What is the maximum allowable voltage drop for secondary lighting main circuits?

The correct maximum allowable voltage drop for secondary lighting main circuits is 3%. This standard is based on ensuring that lighting systems operate efficiently and provide adequate illumination without significant loss of power. A voltage drop greater than this can result in dimmer lighting, which affects visibility and safety in environments where lighting is crucial.

Additionally, maintaining a voltage drop within this limit helps prevent excessive heat generated by electrical components, contributes to the longevity of the lighting fixtures, and enhances energy efficiency overall. Compliance with this standard ensures a reliable and effective lighting system that meets both functional and safety requirements in various applications.