NEC (National Electrical Code) Article 250 covers grounding and bonding for electrical installations to protect from electrical shock and ensure correct operation of the electrical system. Sometimes if I have a 3 or 4-gang plastic nail-on switch box that has a bunch of NM cables, when I'm making up the box rather than using a big blue wire-nut for my grounds I'll separate the grounds into 2 groups and use red/tan wirenuts instead, especially if there's 2 circuits in the box. Image used courtesy of Pixabay. Separable. If you're working with electrical systems, you know that grounding isn't just some bureaucratic requirement—it's literally the difference between a safe, functional system and a potential disaster. Circuits are grounded to limit excessive voltage from lightning, transient surges, and unintentional contact with higher voltage lines, and to limit the voltage to ground during normal operation. An equipment grounding conductor passing through the box without a splice is not required to be joined inside the box to others that are spliced in the box. During fault conditions, low impedance results in high fault current flow, causing overcurrent protective.
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