NEC Commercial Electrical Practice Test

How is the show window area measured for determining the number of receptacle outlets required above it?

1. Horizontally at maximum height

2. Horizontally at maximum width

3. Diagonally at minimum height

4. Vertically at maximum length

The correct answer is: Horizontally at maximum width

Measuring the show window area horizontally at maximum width is the correct approach for determining the number of receptacle outlets required above it. This method aligns with the NEC (National Electrical Code) standards, which aim to ensure that electrical installations are practical and meet safety requirements. When assessing the show window area, the horizontal width measurement accurately reflects the section of the display that will require power. This width is crucial because it establishes the relevant area for which receptacles are needed to ensure an adequate number of outlets for lighting and displays. Using maximum width ensures that the entire area being showcased is considered, facilitating proper electrical service for all display needs. The other measurement options do not provide the clarity and alignment with NEC requirements needed for effective outlet placement. For instance, measuring at minimum height or vertical length does not give an accurate representation of the display area where outlets are necessary. Diagonal measurements could also create confusion as they do not conform to the standard measurements of area defined in the NEC, which seeks to maintain consistency in electrical installations.