TN LLE Grounding and Bonding 2

Question 1

Per NEC 250.122, what is the minimum size equipment grounding conductor for a circuit protected by a 60-ampere overcurrent device?

Accepted Answer

10 AWG

Answer

14 AWG

Answer

12 AWG

Answer

8 AWG

Question 2

What is the purpose of the main bonding jumper in a service panel?

Accepted Answer

To bond the grounded conductor (neutral) to the equipment grounding conductor and enclosure at the service

Answer

To connect the neutral bus to the panel enclosure

Answer

To connect the panel to the water pipe

Answer

To provide a path for normal current return

Question 3

Per NEC 250.64(A), what protection is required for aluminum or copper-clad aluminum grounding electrode conductors?

Accepted Answer

They must not be installed where subject to physical damage or corrosive conditions, and must not be in contact with masonry or earth

Answer

No special protection required

Answer

They must be in conduit at all times

Answer

They require a special coating

Question 4

What is an intersystem bonding termination per NEC 250.94?

Accepted Answer

An accessible device for bonding communications systems (cable, telephone, satellite) to the building grounding electrode system

Answer

A connection between two electrical services

Answer

A splice between ground rods

Answer

A connection between the water pipe and gas pipe

Question 5

Per NEC 250.104(A), what building systems must be bonded to the electrical grounding system?

Accepted Answer

Metal water piping, metal gas piping, and other metal piping systems that may become energized

Answer

Only the cold water pipe

Answer

Only systems containing electrical conductors

Answer

Only systems within 5 feet of electrical equipment

Question 6

When are supplemental ground rods required in addition to a single ground rod per NEC 250.53(A)(2)?

Accepted Answer

When the single rod does not achieve 25 ohms or less to ground

Answer

Always — a single rod is never sufficient

Answer

Only in commercial installations

Answer

Only when the soil is sandy