EETC Power Distribution 2

Question 1

What is the primary purpose of a distribution transformer's tap changer?

Accepted Answer

To adjust the output voltage to compensate for load variations

Answer

Tap changers adjust the transformer turns ratio to maintain proper secondary voltage as load and primary voltage fluctuate.

Question 2

In a radial distribution system, what is the main disadvantage compared to a loop or network system?

Accepted Answer

Loss of service to all customers downstream of a fault

Answer

In a radial system, a single fault interrupts power to all customers downstream of the fault point since there is only one supply path.

Question 3

Which conductor arrangement is used in most North American overhead distribution systems serving residential areas?

Accepted Answer

Wye four-wire multigrounded neutral

Answer

The multigrounded wye four-wire system is standard in North America because it provides both single-phase 120/240V service and neutral grounding at multiple points.

Question 4

A capacitor bank installed on a distribution feeder primarily improves which system parameter?

Accepted Answer

Power factor and reduces reactive power demand

Answer

Shunt capacitor banks supply reactive power locally, improving power factor, reducing current draw, and decreasing line losses.

Question 5

What does the term 'feeder' refer to in power distribution?

Accepted Answer

The medium-voltage circuit leaving a substation to serve distribution loads

Answer

A distribution feeder is the medium-voltage (typically 4–35 kV) circuit that originates at a substation and carries power to distribution transformers serving customers.

(EETC) Electrical Technician Certification Practice Test

(EETC) Electrical Technician Certification Practice Test

EETC Power Distribution 2