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Potentiometer For 12volt Fan

laserpyro

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Hey Guys
Regarding My Spiro Project
What potentiometer will i need to control the fans i know my 50k is too much.
Thanks
 

HIMNL9

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Only check that your potentiometers have enough power, otherwise you risk to fry them (a 12V fan that adsorb 150 mA, usual values in PC fans, eats 1,8W, after all).

Anyway, if you want to do it a bit more professionally, use speed regulator circuits, instead just potentiometers ..... a pair of transistors and few other components, it's easy to build ..... or, being this a laser forum, you probably have already around some old LM317, and with this and one potentiometer, one resistor and two capacitors, you can assemble it in a flash ;)
 

ColdStl

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Only check that your potentiometers have enough power, otherwise you risk to fry them (a 12V fan that adsorb 150 mA, usual values in PC fans, eats 1,8W, after all).

Anyway, if you want to do it a bit more professionally, use speed regulator circuits, instead just potentiometers ..... a pair of transistors and few other components, it's easy to build ..... or, being this a laser forum, you probably have already around some old LM317, and with this and one potentiometer, one resistor and two capacitors, you can assemble it in a flash ;)
what values for the pot, resistor and capacitors do you recommend?
 

HIMNL9

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If you need it just as speed regulator, you can use a lot of values, cause there's nothing critical in the circuit, used in this way (i mean, not as current regulator like for the LD's)

A circuit similar to this, can work without any problem for the most part of the PC fans, and is realizable also wih spare or "used" parts you find around, if you need it on-the-fly :) (for definitive use, i anyway suggest to put the regulator on somethng that act as heatsink)



The 100 nanofarad cap on the adj pin can also be omitted, it just keep it more stable :)
 

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HIMNL9

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^ These ones works cause are WIRE potentiometers, not carbon layer ones :)

Most of the times, peoples uses normal carbon layer potentiometers, and fry them (your model is almost 10 times robust than a carbon layer one :)

I was thinking you referred to carbon layer ones, for this reason suggested a regulator :p
 

ColdStl

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^^ thanks. I think I actually understand your diagram :yh:
I'm gonna give it a try.
 




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