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Calcimator

Electrical Load Calculator

Calculate total electrical load by circuit type and determine the service panel size and main breaker needed.

Inputs

W
W
W
W

Results

Total Connected Load

29,000 W

≈ 4 EV chargers

Total Amps (240V)120.8 A
NEC Demand Load17,600 W
Demand Amps (240V)73.3 A
Panel Size100 A
Main Breaker100 A
Total Circuits16
How to Use This Calculator
  1. Enter the number of Lighting Circuits and Watts per Lighting Circuit.
  2. Add Outlet Circuits and Watts per Outlet Circuit.
  3. Enter Appliance Circuits and Watts per Appliance Circuit.
  4. Add HVAC Circuits and their wattage.
  5. Review the Total Load (amps) to size the service panel or subpanel required.

How the result changes with Appliance Circuits

Appliance CircuitsTotal Connected Load
121,000 W
3.531,000 W
6.543,000 W
953,000 W

What each input means

Lighting Circuits
Number of dedicated lighting circuits.
Watts per Lighting Circuit
Average wattage per lighting circuit.
Outlet Circuits
Number of general-purpose outlet circuits.
Watts per Outlet Circuit
Average wattage per outlet circuit.
Appliance Circuits
Number of dedicated appliance circuits (oven, dryer, etc.).
Watts per Appliance Circuit
Average wattage per appliance circuit.
HVAC Circuits
Number of HVAC or heat pump circuits.
Watts per HVAC Circuit
Wattage per HVAC unit.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Lighting Circuits = 4, Watts per Lighting Circuit = 600, Outlet Circuits = 8, Watts per Outlet Circuit = 1200 = 8 input(s) provided
  2. Calculate Total Connected Load
    Total Connected Load
    29000 = 29000
  3. Calculate Total Amps
    Total Amps
    120.8 = 120.8
  4. Calculate NEC Demand Load
    NEC Demand Load
    17600 = 17600

Engine last updated .

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