Solar PV Systems & the 2020 NEC - Oregon Edition

Significant changes to articles 690.8, 690.9 and 690.12 will be reviewed including: Rapid Shutdown requirements, and the revision to the allowed methods for the calculation of circuit current to be based on the rated input current of the electronic power conversion equipment (i.e. inverter) as long as the overcurrent device protecting that circuit doesn’t exceed the conductor ampacity. Additionally, this code cycle addresses installations where overcurrent protection can be provided at the supply or load end of the circuit, with length limitations provided on those circuits.

Disconnecting Means reviews NEC articles 690.13 – 690.15 including PV equipment disconnect requirements, and labeling requirements. There were no significant changes included in Part 3 of Article 690 for the 2020 version, however one notable revision is the PV system disconnecting means must be locked if live parts are accessible to unqualified persons.

Grounding reviews NEC articles 690.41 – 690.50 including ground-fault protection, system grounding, equipment grounding & sizing, grounding electrode systems and continuity of equipment grounding. Notable changes include addressing ground-fault protection with DC to DC converters, and increases in EGC conductor size for voltage drop concerns are no longer required on any PV system conductor (AC or DC).

Markings reviews NEC articles 690.51 – 690.56 including proper PV system labeling, Identification of power sources. Changes include now AC modules, like standard PV modules, shall be marked according to their listing, DC PV circuit labels now only have to supply highest maximum voltage (current values no longer required here), and updated labeling requirements for rapid shutdown systems (now that the January 1, 2019 delayed implementation date has passed).

Significant changes include restructuring and a reduction in overall article, clarification on power source output circuits, and some new sections 705.11 (intended to provide more guidance on supply-side connections) and 705.13 which lists requirements for Power Control Systems used to control one or more power production sources, energy storage and other equipment.

Review the requirements for the installation of PV systems covered in articles 690, and 705 of the 2020 NFPA 70 – National Electrical Code and Oregon Electrical Specialty Code.