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. Grounding techniques and National Electrical Code requirements for systems and equipment operating at more than 1,000V, such as 5-kilovolt (kV) and 15-kV systems, differ slightly from those for systems of 1,000V or less. In factories, construction sites, and even commercial buildings, this question pops up all the time. Your boss might insist on it, while your. This section explains that Article 250 focuses on general grounding and bonding electrical installation requirements, including: The grounding of systems, circuits, and equipment. These two arrangements, with their system voltage relationships, are shown in Wye and Delta Winding Configurations and. The grounding system provides a low-impedance path for fault current and limits the voltage rise on the normally non-current-carrying metallic components of the electrical distribution system.
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