Should the calculated load of a feeder or service be equal to or greater than the sum of the loads on the branch circuits supplied?

The calculated load of a feeder or service should indeed be equal to or greater than the sum of the loads on the branch circuits it supplies. This ensures that the feeder or service has enough capacity to handle the total demand without overloading. Following the National Electrical Code (NEC), the design of electrical systems must consider not just the amount of load currently being used, but also potential increases and variations in load. By sizing the feeder or service appropriately, it ensures safety and reliability, preventing overheating and possible failures.

Under-sizing the feeder or service can lead to voltage drops, equipment damage, and increased fire risk due to overheating of conductors. Adequate capacity allows for normal variations in load and helps accommodate future expansions or additional loads that might be added to the system. Therefore, ensuring that the calculated load meets or exceeds the sum of the branch circuit loads aligns with best practices in electrical design and safety standards.