# generator coils: max power given wire gauge

I've been messing around with some neodymium magnets and magnet wire to make a generator. I've rotated my rotor as fast as I could and noted the no-load voltage. I wondered if (at this current speed) I could define a maximum theoretical wattage based on the wire gauge.

If my generator produces Vmax on a certain gauge wire, that gauge wire has a maximum current rating before it melts, so the maximum power would be Vmax * Imax?

I know there are a lot of factors that define whether or not the generator could actually, but having a theoretical max could help set some expectations.

My question is: Is this the right way to calculate the theoretical limit? I'm not sure if the power can actually go a bit higher due to coil resistance and inductances and such, so I figured I'd ask.

• Minus the heat. – user3528438 Aug 23 '17 at 0:52

While the voltage rating is quite easy to measure or compute, the current carrying capacity is more of a 'ratings' exercise. You have to do two things, (a) keep the windings cool enough and (b) keep voltage drops due to $V=IR$ within your specification.