309A Grounding and Bonding 2

Question 1

What is the purpose of the bonding jumper at a service panel?

Accepted Answer

To connect the neutral bus to the equipment grounding bus

Answer

The main bonding jumper connects the neutral bus to the equipment grounding bus at the service entrance panel, establishing the connection between the grounded conductor and the equipment grounding system.

Question 2

Why must the neutral and ground be bonded at only one point in a distribution system?

Accepted Answer

To prevent objectionable current flow on equipment grounding conductors

Answer

If neutral and ground are bonded at multiple points, normal return current can flow through equipment grounding conductors, metal raceways, and building steel, creating shock hazards and fire risks.

Question 3

What is the purpose of an equipment bonding conductor in a raceway system?

Accepted Answer

To provide a low-impedance path for fault current back to the source

Answer

The equipment bonding conductor provides a low-impedance fault current path from any point of a ground fault back to the source, enabling the overcurrent device to operate quickly and clear the fault.

Question 4

According to the CEC, what is the minimum bonding conductor size for a circuit protected by a 60 A breaker?

Accepted Answer

No. 10 AWG

Answer

CEC Table 16 specifies the minimum bonding conductor size based on the overcurrent device rating. For a 60 A circuit, a No. 10 AWG copper bonding conductor is required.

Question 5

What is an intersystem bonding termination?

Accepted Answer

A device providing connection points for bonding communication system grounds to the power system ground

Answer

An intersystem bonding termination provides accessible connection points near the service entrance for bonding communication systems (telephone, cable TV, satellite) to the power system's grounding electrode system.

Red Seal Electrician 309A Practice Test

Red Seal Electrician 309A Practice Test

309A Grounding and Bonding 2