Are neutral loads permitted for feeder or service conductors in schools using optional calculations?

Neutral loads are permitted for feeder or service conductors in schools when employing optional calculations per the National Electrical Code (NEC). The reason for this allowance is that optional calculations provide a more flexible method for determining the size of conductors based on the actual load conditions rather than strict requirements. This adaptability can lead to more efficient use of materials and energy by allowing designs that account for the specific load characteristics of educational facilities.

In schools, optional calculations take into consideration the diversity of loads, meaning that not all circuits will be operating at their maximum capacity simultaneously. By including neutral loads in these calculations, designers can create a more accurate representation of the electrical needs of the school, which enhances safety and efficiency. This permitted approach aligns with the NEC's goal of ensuring that electrical installations are safe and fit for purpose while also being adaptable to the specific environmental contexts in which they are installed.