What is the minimum feeder demand for a 17 kW range?

What is the minimum feeder demand for a 17 kW range?

• A. 8 kW
• B. 10 kW
• C. 17 kW
• D. 21.25 kW

Answer: (B)

The main idea here is that the feeder load for a cooking appliance like a range is not taken as its full nameplate rating. Electrical design uses a demand factor for ranges so the feeder isn’t oversized, reflecting that not all elements of the range operate at full power at the same time. For a single electric range, the NEC provides a table that gives a minimum feeder demand based on the range’s rating. For a 17 kW range, that table results in a minimum feeder demand of 10 kW. This is why 10 kW is the best answer: it represents the code-supported feeder load you must size for, rather than the full 17 kW or any larger multiplier. The other options either understate the required feeder size for this range or reflect applying a full-nameplate multiplier (which the minimum feeder demand is specifically designed to avoid).

The main idea here is that the feeder load for a cooking appliance like a range is not taken as its full nameplate rating. Electrical design uses a demand factor for ranges so the feeder isn’t oversized, reflecting that not all elements of the range operate at full power at the same time. For a single electric range, the NEC provides a table that gives a minimum feeder demand based on the range’s rating.

For a 17 kW range, that table results in a minimum feeder demand of 10 kW. This is why 10 kW is the best answer: it represents the code-supported feeder load you must size for, rather than the full 17 kW or any larger multiplier. The other options either understate the required feeder size for this range or reflect applying a full-nameplate multiplier (which the minimum feeder demand is specifically designed to avoid).