Which NEC rules apply to electrical cabinet doors? Let's unpack a few key standards that apply: NEC 250. 148 (Grounding Conductor): Requires metallic junction boxes—and by extension, cabinet doors—to bond to ground using a designated grounding screw or clip. We'll blend insights from field experiences and code requirements to give you clarity you can actually apply—no technical jargon fluff. Why. Power from factory ground must be installed by a qualified electrician. Each DISTRIBUTION BOX and controller must be grounded. Grounding of the units: Attach a ground wire from one of. While the NEC provides clear descriptions of grounding and bonding in Art. 100, the words are often misused in the various articles. In the US, grounding and bonding are regulated by the National Electrical Code (NEC), while in the UK and Europe, they are guided by standards issued by the International Electrotechnical Commission (IEC) and national regulations such as BS 7671 (IET Wiring Regulations).