Which statement completes the following: service heads shall have conductors of different potential brought out through separately ___ openings?

Which statement completes the following: service heads shall have conductors of different potential brought out through separately ___ openings?

• A. bushed
• B. sized
• C. isolated
• D. grounded

Answer: (A)

The principle being tested is insulating separation of conductors with different potentials by using separate insulated paths. In a service head, conductors of different potential must exit through individually insulated openings, provided with bushings. These bushings act as insulating sleeves that line each opening, keeping the conductors from contacting the metal enclosure or each other and preventing arcing or insulation damage. That’s why the phrase is “bushed openings.” Other terms don’t convey this insulation and separation role—merely sizing an opening doesn’t ensure insulation, “isolated” openings isn’t the standard term for this requirement, and “grounded” openings would misapply grounding to the opening itself, which isn’t the purpose here.

The principle being tested is insulating separation of conductors with different potentials by using separate insulated paths. In a service head, conductors of different potential must exit through individually insulated openings, provided with bushings. These bushings act as insulating sleeves that line each opening, keeping the conductors from contacting the metal enclosure or each other and preventing arcing or insulation damage. That’s why the phrase is “bushed openings.” Other terms don’t convey this insulation and separation role—merely sizing an opening doesn’t ensure insulation, “isolated” openings isn’t the standard term for this requirement, and “grounded” openings would misapply grounding to the opening itself, which isn’t the purpose here.