Code Change Summary: Revised language makes it easier for PV systems sharing a common wireway.

In the 2023 NEC^®, Section 690.31(B) was revised and made into a list for ease of use.

Additionally, revised language now makes it easier for PV installations where multiple PV system equipment share a common wireway or enclosure.

In the past, PV system dc circuits were not permitted to occupy the same equipment wiring enclosure, cable, or raceway as other non-PV systems, or inverter output circuits, unless the PV system dc circuits were separated from other circuits by a barrier or partition or fell within the guidelines of the exception which did not apply to single-conductor PV wire or cable.

In the 2023 NEC^®, the revised exception in 690.31(B) applies more generally and no longer excludes single-conductor PV wire or cable.

The revised exception now applies where all conductors or cables have an insulation rating equal to at least the maximum circuit voltage applied to any conductor within the same wiring method. For these installations, the following shall be permitted:

(1) Multiconductor jacketed cables for remote control, signaling, or power-limited circuits shall be permitted within the same wiring enclosure, cable, or raceway as PV system dc circuits where all circuits serve the PV system.

(2) Inverter output circuits shall be permitted to occupy the same junction box, pull box, or wireway with PV system dc circuits that are identified and grouped as required by 690.31(B)(2) and (B)(3).

(3) PV system dc circuits utilizing multiconductor jacketed cable or metal-clad cable assemblies or listed wiring harnesses identified for the application shall be permitted to occupy the same wiring method as inverter output circuits and other non-PV systems.

According to the revisions, in a wireway installation containing PV system dc circuits and other non-PV circuits or other PV inverter output circuits (all rated for the maximum voltage present on any one conductor), without barriers or partitions in the wireway, code compliance can be achieved if the ac and dc conductors are properly grouped and identified.

Another method of code compliance for the above example in a wireway is for the PV system dc circuits to be installed using multiconductor jacketed cable or metal-clad cable assemblies.

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.