• uneatable@lemmy.world
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    1 day ago

    Ok. I was acountless on lemmy for a long time, your comment made me finally register. Thanks!

    So, yeah, with double the voltage you get 4x the power. But you you put 4 times the power at 50% of the time, you get only 2x the power. And the other half of the time, you get 0 power. On the average you get the same power output.

    • ch00f@lemmy.world
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      1 day ago

      You double counted there.

      You said 4x power 50% of the time and then said “the other half of the time.”

      So you’re calculating 50% of 50% which is 25% duty cycle.

      • uneatable@lemmy.world
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        1 day ago

        Oh no, I didn’t. Should I draw a graph? Pop out some equations?

        Let’s say P is the nominal power. When I said “The other half” I meant when the solder iron is not plugged. So:

        50% of the time at 4xP 50% of the time at 0…

        Oh shizzzz, you’re right!

    • brucethemoose@lemmy.world
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      22 hours ago

      I had to think about it too, lol. This is an equation for DC/instantaneous power, and if you want to get into AC math, this is more like a square wave. Averaging the power out over time doesn’t necessarily work with the equation, as you figured out, as it doesn’t when you try to measure AC (sinusoidal) power by average voltage or whatever.