NEC 코드 101: 전기 설비에 대한 전문가 가이드

Article 690 provides the installation requirements for solar photovoltaic (PV) systems, excluding large-scale utility PV systems (covered by Article 691). It governs the PV array circuits, inverters, controllers, disconnects, grounding, and interconnections—whether stand-alone, interactive with other power sources, or hybrid—producing either AC or DC power.

Key highlights include:

Scope and Applicability: Covers residential, commercial, and industrial PV systems except for utility-scale stations. Multiple PV systems are allowed on a single structure with appropriate labeling and directories.

Equipment Requirements: PV components (e.g., inverters, modules, combiner boxes, rapid shutdown systems) must be listed or evaluated for the specific PV application.

Circuit and Voltage Requirements: Limits DC voltage to 1000V (600V for one- and two-family dwellings); conductor ampacity and maximum circuit currents must be carefully calculated; special provisions apply to bipolar circuits and systems with multiple voltages.

Arc-Fault and Ground-Fault Protection: DC circuits over 80V must have arc-fault protection; ground-fault protection (GFDI) is required for systems over 30V or 8A unless exempted.

Rapid Shutdown: Required for PV circuits on or in buildings to ensure firefighter safety—exceptions apply to ground-mounted and non-enclosed structures like carports.

연결 해제 수단: PV systems must have clearly labeled and accessible means to disconnect from other electrical and storage systems.

Wiring Methods and Accessibility: PV conductors over 30V that are accessible must be enclosed (e.g., MC cable or raceways); power converters can be installed on rooftops if disconnecting means are accessible.

Floating PV Systems: Must be suitable for increased mechanical stress, corrosion, and humidity, and allow for expected movement on water.

접지 및 본딩: Allows functionally grounded, ungrounded, and solidly grounded DC circuit configurations with detailed grounding requirements for safety.

전문가 팁: Wait, besides NEC, are there other electrical codes to comply with? In the last article, we explained in detail about the types and code compliance of solar conduits. You can click on the text above to read more.