Dịch vụ & Phân phốiCâu 14 / 521
Where two rod electrodes are used to meet the supplemental-electrode rule, what is the minimum spacing between them?
a.6 ft (1.8 m)
b.3 ft (0.9 m)
c.10 ft (3.0 m)
d.4 ft (1.2 m)
Giải thích
Per 250.53(A)(3), where multiple rod, pipe, or plate electrodes are used, they must be at least 6 ft (1.8 m) apart. Closer spacings reduce the benefit of the second electrode and do not satisfy the code.
Trích dẫn luật: 2023 NEC §250.53(A)(3)Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- Ungrounded conductors are increased in size for voltage drop. What must happen to the equipment grounding conductor?
- What is the general rule for the metal water piping system inside a building served by an electrical service?
- What is the function of the main bonding jumper at a service?
- Using the 75 C column of Table 310.16, what is the allowable ampacity of a 3/0 AWG copper conductor?
- What is the 75 C ampacity of a 4/0 AWG copper conductor per Table 310.16?
- At the 75 C column of Table 310.16, what is the ampacity of a 1/0 AWG copper conductor?
Cập nhật gần nhất: · quy trình kiểm tra
Đội Ngũ Biên Tập PrepPass · Đối chiếu với California CSLB C-10 Electrical Trade Examination · Quy trình kiểm tra