Question
In the United States, what circuit does black wire insulation indicate in a three-wire 120 V cable?
Answer Options
- A) Neutral
- B) Hot
- C) Equipment ground
- D) Black insulation is never used
Correct Answer: B
Explanation
In standard US AC wiring for 120V circuits, different colors are used to identify the function of each wire for safety and compliance. The black wire (or sometimes red) is always the Hot wire, meaning it is the conductor carrying the high electrical potential relative to the earth. It is the wire that, if touched, will cause a shock.
For reference, the white wire is the Neutral (return path) and the bare copper or green wire is the Equipment Ground (safety path). Knowing these standard color codes is crucial when working on power wiring to avoid shock or fire hazards.
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