What is a module circuit as defined in Article 690?

A module circuit, as defined in Article 690 of the National Electrical Code (NEC), refers to the conductors that connect a photovoltaic (PV) module to the inverter. This includes the wiring that carries the direct current (DC) generated by the solar panels to the inverter, where it is converted to alternating current (AC) for use in the electrical system. The importance of this definition lies in understanding how the electrical flow is managed from the solar modules, ensuring proper installation, safety, and code compliance in photovoltaic systems.

While other components like battery connections or electrical panel connections are essential parts of a solar energy system, they fall under different categories and definitions within the NEC. The module circuit specifically refers to the part of the system responsible for the immediate transition of energy between the solar modules and the inverter, emphasizing its role in enabling the effective transformation of solar energy into usable electrical power.