NEC Dwelling Service Load Calculator (220.82)

What is the difference between the standard and optional dwelling load methods?

The Standard method follows NEC 220 Part III, applying separate demand factors such as 220.42 for general lighting, 220.53 for fastened-in-place appliances, and 220.55 for the range. The Optional method under 220.82 instead takes the first 10 kVA at 100% and the remainder at 40%, with heating or air conditioning added separately. This calculator computes both so you can use the smaller compliant service size.

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