Question 87Electricity & Electronics - 1st Asst/Chief

70% to pass

Propulsion AC generators creating 4160 VAC use transformers to provide nominally 120 VAC to the automatic voltage regulator. What is the turn’s ratio of this step-down transformer?

A1:4
B4:1
C35:1
D40:1
AI Explanation

The correct answer is C) 35:1. The transformer used to step down the 4160 VAC from the generators to the 120 VAC for the automatic voltage regulator would have a turns ratio of 35:1. This is because the voltage needs to be reduced by a factor of approximately 35 to go from 4160 VAC to 120 VAC. The other options are incorrect because: A) 1:4 would step up the voltage, not step it down. B) 4:1 would not provide the necessary 35:1 step-down ratio. D) 40:1 is close but not exactly the correct turns ratio.

Want to practice with timed exams?

Download Coast Guard Exams for the full exam experience.

Get the App