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    NEC Motor Circuit Sizing Calculator (Article 430)

    Why does the motor calculator use table FLC instead of the nameplate amps?

    NEC 430.6(A)(1) requires that branch-circuit conductors, the short-circuit/ground-fault device, and the disconnect be sized from the full-load current values in Tables 430.247, 430.248, and 430.250, not the motor nameplate FLA. The nameplate FLA is used only for overload protection sizing under 430.32. This calculator follows that split, taking the table FLC for everything except the overload.

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    Use the NEC Motor Circuit Sizing Calculator (Article 430) to get an exact answer for your inputs.

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    Estimates and general guidance only. Verify against your local code and AHJ before any installation. Gas, electrical, and refrigerant work is hazardous to untrained users.

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