Solar-Specific Hazards
Unlike conventional electrical systems, PV arrays are always energized during daylight — you cannot simply "turn off" the sun. This creates unique safety challenges for installers, firefighters, and maintenance personnel.
Arc Fault Protection
DC arc faults are a leading cause of PV fires. Series arcs occur from loose connections; parallel arcs from damaged insulation. NEC 690.11 requires arc-fault circuit interrupters (AFCI) on all rooftop PV systems ≥80V DC.
Rapid Shutdown
NEC 690.12 mandates that PV system conductors within 1 ft of the array boundary must drop to ≤80V within 30 seconds of shutdown initiation. Module-level power electronics (MLPE) like optimizers and microinverters satisfy this requirement.
Firefighter Safety
Clearly label all PV disconnects. Maintain 3-ft access pathways on roofs. Document system layout for first responders. Consider using non-conductive tools for emergency panel removal.