Panel Loading and Phase Rebalance

Per-phase totals, percent imbalance, and a swap suggestion to minimize neutral current.

Run the calculator

Example

You enter

You get

Details, formula, and sources

Companion to voltage-imbalance.

Per-phase total = sum of single-leg circuits on phase. Imbalance % = (max - min) / mean × 100. Greedy swap suggestion: move heaviest single-leg circuit on the heaviest phase to the lightest phase if the projected imbalance is reduced.

NEC 2023 (NFPA 70). §220 (load calculations) and §408.36 (panel rating). NEMA MG-1 by name for the imbalance / horsepower derate cited adjacent to the result.

Free read-only access at nfpa.org/freeaccess.

Estimate. AHJ and licensed electrician govern. Verify against the NEC edition adopted in your jurisdiction.

Field names used by the API: circuits, totals_A_amps, totals_B_amps, totals_C_amps, mean_amps, imbalance_pct

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