Kiểm tra & Khắc phục sự cốCâu 507 / 521
During commissioning you want to confirm that a metal equipment enclosure is effectively bonded. Which check best verifies a low-impedance bond to ground?
a.Measure 120 V from enclosure to a hot conductor
b.Confirm the enclosure is painted for corrosion resistance
c.Verify the enclosure feels cool to the touch
d.Measure a very low resistance/continuity between the enclosure and the grounding-electrode/EGC point
Giải thích
A low-resistance continuity reading between the enclosure and the grounding system confirms an effective bond that can carry fault current. Reading 120 V to a hot (a) is a shock hazard test, not a bond check; paint (b) actually impairs bonding at contact surfaces; and temperature (c) tells nothing about the ground path.
Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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