The authenticity of solar panels can be determined by assessing several key indicators: 1. Certification validity, 2. . One of the most important steps of the permitting process of a photo voltaic system is the signage and labeling that identifies the existence of electrical components in the vicinity. 56, both off-grid and grid-tied systems are required to have permanent plaques or. . This is an introductory article on permit and safety requirements for signage and labeling for solar photovoltaic systems. The Guide also covers ANSI Z535. 4-2011, the standard for the. . Code-Making Panel 4 of the National Electrical Code recently completed its final changes to the NEC2026 code for articles related to labeling within the solar industry including PV labeling requirements. 31 (G) (4) to require the labels to be reflective, and all letters capitalized. The height of the letters shall be a minimum height of. . f a small solar panel and a small light or motor.