Journeyman Electrician’s Exam Journeyman Electrician's Grounding and Bonding 4

Question 1

When two ground rods are used as a supplemental electrode system, what is the minimum spacing between them per NEC 250.53(B)?

Accepted Answer

6 feet

Answer

Per NEC 250.53(B), rod and pipe electrodes must be spaced at least 6 feet apart to avoid overlapping effective ground areas.

Question 2

A concrete-encased grounding electrode (Ufer ground) must have at least how many feet of bare or zinc-coated steel reinforcing bars?

Accepted Answer

20 feet

Answer

Per NEC 250.52(A)(3), the concrete-encased electrode requires at least 20 feet of one or more bare steel reinforcing bars in direct contact with earth.

Question 3

Which of the following is the correct term for the low-impedance path intended to carry fault current back to the source?

Accepted Answer

Effective ground-fault current path

Answer

The effective ground-fault current path is the intentional, low-impedance path that carries fault current from the fault point back to the electrical supply source.

Question 4

At a subpanel in a detached garage fed by a feeder from the house, which conductors must be run to the subpanel?

Accepted Answer

Hot, neutral, and a separate equipment grounding conductor

Answer

A feeder to a separate structure must include a separate equipment grounding conductor; the neutral and ground must not be bonded at the subpanel.

Question 5

What is the minimum size conductor required for a ground ring surrounding a building per NEC 250.52(A)(4)?

Accepted Answer

2 AWG bare copper

Answer

Per NEC 250.52(A)(4), a ground ring must consist of at least 2 AWG bare copper conductor encircling the building.

Journeyman Electrician’s Exam Practice Test

Journeyman Electrician’s Exam Practice Test

Journeyman Electrician’s Exam Journeyman Electrician's Grounding and Bonding 4