The neutral and ground must be separated at sub-panels but bonded using jumper wire at the main service panel. [1m:6s] Jumpers are specifically designed for this purpose but are not required in many cases. [1m:13s] If jumpers were unavailable, you could simply use a wire to make the same kind of. 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. I can. The National Electrical Code (NEC) provides comprehensive safety standards for electrical installations, including requirements for electrical panels (main service panels and subpanels or breaker box). NEC Article 408 covers switchboards, switchgear, and Panelboards installation and applications. Messy distribution boxes are dangerous and very hard to fix. You will learn to build a safe, efficient, and professional electrical system today. In order to better let everyone understand "jumper", let's take a look at a photo.
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