NALMCO Certified Apprentice Lighting Technician (CALT) Practice Exam

A Class P ballast is one which contains what feature?

1. A beeper to call you when there's a problem

2. A thermal protection device that shuts down the ballast if it overheats

3. A device that allows the ballast to start lamps at cold temperatures

4. None of the above

The correct answer is: A thermal protection device that shuts down the ballast if it overheats

A Class P ballast is specifically designed with a thermal protection device. This feature is critically important as it ensures the ballast can shut down if it overheats, preventing potential damage and enhancing safety. The thermal protection mechanism helps to protect other components of the lighting system and minimizes fire hazards associated with overheating. While other features might be useful for ballasts in general, they do not define the core functionality of a Class P ballast. For example, starting lamps at cold temperatures is an important function, but it is not a distinguishing feature of Class P ballasts. Thus, the identification of thermal protection as a key characteristic underscores the ballast's emphasis on safety and reliability in various operating conditions.