What is the minimum demand for a single branch-circuit serving one 4 kW cooktop and two 5 kW wall-mounted ovens?

What is the minimum demand for a single branch-circuit serving one 4 kW cooktop and two 5 kW wall-mounted ovens?

• A. 8,800 W
• B. 8,000 W
• C. 9,200 W
• D. 16,000 W

Answer: (A)

The concept being tested is how to size a single branch circuit for multiple cooking appliances using NEC demand factors. When you have more than one cooking appliance on the same branch, you don’t size the circuit for the full sum of all nameplate ratings. Instead, you apply a demand factor that reflects typical simultaneous use. For this case: one cooktop rated at 4 kW and two ovens at 5 kW each gives a total nameplate load of 14 kW. For three or more cooking appliances, NEC 220.55 uses a 63% demand factor. So the minimum demand load is 14 kW × 0.63 = 8.82 kW, which rounds to 8,800 W. This is why 8,800 W is the best answer: it represents the actual reduced demand used for sizing the branch circuit, not the full sum of all loads. The other values would correspond to different (incorrect) assumptions about the demand factor or simply summing all loads without applying the applicable table.

The concept being tested is how to size a single branch circuit for multiple cooking appliances using NEC demand factors. When you have more than one cooking appliance on the same branch, you don’t size the circuit for the full sum of all nameplate ratings. Instead, you apply a demand factor that reflects typical simultaneous use.

For this case: one cooktop rated at 4 kW and two ovens at 5 kW each gives a total nameplate load of 14 kW. For three or more cooking appliances, NEC 220.55 uses a 63% demand factor. So the minimum demand load is 14 kW × 0.63 = 8.82 kW, which rounds to 8,800 W.

This is why 8,800 W is the best answer: it represents the actual reduced demand used for sizing the branch circuit, not the full sum of all loads. The other values would correspond to different (incorrect) assumptions about the demand factor or simply summing all loads without applying the applicable table.