/diy/ - Do It Yourself

>>1743346
The circuit capacity isn't defined by the continuous load limit of the breaker, but the intermittent rating. You don't go and buy a 12.5A breaker. You buy a 15A one. You look up 15A in your NEC book and find 14ga specified. You don't have to derate anything unless you're running lots of wires in a conduit or are otherwise expecting a high ambient temperature.
You can for sure draw 20A on a 20A circuit. You can draw that for several minutes in most cases, and might even be able to draw it for ten minutes or more depending on the ambient temp. You can even draw 40-60A out of most 20A breakers for a few seconds. This behavior is required to prevent nuisance tripping when motors kick on. The absolute instant-trip limit of a breaker depends on the design, but it's usually around 10x the intermittent rating. After that the trip time is measures in single digit milliseconds or microseconds.

>>1262665
The lamp heats up very quickly so the 5 amps last for only a moment.
Breakers have a delay built in. The over-current has to last for a predetermined time based on how much current is drawn.
With your kiln unplugged and turned ON, measure the resistance at the plug.
If the kiln is digital it may not have resistance until the controller is activated by the 120ac but it's worth a try.

>>1260863
breakers have a time/current trip profile
a certain amount of current has to flow for a certain period of time to trip the breaker
if the over-current wasn't sever enough for long enough the breaker won't trip