Services & DistributionQuestion 14 of 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)
Explanation
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.
Law Reference: 2023 NEC §250.53(A)(3)Practice all 521 questions free — no signup required.
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