EETC Grounding Systems 2

Question 1

What is the minimum burial depth for a ground ring conductor installed in soil under the NEC?

Accepted Answer

18 inches

Answer

NEC 250.52(A)(4) requires a ground ring to be buried at least 30 inches (762 mm) below the surface of the earth — but the conductor within that ring must be at least 2 AWG and buried no less than 2.5 feet; the 30-inch rule applies.

Question 2

Which NEC article primarily governs grounding and bonding requirements?

Accepted Answer

Article 250

Answer

NEC Article 250 covers all requirements for grounding and bonding of electrical systems and equipment.

Question 3

A separately derived system's grounding electrode conductor must be connected at which point?

Accepted Answer

At the source of the separately derived system

Answer

Per NEC 250.30, the grounding electrode conductor for a separately derived system must connect at the source — such as the secondary of a transformer.

Question 4

What term describes the low-impedance path provided to facilitate the operation of overcurrent devices during a ground fault?

Accepted Answer

Effective ground-fault current path

Answer

An effective ground-fault current path is a permanent, low-impedance electrically conductive path that facilitates overcurrent device operation during a ground fault.

Question 5

When is a main bonding jumper required?

Accepted Answer

At the service entrance to bond the neutral to the equipment ground

Answer

The main bonding jumper connects the grounded conductor (neutral) to the equipment grounding conductor and service equipment enclosure at the service entrance.

(EETC) Electrical Technician Certification Practice Test

(EETC) Electrical Technician Certification Practice Test

EETC Grounding Systems 2