A feeder supplying a lighting and appliance panelboard is sized by adding which percentages for noncontinuous and continuous loads?

A feeder supplying a lighting and appliance panelboard is sized by adding which percentages for noncontinuous and continuous loads?

• A. 80% of the noncontinuous load and 100% of the continuous load
• B. 100% of the noncontinuous load and 100% of the continuous load
• C. 100% of the noncontinuous load and 110% of the continuous load
• D. 100% of the noncontinuous load and 125% of the continuous load

Answer: (D)

Sizing feeder demand uses a straightforward rule: treat noncontinuous loads at their full rating, and multiply continuous loads by 1.25 (125%) because they run for extended periods and require extra capacity to prevent overheating. This means you sum the noncontinuous portion at 100% plus 125% of the continuous portion to determine the feeder size. In this case, that approach matches the correct choice: take all noncontinuous loads at 100% and all continuous loads at 125%. The other options would under- or over-estimate capacity and could lead to undersized feeders or unnecessary oversizing.

Sizing feeder demand uses a straightforward rule: treat noncontinuous loads at their full rating, and multiply continuous loads by 1.25 (125%) because they run for extended periods and require extra capacity to prevent overheating. This means you sum the noncontinuous portion at 100% plus 125% of the continuous portion to determine the feeder size.

In this case, that approach matches the correct choice: take all noncontinuous loads at 100% and all continuous loads at 125%. The other options would under- or over-estimate capacity and could lead to undersized feeders or unnecessary oversizing.