Circuit Panel Capacity?

F1nut

With that said, I have always wondered why 20 amps? I doubt the average rig doesn't pull anywhere near that even when cranked, so why not 15 amps?

The NEC requires a 20% margin on the breaker, so while a 15 amp breaker is capable of 1800 watts the max draw is restricted to 1440 watts. You add up the potential max draw of your gear and if it exceeds 1440 watts you should use a 20 amp breaker along with at least 12 gauge wire. Even better, use 10 gauge.

With your current 10 amp/1200 watt capable breaker the max draw would be restricted to 960 watts. If your current wire is at least 14 gauge you can simply change the breaker to a 15 amp and still meet code.

disneyjoe7

Agreed all of the above.

Glen B

It is important to understand the correct implementation of household circuit breaker derating rules. Breakers are rated for 100% of their rating, but because of concerns about the effects of heat generation from continuous loads (i.e., loads that run uninterrupted for 3 or more hours) the NEC/NFPA requires 80% derating for such loads.

Loads that are not continuous (i.e., run uninterrupted for less than 3 hours) are not subject to an 80% derating, and may be up to 100% of the breaker rating. Air conditioners, refrigerators, lighting, single appliances that draw at least 80 percent of the circuit capacity are considered continuous loads. Microwaves, toasters, most audio/video equipment, etc., are not considered continuous loads.

Pure class A amplifiers that draw their maximum current continuously would be subject to the 80% rule if they draw 12A or 16A. Class AB and other classes that draw their maximum current on peaks, are not a continuous load. There may be exceptions, use common sense. I have power tools like my miter saw and air compressor that are rated at 15 running amps and run on a 15A circuit. These tools run for only seconds to a couple of minutes respectively and are not subject to the 80% rule.

Speedskater

"Glen" that's a very good explanation. There is so much confusion between 'continuous', 'maximum' and 'rated' currents.