NEC Grounding and Bonding 2

Question 1

What is the minimum size copper grounding electrode conductor required for a 200-ampere service with a single ground rod electrode per NEC Article 250?

Accepted Answer

6 AWG copper

Answer

NEC 250.66 limits the grounding electrode conductor to a single rod, pipe, or plate electrode to 6 AWG copper regardless of service size.

Question 2

According to NEC 250.53, when a single ground rod does not achieve 25 ohms or less to earth, what must be done?

Accepted Answer

Install one additional electrode

Answer

NEC 250.53(A)(2) requires one additional electrode when resistance of a single rod exceeds 25 ohms.

Question 3

Which NEC article specifically covers grounding and bonding requirements?

Accepted Answer

Article 250

Answer

NEC Article 250 exclusively covers all grounding and bonding requirements for electrical systems.

Question 4

What is the purpose of an equipment bonding jumper (EBJ) per NEC 250.102?

Accepted Answer

Connect metal parts to ensure electrical continuity

Answer

An EBJ connects metal enclosures, raceways, or equipment to ensure a low-impedance fault current path.

Question 5

Per NEC 250.24(A), where must the grounding electrode conductor connection be made on a service entrance?

Accepted Answer

At the service entrance equipment

Answer

NEC 250.24(A) requires the grounding electrode conductor to be connected to the service entrance equipment.

NEC Practice Test

NEC Practice Test

NEC Grounding and Bonding 2