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Electrical Dummy current question
Old 25th January 2020
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Electrical Dummy current question

Ok, incorporating a new piece of gear into my 10A breaker home 120v circuit. This new piece of gear consumes 1A from its 5.7V power supply. I am wary of overloading my home 10A circuit and first need to know how much current this new piece of gear is actually going to draw from it. Basic electrical question I know but still would like to verify before the new gear is delivered and I risk blowing my breaker just plugging it in.
Old 25th January 2020
Lives for gear
You can't know for sure, since power supply circuits (and even wall warts) differ. All you know is that its output is 5.7 V, 1 A... or ~6 watts.

But understand this: anything the power supply consumes that doesn't turn into the ~ 6 w needed by the circuit has to be turned into some other form of energy*. Usually that's heat, but it could also be sound or light. So unless the supply runs incredibly hot (or bright), I wouldn't expect it to draw much more than 100 mA from a 110v wall outlet.

If you want to know for sure, invest in a Kill A Watt or similar plug-in meter. They run about $25, and every studio and/or homeowner should have one.

* Or mass. E=mc^2. ; )
Old 10th February 2020
Here's how to do this:

1 Amp x 5.7 V = 5.7 Watts

5.7 Watts / 110 V = 0.0518 Amps

So, at the 110V level, it will draw an additional 0.05 (or 1/20 of an amp) if you exclude the power that is wasted as heat by the wall wart, which should be neglible.

I wouldn't sweat it too much, just plug it in, you'll be fine.
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