CEA CEA Grounding, Bonding, and Electrical Service Equipment Questions and Answers 3

Question 1

In a residential service panel, the neutral bar and the equipment grounding bar must be bonded together at which location?

Accepted Answer

Only at the main service panel

Answer

Every sub-panel

Answer

At both the main panel and all sub-panels

Answer

At no location — they must always be kept separate

Question 2

What is the minimum ampere rating for a service entrance conductor supplying a single-family dwelling per NEC 230.79?

Accepted Answer

100 amperes

Answer

60 amperes

Answer

150 amperes

Answer

200 amperes

Question 3

Service entrance conductors must be protected from physical damage. What is the maximum length of service entrance cable permitted to run along the outside of a building before entering it, without additional protection per the NEC?

Accepted Answer

The service drop attachment point to the service entrance; no run limit applies if it follows the roofline/wall

Answer

No limit if it follows the building surface

Answer

Maximum 6 feet from the meter socket

Answer

Maximum 10 feet along the exterior wall

Question 4

What is the purpose of a surge protective device (SPD) installed at the service panel?

Accepted Answer

To limit transient overvoltages from lightning or utility switching from reaching equipment

Answer

To reduce the service voltage to 120V

Answer

To provide backup power during outages

Answer

To filter harmonic distortion from loads

Question 5

When installing service entrance conductors in a raceway, what must be done if the raceway passes through a roof or exterior wall?

Accepted Answer

Seal the raceway opening with an approved fitting or sealant to prevent water entry

Answer

Use only aluminum conductors

Answer

Install a junction box at the roof penetration

Answer

Use only rigid metal conduit through the roof

Question 6

Per the NEC, the service disconnecting means must be located at a readily accessible location. For a dwelling unit, it must be located nearest to the point of entry of the service conductors and must disconnect all:

Accepted Answer

Grounded and ungrounded conductors simultaneously

Answer

Ungrounded (hot) conductors only

Answer

Grounded conductor only

Answer

Equipment grounding conductors only