Article 430 · conductor, OCPD and EGC
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Worked example — for a 10 HP 460 V three-phase squirrel-cage motor on an inverse-time breaker, copper, the engine returns:
14 AWG conductors — FLC 14.0 A · OCPD 35 A · EGC 10
How it works. Motor circuits are sized from the table full-load current, not from the nameplate, and the conductor, the overcurrent device and the overload protection each follow different rules. That is why the branch-circuit device can be far larger than the conductor would normally allow — it is there for short circuits and ground faults, while overload is handled separately.
What this covers: Article 430 induction/synchronous/DC motors. NOT for hermetic AC compressors — those use Article 440 nameplate MCA/MOP, not Table FLC. No VFD or multi-speed path.
Educational reference, not code. Based on NEC (NFPA 70) 2023 (430.22 · 430.52 · 430.32). Your state or local AHJ may enforce a different edition or amend it — theirs is the one that counts. No NEC text is reproduced here.