Article 690 of the National Electrical Code (NEC) establishes the safety and installation requirements for photovoltaic (PV) systems in the United States. The 2023 NEC introduces critical updates to Article 690 that directly impact how solar installers design, label, and connect residential and commercial solar installations to meet Authority Having Jurisdiction (AHJ) inspection requirements.
Key NEC 2023 Article 690 changes include:
- Terminology update: “PV output circuit” replaced with “PV string circuit” (690.7A)
- Rapid shutdown requirements: Enhanced labeling and safety protocols (690.12D)
- Grounding and bonding: Expanded specifications for equipment grounding conductors (690.43)
- Arc-fault protection: Strengthened AFCI standards for fire safety (690.11)
- Cable tray rules: Updated rooftop installation requirements (690.31C2)
- Source connections: Stricter splice and tap requirements (705.11)
- Energy storage commissioning: Mandatory testing and documentation procedures (Article 706.7)
- Floating solar systems: New requirements for floatovoltaic installations (690.4F)
The 2023 NEC solar code updates affect conductor sizing, overcurrent protection device selection, labeling terminology, and energy storage system integration. Installers must update plan sets, equipment selections, and installation methods to align with these revisions, as many AHJs nationwide have already adopted NEC 2023 standards for permit approval. Compliance with these updated requirements prevents inspection failures, reduces costly redesigns, and accelerates permission to operate (PTO) timelines.
Understanding Article 690 updates ensures solar installations meet current electrical safety standards while maintaining code compliance throughout residential, commercial, and utility-scale PV projects.
NEC 2020 vs 2023: Critical Solar Code Revisions
| Code Section | NEC 2020 | NEC 2023 |
|---|---|---|
| Terminology | “PV Output Circuit” | Now “PV String Circuit” |
| PV Labeling | Basic labels with limited standardization | Standardized, clearer labeling mandated |
| Rapid Shutdown (RSS) | Basic array shutdown protocols | Enhanced safety and labeling specifications |
| Grounding & Bonding | General guidance | Expanded requirements (690.43) |
| ESS Commissioning | Limited guidance | Defined commissioning protocols (706.7) |
| Arc-Fault Protection | Standard AFCI requirements | Strengthened AFCI standards (690.11) |
| Cable Tray Rules | Basic guidance | Refined rooftop tray specifications |
| Splices & Taps | General connection standards | Stricter source connection rules (705.11) |
| Floatovoltaics | No provisions | New floating PV requirements (690.4F) |
