Re: dumping a lot of heat

On Wed, 4 Dec 2024 18:53:31 -0500 (EST), Martin Rid
<martin_riddle@verison.net> wrote:

john larkin <jl@glen--canyon.com> Wrote in message:r

I'm thinking about building a biggish rackmount dummy load box. Itwould simulate series resistance and inductance. Part of the problemis that it will need to dump a lot of heat.We are using copper CPU coolers on PC boards, which are great up to acouple of hundred watts, but I'd like to do a kilowatt or two.https://highlandtechnology.com/Product/P945It would take a heap of expensive extruded heat sinks and fans to getrid of a kilowatt. At 1 K/W, a pretty good heat sink, that's 1000 degCtemp rise.A small hair dryer can dump a kilowatt. So some sort of red-hotnichrome coils and a vicious fan might work.I'd prefer to not use water.I wonder if there is some sort of runs-red-hot power resistor.

>
There are those Edison base ceramic heaters . Maybe you can cobble
up something with those.
>
Cheers

Good idea.

I recall the old screw-base ceramic cones, used in reflector-type
space heaters.

Maybe we could use the heaters that people use in ceramic firing
kilns. I know that some people make their own kilns from fire bricks
and some sort of heater bars.

Yikes, this is 5400 watts!

https://www.amazon.com/Beaquicy-Heating-Assembly-Thermostat-Resettable/dp/B083QFPSSC/

or this

https://www.amazon.com/PayandPack-Durablow-Fireplace-Replacement-compatible/dp/B00B8NY03G/


About 0.2% of the price of buying "electronic" resistors.

https://www.digikey.com/en/products/detail/vishay-sfernice/RWST40370CN1600JN/10729041