Originally Posted by ramnet
16 amps continuous load times 1.25 allowed spike load is, guess what? 20 amps - the size of the breaker.
Nope, that's wrong. If you continually use 16a, it means you REQUIRE a 1.25 times sized circuit / breaker in order to be allowed to do that, leaving ZERO room for bursting on a 20a circuit. If, however, you have ZERO continuous load, you may then use the entire circuit size for your non continuous load.
Multiply continuous load times 1.25
add non continuous load
Result of the two added together must be less than rated circuit / breaker size.
In my case, I'm never using under 14a on that circuit, so there is no room for argument that my continuous load is under 14a. 14 times 1.25 = 17.5. If I'm using a 20a breaker, this means there is 2.5a "left over" for non continuous loads, which would mean, a total of 16.5a.