An toànCâu 439 / 521
Live parts operating at 50 volts or more must be guarded against accidental contact by:
a.A warning sign posted nearby
b.Painting the parts a bright red color
c.Approved enclosures, or location in a room/vault accessible only to qualified persons, or suitable elevation
d.Wrapping them in electrical tape
Giải thích
Guarding of live parts is achieved through approved enclosures, access limited to qualified persons, or elevation out of reach. A sign, paint, or tape does not physically prevent accidental contact and is not an acceptable guarding method for exposed energized parts at 50V or more.
Trích dẫn luật: 2023 NEC §110.27Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- The clear working space in front of a panelboard must be at least how wide and how high?
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- An electrical room containing exposed live parts that is accessible only to qualified persons must have:
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- Which statement about the grounded (neutral) and equipment grounding conductors is correct?
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