IEC Grounding and Bonding 4

Question 1

Which of the following is NOT listed as a grounding electrode in NEC 250.52(A)?

Accepted Answer

Metal underground fuel (gas) piping

Answer

Metal underground fuel (gas) piping is explicitly prohibited from use as a grounding electrode per NEC 250.52(B), whereas the others are permitted electrodes.

Question 2

What is the minimum size copper conductor for a ground ring used as a grounding electrode per NEC 250.52(A)(4)?

Accepted Answer

#2 AWG

Answer

NEC 250.52(A)(4) requires the ground ring to consist of at least #2 AWG copper conductor encircling the building buried at least 2.5 feet deep.

Question 3

When installing a concrete-encased grounding electrode (Ufer ground), the conductor or rebar must be encased in at least how many inches of concrete?

Accepted Answer

2 inches

Answer

NEC 250.52(A)(3) requires the conductor or rebar to be encased in at least 2 inches of concrete at the bottom of a foundation or footing.

Question 4

Per NEC 250.119, equipment grounding conductors must be identified by which color(s)?

Accepted Answer

Green, green with yellow stripes, or bare

Answer

NEC 250.119 requires insulated equipment grounding conductors to be identified by the color green or green with one or more yellow stripes, or they may be bare.

Question 5

A bonding jumper installed on the load side of the service to connect multiple equipment grounding conductors is called a(n):

Accepted Answer

Equipment bonding jumper

Answer

An equipment bonding jumper is used on the load side of the service to ensure electrical continuity between multiple equipment grounding conductors or enclosures.

IEC - Independent Electrical Contractors Practice Test

IEC - Independent Electrical Contractors Practice Test

IEC Grounding and Bonding 4