transformer question

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That would depend on what you put into it as to what you get out of it.
 
I don?t know of anything that is measured in terms of ?volts per turn.? But my calculator tells me that 1.25 times 192 is 240.

Where did this question come from?
 
Volts per turn is a metric often used in the design of transformers (and motors).

It is simply a way of describing the rate change of flux carried by the transformer core, by the voltage that would be induced in a _single_ coil wrapped around that core.

Turns electrically in series add voltage, so if you have 192 turns with 1.25V induced per turn, then you get 240V. Of course, you might have something like a center tapped 192 turn coil, providing 120/240V, or some other design feature that we've not been told about.

-Jon
 
Test Question

Test Question

This is a question that was presented on a Journeyman's exam this week. The question never mention the primary or the secondary, It simply said that a transformer has 1.25 volts per turn. There are 192 turns. So the first thing someone would do is multiply 1.25 times 192 and the answer is 240 volts. Well there it is right next to the letter C. So you circle it and move on. Well after finishing the test you start your review and this question pops up again. That answer is to straight forward for a test. A transformer has a ratio. Most are 2:1. So if the primary is 240 volts and the ratio is 2:1 the answer would be 120 volts. 120 volts happened to be answer B. The trouble is that with such limited information you will never be able to agree on the correct answer. There is no way to ask the state for the answer unless you fail the test and sit for a review. So I quess we will never know. Has anyone else had that same question from the ocean state.
Thanks,
Fran
 
This imaginary transformer could also be a 1:1 isolation transformer, so we have to go with the only known parameter. Thus the correct answer, without any speculation, must be (1.25 * 192) 240.
 
Exactly, It does not mater if it's 2000:1 ratio, they are talking about 1.25V and 192 turns on the same coil. So it's 240V
Gosh, I thought I just replied to this question?
 
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