Dịch vụ & Phân phốiCâu 113 / 521
When installing a surge-protective device (SPD), the best practice for the connecting conductors is to:
a.Make them as long as possible for flexibility
b.Coil extra length behind the panel
c.Keep them as short and straight as practicable
d.Route them alongside the grounding electrode conductor for the full length
Giải thích
SPD performance depends on low conductor impedance, so the leads should be kept as short and straight as practicable to minimize added voltage from lead inductance during a surge. Long or coiled leads raise the let-through voltage and reduce protection, defeating the purpose of the device.
Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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