Element amperage question

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CJBrewVT

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My understanding is that AC fluctuates and can vary slightly. If a 2000 watt heater for 120 volts pulls 16.6 amps, does it pull more amps to maintain watts if the voltage drops to say 110 volts?

Do some of you run 2000w on a 20 amp circuit? It's close to the 80% threshold.
 
No. Elements are fixed resistance, so if you drop the voltage the current will drop as well.

Use I = V/R to find the current at any voltage (I = Amps, V = the RMS voltage, or say 110).

For your element, the fixed resistance of the element, R, is 7.2 ohms. (R = V^2/W = 120^2 / 2000 = 7.2)

So, @ 110V, the current is I = V/R = 110/7.2 = 15.3A
 
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