With the large‑scale deployment of distributed and utility‑scale photovoltaic systems, high‑power solar modules have become mainstream, alongside 1000 V and 1500 V high‑voltage DC systems. As long as sunlight is available, the PV DC side remains energized. Unlike AC circuits where arcs self‑extinguish at current zero‑crossing, DC faults can generate persistent electric arcs — the leading cause of PV plant fires. Statistics show most photovoltaic fires originate on the DC side. Failures in combiner boxes, DC cables, connectors, DC disconnectors and surge protective devices (SPDs) create safety hazards and financial losses for residential, commercial‑industrial and utility‑scale installations. Effective DC‑side risk control, robust lightning protection and proper DC component selection are critical throughout design, procurement, installation and O&M of PV projects.