Circuits for the things on the end of the wiring — motors, welders, generators and special locations.
Equipment circuits break the ordinary rules. A motor draws six times its running current for a few seconds at start; a welder has a duty cycle that means it never draws its nameplate figure continuously; a generator has to absorb a starting surge without collapsing.
Sizing these on nameplate current alone produces a circuit that either trips constantly or is dangerously oversized.
Full-load amps from the code tables, not from the nameplate — which is what the protection rules are written against.
Branch protection and overload are two different devices with two different rules.
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NEC 630, where duty cycle lets the conductor be smaller than the nameplate current suggests.
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Running load plus the largest single starting surge — not the sum of every surge.
Sizing the transfer switch for the load it actually has to carry.
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NEC 680 — special location rules, bonding and GFCI protection.
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What size generator you actually need — running watts plus the largest single starting surge, derated for altitude and heat. Not the sum of every surge, which is how most calculators oversize you.
FLAFull load current from motor kW or hp, including efficiency — the term most calculators drop, which understates the current by 10–15%.
2 calculators in this category. Every one is free to use on ElectroCalculators, with no account required, and every result cites the standard it came from.