speed controller off the back of a PSU. Doesn't look like it could handle much power going through it though....

[sergei]

It would be cheaper to get a thermal speed controller for PC fan and use that, most likely the fans you are talking about are PC ones (probably 60mm). Just make sure the controller can handle the current (it should say on the back of the fan, it is usually around 0.1-0.5A (100-500mA).)
Normal variable resistor will not cut as there is too much current going through which in turn can make it burnout.

Have a look here http://www.overclockers.co.nz/product/c ... ndex.shtml

[cat007]

It would be cheaper to get a thermal speed controller for PC fan and use that, most likely the fans you are talking about are PC ones (probably 60mm). Just make sure the controller can handle the current (it should say on the back of the fan, it is usually around 0.1-0.5A (100-500mA).)
Normal variable resistor will not cut as there is too much current going through which in turn can make it burnout.

Have a look here http://www.overclockers.co.nz/product/c ... ndex.shtml

thank you for that. I'll look into some of those options