What does "breaking capacity" refer to in overcurrent devices?

Breaking capacity refers to the maximum current that an overcurrent device, such as a circuit breaker or fuse, can safely interrupt without failing. This characteristic is crucial because it determines the device's ability to clear fault conditions, such as short circuits, without causing damage to itself or the electrical system.

In practical terms, if a fault occurs that generates a current higher than the breaking capacity, the device may not be able to successfully interrupt the flow of electricity, which can lead to catastrophic failure, equipment damage, or even fire hazards. Therefore, understanding a device's breaking capacity ensures that it is appropriately rated for the specific applications and potential fault conditions it may encounter.

The other choices do not accurately represent the definition of breaking capacity, as they pertain to different aspects of overcurrent devices. For example, maximum voltage pertains to the electrical potential the device can manage, reaction time measures how quickly a device responds to overcurrent conditions, and cost relates to the economic value rather than to functional specifications.