One Rod or Two? The 25-Ohm Rule That Actually Decides Your 200A Grounding
Service Grounding · NEC Reference The rod count on the print rarely matches what actually gets installed in the ground. Short answer: a 200 amp service needs at least one grounding rod, but code requires a second rod, spaced a minimum of six feet from the first, whenever a single rod tests above 25 ohms of resistance to earth. In practice, most residential and commercial 200A installations end up with two rods, because a lone rod rarely tests low enough on its own to satisfy that threshold. ...
2026-07-09

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