Which of the following statements about overcurrent protective devices in panelboards is accurate?

The accurate statement regarding overcurrent protective devices in panelboards is that they are either low-voltage power circuit breakers (LVPCBs) or fuses. This reflects the variety of devices used to protect electrical circuits from excessive current that can lead to overheating and potential fire hazards.

Fuses operate by melting a conductor inside to interrupt the flow of current when it exceeds a predetermined level, while LVPCBs can be reset and offer more features, such as the ability to select different trip settings and provide additional functionality like metering and control. The inclusion of both types of devices in panelboards offers flexibility to accommodate various application requirements and configurations.

Recognizing that overcurrent protection is critical for safety and compliance with electrical codes, the statement that they are only fuses is inaccurate, as it overlooks the inclusion of circuit breakers. Similarly, stating that they consist of circuit breakers only fails to acknowledge the important role fuses play. The mention of switches being excluded from this category is also incorrect, as switches serve different functions in electrical systems and are not classified as overcurrent protective devices.