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A dwelling has a floor area of 1500 sq ft, with unfinished cellar not adaptable for future use, unfinished attic, and open porches. Appliances are a 12-kW range and a 5.5 kW, 240-V dryer. Assume range and dryer kW ratings equivalent to kVA rating in accordance with 220.54 and 220.55. What is the total net calculated load for the dwelling in VA units. (Annex D, example D1(a) One Family Dwelling)

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The total net calculated load for the dwelling, in VA units, is 17,500 VA.

To calculate the total net calculated load for the dwelling in VA (Volt-Amperes) units, you can follow the steps provided below, referring to Annex D, example D1(a) for a One Family Dwelling in the National Electrical Code (NEC):

1. Identify Appliances:

- You have two appliances: a 12 kW range and a 5.5 kW, 240-V dryer. These appliances will contribute to the total load.

2. Convert kW to kVA:

- According to NEC 220.54 and 220.55, you can assume that the kW ratings are equivalent to kVA ratings for these appliances.

- The range's kVA rating is 12 kVA (since it's equivalent to 12 kW).

- The dryer's kVA rating is 5.5 kVA (since it's equivalent to 5.5 kW).

3. Apply Demand Factors:

- Annex D, example D1(a) provides demand factors to apply to various loads in a one-family dwelling.

- In this example, a demand factor of 100% is applied to the range and dryer.

4. Calculate the Load:

- Start by adding the kVA ratings of the range and dryer since their demand factors are 100%:

Total load = (12 kVA) + (5.5 kVA) = 17.5 kVA

5. Convert to VA:

- To express the load in VA, simply multiply by 1,000 (since 1 kVA = 1,000 VA):

Total load in VA = 17.5 kVA * 1,000 VA/kVA = 17,500 VA

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