ETO Power Generation & Distribution

Question 1

What is the typical operating voltage for main power distribution on large commercial vessels?

Accepted Answer

440V AC

Answer

120V AC

Answer

240V AC

Answer

690V AC

Question 2

What type of alternator is most commonly used in a ship's power generation system?

Accepted Answer

Salient pole synchronous generator

Answer

Squirrel cage induction generator

Answer

Wound rotor induction generator

Answer

Permanent magnet alternator

Question 3

What is the primary purpose of a bus tie breaker in a ship's electrical distribution system?

Accepted Answer

To connect two separate busbars enabling parallel generator operation

Answer

To protect individual circuits from overcurrent faults

Answer

To regulate voltage levels on the main switchboard

Answer

To isolate the shore power connection from the vessel

Question 4

Which protection relay prevents a generator from absorbing power from the busbar when operating in parallel?

Accepted Answer

Reverse power relay

Answer

Overcurrent relay

Answer

Earth fault relay

Answer

Under-voltage relay

Question 5

What is the standard frequency used for electrical power generation on US-flagged commercial vessels?

Accepted Answer

60 Hz

Answer

50 Hz

Answer

400 Hz

Answer

25 Hz

Question 6

What device automatically maintains constant terminal voltage of a synchronous generator as electrical load varies?

Accepted Answer

Automatic Voltage Regulator (AVR)

Answer

Governor

Answer

Power factor controller

Answer

Synchroscope

Question 7

What is the primary function of the governor on a diesel generator set aboard a ship?

Accepted Answer

To maintain constant engine speed regardless of load changes

Answer

To regulate the output voltage of the alternator

Answer

To protect the generator from overcurrent faults

Answer

To synchronize generators before paralleling