HOLT Electricians Practice Exam

For elevator systems, what is required separately for the elevator car lights and other power sources?

1. Power supply unit

2. Branch circuit

3. Auxiliary transformer

4. Backup generator

The correct answer is: Branch circuit

The requirement for a separate branch circuit for the elevator car lights and other power sources is essential due to safety and operational standards in electrical systems. A branch circuit is a part of the electrical system that distributes power from the main service panel to specific equipment or areas. Elevator systems must have dedicated circuits to ensure that the power supply to the elevator car lights is reliable and can operate independently from other systems. This ensures that in the event of an electrical fault or overload in one circuit, other circuits – such as those for the elevator itself – remain functional. This design promotes safety, reduces the risk of system malfunctions, and helps maintain the proper functioning of emergency systems like lighting in the event of a power failure. Other power sources, like the elevator's motor, also require specific power provisions, but they might not need to share the same branch circuit as the lighting system within the car, emphasizing the need for separate circuits to manage the loads and functionalities effectively.