148 doesn't play favorites: The code mandates that all metallic parts of electrical boxes must bond to ground—no exceptions for cabinet doors. Bottom line: That door is part of the enclosure. Skip the grounding, and you're gambling with safety. Which NEC rules apply to electrical. Part V of NEC's Article 250 states the rules for bonding services, communication systems, other enclosures, hazardous (classified) locations, piping systems, exposed structural metal, and lightning protection systems. The neutral conductor is typically the grounded conductor connected to the system's neutral point, carrying current under normal operation., the neutral point of a wye-connected transformer and the phase on a corner-grounded delta connection. The purposes are to: ◦ limit overvoltages due to lightning, line surges, or. Equipment grounding must be done in accordance with the National Electrical Code (NEC).
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