What marking requirement is specified for junction boxes in Article 690?

Junction boxes associated with photovoltaic (PV) systems must be marked to indicate their connection to the PV system as stipulated in Article 690 of the National Electrical Code (NEC). This requirement is crucial for several reasons.

Firstly, proper marking facilitates the identification of components that are part of the PV system, which is essential during maintenance, inspection, and emergency situations. It helps ensure that any workers or technicians interacting with the system are aware that they are working with solar technology, which can have different voltage and safety considerations compared to conventional electrical systems.

Secondly, marking junction boxes contributes to the overall safety of the electrical installation. By clearly identifying these junction boxes as part of a PV system, it reduces the risk of accidental disconnection or interference with the solar equipment, which could lead to inefficiencies or safety hazards.

These marking requirements are aligned with the NEC's objective of promoting safety and ensuring clear communication about the systems in use. Thus, the marking directly enhances the reliability and safety of PV system installations.