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Service Entrance Sizing

Size a residential service entrance per NEC 220.82. Enter your total calculated load and dwelling area.

Sum of all calculated loads from NEC Article 220

Conditioned floor area (NEC 220.82 applies 3 VA/sqft for general lighting)

Recommended Service Size

100A

Sufficient for small homes under 1,000 sqft with basic loads. Minimum per NEC for new construction.

Calculation Detail

  • General lighting load (2,000 sqft × 3 VA / 240 V): 25.0 A
  • Input load: 100 A
  • Controlling load (larger of the two): 100.0 A

Reference: NEC 220.82 (standard method for service entrance) • NEC Article 220 (load calculations) • General lighting: 3 VA/sqft at 240V

For reference only. Verify with your local building code and a licensed professional before making decisions.

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