CEA CEA Grounding, Bonding, and Electrical Service Equipment Questions and Answers 2

Question 1

What is the minimum size copper grounding electrode conductor required for a service with a 350 kcmil copper service entrance conductor?

Accepted Answer

#2 AWG

Answer

#6 AWG

Answer

#4 AWG

Answer

#1/0 AWG

Question 2

What is the minimum burial depth for a ground rod electrode per the NEC?

Accepted Answer

8 feet

Answer

6 feet

Answer

10 feet

Answer

12 feet

Question 3

In a separately derived system (such as a transformer secondary), where is the system bonding jumper installed?

Accepted Answer

At the source of the separately derived system

Answer

At the main service panel only

Answer

At the furthest panel from the transformer

Answer

At the first disconnecting means only

Question 4

What is the maximum resistance permitted for a single ground rod electrode before a supplemental electrode is required per the NEC?

Accepted Answer

25 ohms

Answer

5 ohms

Answer

10 ohms

Answer

50 ohms

Question 5

Which conductor is NOT permitted to be used as a grounding electrode conductor?

Accepted Answer

Aluminum in direct contact with masonry or earth

Answer

Bare copper

Answer

Green-insulated copper

Answer

Stranded copper with green insulation

Question 6

What is the purpose of bonding metallic water piping systems in a building?

Accepted Answer

To ensure all metallic piping is at the same electrical potential, preventing shock hazards

Answer

To use the piping as the primary grounding electrode

Answer

To reduce water pressure fluctuations

Answer

To comply with plumbing codes only