According to the NEC (National Electrical Code), all wire splices and electrical connections must be enclosed within an approved electrical junction box to ensure safety, accessibility, and code compliance. While junction boxes can be concealed within walls or ceilings (recessed), this discussion focuses on surface mounted junction boxes which are attached directly to the surface of a wall, ceiling, or other structural element. Understanding the different electrical junction box types helps electricians, engineers, contractors, and buyers. The junction boxes are supplemented by a range of optional equipment, making installation quick and easy. The boxes that are suitable for wet areas have been manufactured using a two-component technology and include membrane cable entries. The knock-out membranes operate as gaskets. Selecting the wrong type can result in short circuits, water ingress, corrosion, or even fire hazards. You must use approved materials, choose the right size box, and make sure you ground everything correctly.
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