Hint: Whoops! Where’s the bushing?
Prior to 2023, Sec. 300.4(G) did not prohibit a plastic insulating bushing from being installed after the conductors were installed. But Sec. 300.4(G) was revised for 2023 and now requires conductors 4 AWG or larger installed in raceways to be protected prior to the installation of the conductors. This conductor protection can be in the form of a fitting with a smoothly rounded insulated surface such as a plastic bushing, a listed metal fitting with smoothly rounded edges, separation from the fitting or raceway with insulating material securely fastened in place, or threaded hubs or bosses that are part of the enclosure providing a smoothly rounded or flared entry for conductors. Installing a plastic bushing after the conductors have been installed is now a Code violation, so don’t forget to install the bushings before the conductors are pulled in. Also, remember to take extra care when pulling the conductors in so as to not damage the bushing or the conductors.
