Question 87Electricity/Electronics - 1st Asst/Chief70% 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?
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.
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