Services & DistributionQuestion 53 of 110
A single made electrode (ground rod) must be supplemented unless its resistance to earth does not exceed what value?
a.25 ohms
b.5 ohms
c.10 ohms
d.1 ohm
Explanation
A single rod, pipe, or plate electrode must be supplemented by a second electrode unless it has a resistance to earth of 25 ohms or less.
Law Reference: 2023 NEC 250.53(A)Practice all 110 questions free — no signup required.
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