Core TradesCâu 183 / 700
When a driven ground rod is used as a grounding electrode, what is the MINIMUM length that must be in contact with the soil?
a.4 feet
b.6 feet
c.8 feet
d.10 feet
Giải thích
A ground rod electrode must have at least 8 feet in contact with the soil to reach reliably moist earth and provide a low-resistance connection. 4 and 6 feet are too shallow, and 10 feet exceeds the required minimum length.
Trích dẫn luật: 2025 CA Electrical Code, Article 250 (Grounding Electrodes)Luyện miễn phí toàn bộ 700 câu hỏi — không cần đăng ký.
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