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If you want a good dummy load, go to the dump and pull the element out of an electric clothes dryer.
It will be a metal pan 2' in diameter with ceramic lifting plates that hold a thick coil of nichrome (like a Slinky) in a circle around the pan with two spade terminals on each end of the wire.
A clothes dryer is 240v and maxes at 7200 watts, almost all of which is the element.
That makes the element around 8 ohms (though it probably is lower when cold and higher when hot).
It's designed to have a fan blowing air over it non-stop to cool it obviously, but then it's also designed to sit in a metal box. Not sure just how hot it would get if you gave it 240v.
You could run a gater clip anywhere down the coil like a variac to tap progressively smaller sections of the total resistance, though note that you'd be heating the wire section increasingly hotter. I'd consider hooking the coil up in parallel pairs or tripples (cut and restitch the coil) if you want more heat or lower voltage.
Alternatively, an oven heating coil (3000 watts, 240v) can be pretty much flatlined without damaging it, ditto for stovetop elements (1000-3000 watts), both of which you can get for cheap/free at the dump if you're kind and polite and mention it's for a science project for school. These make great loads and you can safely sink them into a metal can of water (except for where the ends are exposed through the white insulator). They're insulated and designed to be rapidly chilled because that's what putting a cold pot of water on them does anyway.
Water has massive heat capacity, so, a simple tank will take forever to actually boil itself dry and the element can handle full power in open air without fan cooling regardless.
It will be a metal pan 2' in diameter with ceramic lifting plates that hold a thick coil of nichrome (like a Slinky) in a circle around the pan with two spade terminals on each end of the wire.
A clothes dryer is 240v and maxes at 7200 watts, almost all of which is the element.
That makes the element around 8 ohms (though it probably is lower when cold and higher when hot).
It's designed to have a fan blowing air over it non-stop to cool it obviously, but then it's also designed to sit in a metal box. Not sure just how hot it would get if you gave it 240v.
You could run a gater clip anywhere down the coil like a variac to tap progressively smaller sections of the total resistance, though note that you'd be heating the wire section increasingly hotter. I'd consider hooking the coil up in parallel pairs or tripples (cut and restitch the coil) if you want more heat or lower voltage.
Alternatively, an oven heating coil (3000 watts, 240v) can be pretty much flatlined without damaging it, ditto for stovetop elements (1000-3000 watts), both of which you can get for cheap/free at the dump if you're kind and polite and mention it's for a science project for school. These make great loads and you can safely sink them into a metal can of water (except for where the ends are exposed through the white insulator). They're insulated and designed to be rapidly chilled because that's what putting a cold pot of water on them does anyway.
Water has massive heat capacity, so, a simple tank will take forever to actually boil itself dry and the element can handle full power in open air without fan cooling regardless.
