Journeyman Electrician Exam (NEC)Wiring Methods and MaterialsEasy

A maintenance technician is replacing a flexible cord on a portable 277-volt industrial machine. The machine requires a grounding conductor. According to NEC 400.22(B), what is the color that must be used for the grounding conductor in a flexible cord?

  1. ARed
  2. BWhite or Gray
  3. CBlack
  4. DGreen or Green with Yellow Stripes
Show answer & explanation

Correct answer: D. Green or Green with Yellow Stripes

NEC Section 400.22(B) explicitly states that the grounding conductor in a flexible cord shall be identified by a continuous outer finish of green or green with one or more yellow stripes.

Why the other options are wrong

  • A. This color is typically used for ungrounded (hot) conductors.
  • B. These colors are for grounded (neutral) conductors.
  • C. This color is typically used for ungrounded (hot) conductors.

Flexible Cord Grounding Color

The standardized color identification for the equipment grounding conductor within a flexible cord.

  • Ensures proper identification of the grounding path.
  • Critical for safety and preventing electrical shock.
  • Consistent across flexible cords.

Memory trick: Green means ground, safe and sound.

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