Code Change Summary: Revised language to clarify equipment accessibility.

In the 2020 NEC^®, Section 690.4(F) stated that electronic power converters (inverters, dc-to-dc converters, and electronic charge controllers) and their associated devices shall be permitted to be mounted on roofs or other exterior areas that are not readily accessible. The way the language was written prohibited inverters from being installed at interior areas that are not readily accessible for no apparent reason.

According to the definition in Article 100, Something is readily accessible if it is capable of being reached quickly for operation, renewal, or inspections without requiring those to whom ready access is requisite to take actions such as to use tools (other than keys), to climb over or under, to remove obstacles, or to resort to portable ladders, and so forth.

In the 2023 NEC^®, a public input was accepted to change the language in 690.4(F). Areas “not readily accessible” can exist on the exterior or interior of a building or structure. The existing NEC^® requirements for a PV system disconnect in 690.13, or a PV equipment disconnect in 690.15, or the rules on disconnecting power production sources for interconnected PV systems in 705.20 make it irrelevant whether a non-readily accessible electronic power converter is located outside or inside of a building or structure.

In the 2023 NEC^®, the word “exterior” was deleted from section 690.4(F) to make it clear that electronic power converters (such as a PV inverter) and their associated devices are permitted to be mounted on roofs or other areas that are not readily accessible.

It is likely that this section in the 2026 NEC^® will shorten the requirement further and simply state that electronic power converters and their associated devices are not required to be readily accessible.

Below is a preview of the NEC^®. See the actual NEC^® text at NFPA.ORG for the complete code section. Once there, click on their link to free access to the 2023 NEC^® edition of NFPA 70.