DIYbanter - View Single Post - 15 amp rated light switch and outlets on a 20 amp circuit breaker

Ralph Mowery

In article ,
says...

Switches should be sized to the load but 15a receptacles are actually
rated to pass through 20a. The listing on any equipment using a 15a
(NEMA 5-15) plug should be limited at 12a or 80% of 15a. I have seen
some non-compliant equipment but it is rare. Usually the labeling is
bogus, like those "1800 watt" hair dryers that are actually more like
1400w.

I have measured the same thing on several devices. Maybe that is the
peak wattage as inthe first few miliseconds it drawa that power. Sort
of like the 'music power' of speakers. I have seen computer speakers
that show 50 watts or better powered by a small wall cube. Inside the
speaker is rated for 2 watts. Maybe the first milisecond when a drum is
hit the power will spike that high.