Technical Article

Code Corner: 2023 NEC Article 691 Large-Scale PV


In this installment of our Code Corner series, Ryan Mayfield takes up the scope, special requirements, and engineering design for large-scale PV systems not owned and operated by utilities (i.e., 2023 NEC Article 691).

Display of PV Arrays followed by interactive inverters, a transformer, a substation, and them to the utility grid.

Section 691.4 enumerates key compliance details – access, markings, voltage ranges, monitoring – for PV systems with a minimum of 5 MWac of inverter generating capacity.  Section 691.6 provides the documentation any proper engineer-stamped system design ought to have. 

Check out Ryan’s 8-minute explanation of the most relevant portions of Article 691:

You can also find more of our Code Corner videos on the Mayfield Renewables YouTube channel. Contact us to start a project or learn more.

Consulting Engineering

Two solar engineers review electrical control panel during professional system inspection.

Our professional services cover every stage from feasibility to commissioning for commercial & industrial (C&I), microgrid, and small utility-scale projects.

Education & Training

Audience attends solar and microgrid engineering education summit presentation in modern conference auditorium.

Mayfield's experts fulfill our commitment to educational excellence by presenting black-and-white technical concepts in dynamic, living color.

Technical Articles

Solar and microgrid engineers at Mayfield Renewables review detailed construction blueprints during collaborative project planning.

We transform complex topics into actionable insights through high-quality digital content focused on codes, standards, and best practices.