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110V 200-250Watt dummy load Answered

As the title says I`m trying to find a best solution for a 110V 200-250Watt() inductive or resistive dummy load.
Small size 4x4", rugged , as lightweight as possible and the least emitted heat . Incandescent light bulbs are not suitable. What are my options.
Thanks guys. 

Discussions

At what voltage? What size? What frequency (range)? What impedance do you need?

And a 200W dummy load will always generate 200W of heat.

110 volts, size... we`re talking no more 4x4 inch box. Frequency and impedance does not matter. As I basically need something to mimic a 200-250W power tool.

As goon wrote: a 50Ohm resistor will do. But it will get HOT. Think about adding a fan - or think about water cooling.

But a simple resistor is not a very good simulation for another reason: It is a pure ohmic load. Power tool are a inductive load. That may or may not be important for your tests.

Yes, But you need thermal paste and a heatsink

Yep, that's the kind of resistors used. Only this one has only 100W. But you can use 4 (2 parallel strands of 2 serial ones).

Still, they will et hot and need cooling. Get the data sheet and check for operation temperature range. You'll probably have to mount them on a heat sink and cool that by a fan.

Ooops, I owe you an 'm'. As a non native English speaker I just had to look up 'goon' and have to say sorry. It was an honest typo, no offence.

Me a FIN, (that is FINLAND, the most awkward, strange, foolish, stupid, most.... ewerything, language), but still, having a possibelity to a conversation in this most to me stupid language, english. So never You mind them "englandiesh" expressions. Nice people they are. Got good service ewerytime. Ooohh... lost myself of the agenda. INSTRUCTABLES, (to write that, for a FIN is a bit of challence), is for time to be one of my ABSOLUTE favor's to follow. Them people here are kind of my "soul-mates"


Me

No worries! As typos go, that was awesome!

GEE.... P=U*I... P would be Power=Watt; U would be Volt (voltage); I=
would be current (AMPS). 2. You want to lose some of the power to
something else than to the object?? There's NO shortcut, (with a
exclution of making a AC/DC/DC/step down converter)

As said: you can not waste enegry without generating heat.
And you can not simulate a motor with a resistive load especially if the load is supposed to change...

GEE.... P=U*I... P would be Power=Watt; U would be Volt (voltage); I= would be current (AMPS). 2. You want to lose some of the power to something else than to the object?? There's NO shortcut, (with a exclution of making a AC/DC/DC/step down converter)

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gmoon

2 years ago

50 (48.4) ohms of resistance will get you to 250W @ 110V. Nichrome wire is a good choice for a resistive load.

It won't simulate an electric motor very well. Those draw more current as they do more work. I gather you don't want to use bulbs, 'cause they have lower resistance initially, until they warm up.

"`cause they have lower resistance initially, until they warm up." Yes but that`s not the only problem. Lamps are fragile and emit a lot of heat. I have tested my requirements and what I get is ........

110V 60W bulb is not enough while a 110V 500W halogen is sufficient for my application. But again lamps are fragile and they emit way too much heat for my application anyway.

Whatever you do, if your load sinks 200W, you'll get 200W in heat.

Four 1000W halogen sticks in series will be 250W and they won't get really hot.
If you get the totally round ones and not the cheap ones with the glass seal poking out, you can also mount them with heat paste into aluminum cooling blocks - while still keeping a save distance to the wiring.
In case that is still too hot use 8 sticks and do the above with 4 series sticks each in parallel.