Circuit breakers are classified by what criterion?

Circuit breakers are classified primarily by their ampere rating because this determines the maximum current the breaker can handle before tripping. The classification by ampere rating is crucial in ensuring that the breaker is suitable for protecting the particular circuit it governs, effectively preventing overloads and potential electrical fires. The ampere rating must match the specifications of the electrical system it is designed to protect, providing a balance between allowing normal operation while mitigating the risk of damage under fault conditions.

The other options, such as the type of circuit it protects, the brand name of the manufacturer, and the color of the circuit breaker, do not offer a universal classification criterion. While different types of circuit breakers may be designed for specific applications or circuits, these distinctions are secondary to the primary classification based on ampere rating, which directly impacts safety and functionality. Brand names and colors may vary widely without any governing classification principle related to performance or safety standards in electrical systems.