Need help with a resistor

[midnightrat]

It's the resistor from the Zalman quiet fan. I believe it lowers the 12v line to 7volts. Anyone know where I can pick up some more?

pic of resistor

midnightrat

 

[GalvanizedYankee]

With your DMM the resistance could be tested. The resistance requiored for a given voltage drop is determined buy the wattage of the draw.

Thank jonnyguru.com for this link http://www.sengpielaudio.com/calculator-ohmslaw.htm


...Galvanized

 

[Geomagick]

You want a 56 ohm resistor with a 5% tolerance as a replacement.


This is a useful tool

 

[imported_rod]

That image is backwards. But the colours appear to be: Green-Blue-Black-Gold. If so, that would mean it's a 56 Ohm resistor, with +/-5% tolerance. Probably a 1W-3W one. You should be able to buy a 3Watt 56Ohm resistor from an electronics store for about $0.20.

RoD

P.S. It doesn't necessarily drop it to 7V, but it does drop the voltage. If you want a better solution, maybe look for a fron panel solution, like my one: http://www.pccasegear.com.au/prod850.htm. It gives you control and uses PWM technology so you can turn the fan down even lower than with a resistor.

EDIT:

Originally posted by: George Powell
This is a useful tool

Tool. Bah. EE's have that stuff memorised.

 

[midnightrat]

Thanks guys, exactly what i needed.

Unfortunately I don't have the space for the fan controller and was just looking for something that i could just solder onto some wires.

I took the resister to Radioshack since I figured they would know, man where they useless.

 

[Madwand1]

A Zalman Fanmate would be a natural step-up replacement; a multi-fan controller if you're doing many of these in the same box.

(Perhaps a set of zener diodes if you're feeling adventurous.)

 

[Geomagick]

Originally posted by: Madwand1
A Zalman Fanmate would be a natural step-up replacement; a multi-fan controller if you're doing many of these in the same box.

(Perhaps a set of zener diodes if you're feeling adventurous.)

Why would you want a zener diode in a fan circuit?

 

[Madwand1]

Originally posted by: George Powell
Why would you want a zener diode in a fan circuit?

For a more consistent voltage drop amond different fan types as compared to a single resistor. However a variable device will let you tune this better.

 

[GalvanizedYankee]

Originally posted by: George Powell

Originally posted by: Madwand1
A Zalman Fanmate would be a natural step-up replacement; a multi-fan controller if you're doing many of these in the same box.

(Perhaps a set of zener diodes if you're feeling adventurous.)

Why would you want a zener diode in a fan circuit?

Well mad King George with the 777. Here is a Brit site that will explain the whys and hows for the dedicated DIYer. The rest of the site is worth the look=old but good info.

http://www.cpemma.co.uk/diodes.html


...Galvanized

 

[JimPhelpsMI]

Hi George, A zenner diode in series with a DC device and polarized in the right direction will drop the voltage the amount the diode is rated at. Not a good thing, but it does work. Jim

 

[midnightrat]

ok, you guys are getting way to technical for me...i'll just try the resister first, then if i get adventurous i'll ask about the diode thingamabob.

rat