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

NEC Table 250.122 requires a minimum 10 AWG copper equipment grounding conductor for a 60-ampere rated overcurrent device.

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

The main bonding jumper connects the grounded conductor (neutral), equipment grounding conductors, and the service enclosure together, creating the effective ground-fault current path.

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

NEC 250.64(A) prohibits aluminum or copper-clad aluminum GECs from being used where in direct contact with masonry, earth, or where subject to corrosive conditions.

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

NEC 250.94 requires an intersystem bonding termination at the service or disconnect that provides accessible terminals for bonding communications systems to the grounding electrode system.

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

NEC 250.104(A) requires bonding of interior metal water piping, and 250.104(B) requires bonding of other metal piping systems including gas piping that may become energized.

TN LLE - Tennessee Limited Licensed Electrician Practice Test

TN LLE - Tennessee Limited Licensed Electrician Practice Test

TN LLE Grounding and Bonding 2