According to the NEC, how many grounding conductors may be connected to a grounding electrode by a single listed clamp or fitting?

According to the NEC, how many grounding conductors may be connected to a grounding electrode by a single listed clamp or fitting?

• A. Two
• B. Three
• C. Four
• D. One

Answer: (D)

The key idea is that a listed clamp or fitting used to attach a grounding electrode conductor to the electrode is designed for a single conductor. The listing specifies how many conductors the device can securely hold. In standard practice, you attach only one grounding conductor to a grounding electrode with that clamp, ensuring a tight, reliable contact and consistent impedance. If more than one conductor must be bonded to the same electrode, you must use a clamp that is explicitly rated for multiple conductors or install separate clamps (one per conductor) compatible with the listing. This is why only one grounding conductor may be connected to a grounding electrode by a single listed clamp or fitting.

The key idea is that a listed clamp or fitting used to attach a grounding electrode conductor to the electrode is designed for a single conductor. The listing specifies how many conductors the device can securely hold. In standard practice, you attach only one grounding conductor to a grounding electrode with that clamp, ensuring a tight, reliable contact and consistent impedance. If more than one conductor must be bonded to the same electrode, you must use a clamp that is explicitly rated for multiple conductors or install separate clamps (one per conductor) compatible with the listing. This is why only one grounding conductor may be connected to a grounding electrode by a single listed clamp or fitting.