What is the maximum allowable voltage drop in a branch circuit according to NEC guidelines?

The National Electrical Code (NEC) provides guidelines for voltage drop in branch circuits to ensure efficient and safe operation of electrical systems. A maximum allowable voltage drop of 3% for branch circuits is recommended to strike a balance between performance and safety. This guideline helps maintain adequate voltage levels at the equipment and ensures that devices operate efficiently, minimizing the risk of overheating or failure due to insufficient voltage.

The 3% limit is particularly crucial in branch circuits that supply lighting and other critical loads, as excessive voltage drop can lead to poor performance and reduced efficiency. Maintaining the voltage drop within this limit is important for both the longevity of the electrical devices and the safety of the overall electrical system.

Other choices reflect different percentages but do not align with the NEC recommendations for branch circuits. While 5% is sometimes referenced as a total for feeders and branch circuits combined in certain applications, it exceeds the recommended percentage for branch circuits on their own. The lower limits of 2% may be seen in specific scenarios, but it's generally understood that the 3% figure is the practical maximum for ensuring optimal performance across the typical range of branch circuits.