20 Amp Circuits

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mbrooke said:
Why does the code require 20 amp circuits when in Canada 15 amp circuits are the norm for everything?
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I have no idea about Canada, but the stuff here that's gonna get plugged into a bathroom or kitchen will a lot of times draw more than 12 amps, which is 80% of 15 amps.

Most anything with a heating element is 1500w, or 12.5 amps
 
James L said:
I have no idea about Canada, but the stuff here that's gonna get plugged into a bathroom or kitchen will a lot of times draw more than 12 amps, which is 80% of 15 amps.

Most anything with a heating element is 1500w, or 12.5 amps
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80% only applies to a continuous load. 15 amps will not trip a 15 amp breaker, ever.
 
infinity said:
1875 watt blow dryer on a 15 all circuit?
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Yes

125 volts @ 1875 watts = 15 amps or 8.3 ohms

8.3 ohms at 120 volts = 14.4 amps

And that is being highly optimistic. Any manufacturer can stick a 1000 watt heater inside a tube and label the exterior as 3,500kw.
 
mbrooke said:
80% only applies to a continuous load. 15 amps will not trip a 15 amp breaker, ever.
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Heck, sometimes 20 amps won't trip a 15 amp breaker. That's not the issue anyway, imo. The question was why 20 amp circuits, and it's because 80% of 15 amps is 12. And someone has decided 80% is enough. And 12.5 is more than 12.

And as @infinity mentioned, it's upward from there

And I know it's for continous load. And I know stuff cycles on and off. But the answer is still there.
 
James L said:
Heck, sometimes 20 amps won't trip a 15 amp breaker. That's not the issue anyway, imo. The question was why 20 amp circuits, and it's because 80% of 15 amps is 12. And someone has decided 80% is enough. And 12.5 is more than 12.

And as @infinity mentioned, it's upward from there

And I know it's for continous load. And I know stuff cycles on and off. But the answer is still there.
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Code is wrong in their inference or lack there of I think yet again...
 
A 20 amp circuit for a bathroom makes sense, you could be powering a hair dryer, lights, exhaust fan, curling iron, makeup mirror, radio and what ever else your significant other or kids have plugged in.
 
infinity said:
A 20 amp circuit for a bathroom makes sense, you could be powering a hair dryer, lights, exhaust fan, curling iron, makeup mirror, radio and what ever else your significant other or kids have plugged in.
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20 amps is also a good idea in a kitchen when you have a microwave, toaster, rice cooker, air fryer, hot skillet, and a bunch of other crap on 2 circuits.
 
infinity said:
A 20 amp circuit for a bathroom makes sense, you could be powering a hair dryer, lights, exhaust fan, curling iron, makeup mirror, radio and what ever else your significant other or kids have plugged in.
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Right, if you use the code exception in 210.11 C 3.
 
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