What is the purpose of using demand factors in load calculations?

• A. To oversize service equipment.
• B. To size service equipment and feeders more realistically.
• C. To ignore variability.
• D. To decrease safety margins.

Answer: (B)

The purpose of demand factors is to reflect that loads don’t all reach their maximum at the same time. By applying a demand factor to the connected load, you size service equipment and feeders for the realistic maximum simultaneous demand rather than the sum of all nameplate ratings. This makes the system cost-effective and practical while still meeting reliability and safety requirements. Without demand factors, you’d end up oversizing equipment for a worst-case where every device is at full load together. The other options miss the point: demand factors reduce, not ignore, variability; they don’t aim to decrease safety margins—they help achieve appropriately sized equipment that handles actual usage.