Cooler running resistor

[Sylvester]

Not sure of the power draw on a circuit, the resisor specified is a 56 ohm 5 watt, what can I use that is cooler running? The resistor is used as a load on a 12v circuit.

[rievax_60]

Re: Cooler running resistor

A physically larger resistor like a 10 watt resistor will have less temperature rise because of its lager surface area. Or you could attach the 5 watt resistor to a finned heatsink.
Or use a high resistance if it doesn't cause other problems.

[R_J]

Re: Cooler running resistor

56 ohms accross 12 volts is about 214 ma of current, so the wattage would be about 2.6 watts.

[Sylvester]

Re: Cooler running resistor

Thanks, probably go for a 10w resistor, did think of an aluminium ohmite resistor, think they do a 15w one.

[petehall347]

Re: Cooler running resistor

any wattage resistor will get as hot . use a heat sink to dissipate the heat or install a fan

[Sylvester]

Re: Cooler running resistor

Fan not practical, I'll use a heatsink.

[PeteS in CA]

Re: Cooler running resistor

Thanks, probably go for a 10w resistor, did think of an aluminium ohmite resistor, think they do a 15w one.

Keep in mind that those finned panel mount resistors are designed to have some sort of heat (like a ........ panel). Without that a 15W resistor might be 5-7 watts or something like that.

[R_J]

Re: Cooler running resistor

What are you doing? Is this 56 ohm resistor just there to put some load on the 12 volt power supply?