ETO Power Generation & Distribution 3

Question 1

According to classification society rules, what is the maximum allowable voltage drop for main lighting circuits on ships?

Accepted Answer

2.5%

Answer

6%

Answer

10%

Answer

15%

Question 2

Which source provides emergency electrical power to essential services if all main generators fail on a ship?

Accepted Answer

Emergency generator

Answer

UPS system covering all loads

Answer

Shore power connection

Answer

Transitional battery bank only

Question 3

According to SOLAS requirements, what is the minimum duration for which an emergency generator on a cargo ship must be capable of supplying power?

Accepted Answer

18 hours

Answer

3 hours

Answer

36 hours

Answer

12 hours

Question 4

What is the primary purpose of performing an insulation resistance test on a ship's electrical equipment?

Accepted Answer

To detect deterioration of electrical insulation that may lead to earth faults or electric shock hazards

Answer

To measure conductor resistance under full load conditions

Answer

To verify correct phase sequence of the power supply

Answer

To test the tripping characteristics of circuit breakers

Question 5

Why do ships typically use an IT (Insulated Neutral) earthing system rather than a solidly earthed neutral system?

Accepted Answer

To allow continued operation during a single earth fault while crew locates and repairs it

Answer

To provide lower earth fault current for quicker fuse operation

Answer

To comply with IEC 60364 standards for all electrical installations

Answer

To eliminate the need for earth fault monitoring relays

Question 6

What alarm condition is activated on a ship's main switchboard when insulation resistance drops below the minimum acceptable threshold?

Accepted Answer

Earth fault alarm

Answer

Overcurrent alarm

Answer

Under-voltage alarm

Answer

Reverse power alarm

Question 7

What is the minimum insulation resistance value typically required for low-voltage electrical equipment on ships according to classification society standards?

Accepted Answer

1 MΩ

Answer

0.1 MΩ

Answer

10 MΩ

Answer

100 kΩ