Which statement about load calculations and feeders is true?

Which statement about load calculations and feeders is true?

• A. They are based only on connected loads.
• B. They ignore demand factors.
• C. They are based on connected loads and demand factors.
• D. They apply only to service equipment, not feeders.

Answer: (C)

The essential idea is that sizing feeders and service equipment is done using both the connected load and demand factors. You start with the total of loads that could be connected, but you don’t simply add them up as if all would run at once. Demand factors (and diversity) adjust that total to reflect typical usage, giving a calculated load that the feeders and conductors must be sized to carry. This shows why the correct statement is that calculations are based on connected loads and demand factors. It also helps explain why the other options aren’t right: relying only on connected loads overstates the load, ignoring demand factors would underrepresent practical load, and the method applies to feeders as well as services, not just service equipment. Continuous loads are still treated with the higher ampacity required (often 125% of the continuous load) to ensure safe operation.

The essential idea is that sizing feeders and service equipment is done using both the connected load and demand factors. You start with the total of loads that could be connected, but you don’t simply add them up as if all would run at once. Demand factors (and diversity) adjust that total to reflect typical usage, giving a calculated load that the feeders and conductors must be sized to carry. This shows why the correct statement is that calculations are based on connected loads and demand factors. It also helps explain why the other options aren’t right: relying only on connected loads overstates the load, ignoring demand factors would underrepresent practical load, and the method applies to feeders as well as services, not just service equipment. Continuous loads are still treated with the higher ampacity required (often 125% of the continuous load) to ensure safe operation.