Home Electrical Service Calculation
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Summary: The home electrical service size is based upon the electrical loads and the required circuits specified by the electrical codes as shown in this example. |
Electrical Service Calculations Process |
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| This electric service calculation is based on a single family home of 3000 square foot with the following electrical loads:
1- 12 kw electric range 20 kw of electric space heating (1 central elect. heating unit) 1- 5 kw electric water heater 1-central air conditioner, 9 kw 1- dishwasher, 1 kw 1- disposal, 0.9 kw 1- electric clothes dryer, 4500 watt |
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220-3a General Lighting, 3000 sq ft x 3 watts = 9000 -- 220-16a 2 Small Appliance, 1500 ea= 3000 -- 220-16b Laundry = 1500 -- Table 220-11 Total General Lighting, Small Appl., Laundry = 13500 -- Table 220-11 Apply Demands, 1st 3000 watts 3000 Table 220-11 Balance(10500 watts) at 35 percent 3675 220-18 Dryer (minimum 5k) 5000 220-19 Range (from col C) 8000 220-17 Add Fixed Appliance x 100 percent (not more than four) 6900 220-21 Larger of Heat / Air Conditioning 20000 VA Total 46575 Amps Divide by 240 (volts) = 194 310-15(b)6 200 Amp service wire: 2/0 copper
