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NEC 300.3(B) Conductors of the Same Circuit Explained

jar546

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Think of a circuit in a building like a team of players in a game. Just like how a team sticks together to play effectively, all the wires (conductors) of a single circuit need to be grouped together. This includes not just the main wires carrying the current but also the grounding wires that are there for safety.

Why do this? It's a bit like preventing players from getting too hot and tired in a game. Grouping these wires together in the same path – be it a pipe (raceway), a wire tray, or a cable – helps avoid something called 'inductive heating.' This is a fancy way of saying the wires don't get unnecessarily hot due to electrical interference between them.

Also, keeping them together helps the circuit work efficiently, like a well-coordinated team, by not letting the overall electrical resistance (impedance) increase. If the wires were scattered, the circuit wouldn't work as smoothly.

There are some exceptions to this rule, but they're specific cases. For underground setups, there's a similar guideline to follow, ensuring everything stays safe and efficient down there too.

So, in short, keeping all the wires of a circuit together is about safety, efficiency, and preventing unwanted heat. It’s like keeping a team in formation to win the game!
 
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