PC Grounding and Bonding 2

Question 1

According to NEC Article 250, what is the minimum size copper equipment grounding conductor required for a 100A circuit protected by a 100A breaker?

Accepted Answer

#8 AWG

Answer

#6 AWG

Answer

#4 AWG

Answer

#10 AWG

Question 2

Which of the following locations requires a grounding electrode system to include a ground ring if no other electrode is available?

Accepted Answer

Buildings or structures where no other electrode type exists on-site

Answer

Residential service panels under 200A

Answer

Buildings with concrete-encased electrodes already installed

Answer

Commercial occupancies over 1000 sq ft

Question 3

What is the primary purpose of bonding in an electrical system?

Accepted Answer

To establish electrical continuity between conductive parts to eliminate voltage differences

Answer

To provide a return path for fault current to the source

Answer

To reduce the grounding electrode resistance to earth

Answer

To protect equipment from lightning surges

Question 4

A concrete-encased electrode (Ufer ground) must contain at least how many feet of bare or zinc-galvanized steel reinforcing bars or rods?

Accepted Answer

20 feet

Answer

10 feet

Answer

50 feet

Answer

100 feet

Question 5

When installing a grounding electrode conductor in a metal raceway, what additional requirement applies?

Accepted Answer

The raceway must be bonded to the grounding electrode conductor at both ends

Answer

The raceway must be PVC-coated to prevent corrosion

Answer

The raceway must be at least 1-inch trade size

Answer

The raceway must contain only the grounding conductor, no other wiring

Question 6

Which NEC article specifically addresses grounding and bonding requirements?

Accepted Answer

Article 250

Answer

Article 200

Answer

Article 230

Answer

Article 280

Question 7

In a separately derived system (e.g., a transformer), where must the system bonding jumper be installed?

Accepted Answer

At the source of the separately derived system

Answer

At the first overcurrent device downstream

Answer

At the grounding electrode only

Answer

At the main service entrance