CI Test 4- problem 5

[Messi]

what would be the advantage if you were to reconnect a conventional voltage transformer as an autotransformer ? 

The answer is - it could handle more power

one more option is “fewer windings are necessary “ which also seems to be correct to me. 

Can someone explain this ? 

 

[Sthabik PE]

what would be the advantage if you were to reconnect a conventional voltage transformer as an autotransformer ? 

The answer is - it could handle more power

one more option is “fewer windings are necessary “ which also seems to be correct to me. 

Can someone explain this ? 

Let say a conventional transformer is  rated 10kVA. If we use this same 10kVA transformer  and connect it to auto transformer connection, its rating can goes max. say 60 kVA (depends on connection). Hence it can handle more power.

But if you are comparing 10 kVA conventional transformer with another 10 kVA auto transformer, then for same kVA rating, auto transformer will require less wingdings or less copper.

Hope it makes clear to you.

 

[Messi]

Let say a conventional transformer is  rated 10kVA. If we use this same 10kVA transformer  and connect it to auto transformer connection, its rating can goes max. say 60 kVA (depends on connection). Hence it can handle more power.

But if you are comparing 10 kVA conventional transformer with another 10 kVA auto transformer, then for same kVA rating, auto transformer will require less wingdings or less copper.

Hope it makes clear to you.

I agree with you totally. that's what I thought but the Answer in the book is just the first one & not the second. I believe both are correct & this is a typo in the book maybe.

 

[Sthabik PE]

I agree with you totally. that's what I thought but the Answer in the book is just the first one & not the second. I believe both are correct & this is a typo in the book maybe.

"what would be the advantage if you were to reconnect a conventional voltage transformer as an autotransformer ? "

As you can see the question is mentioning to reconnect the same transformer as auto-transformer. If you reconnect the same transformer there is no logic to get less wingdings.

So the answer is only first one not the second.

I don't see typo here.

 

[Messi]

"what would be the advantage if you were to reconnect a conventional voltage transformer as an autotransformer ? "

As you can see the question is mentioning to reconnect the same transformer as auto-transformer. If you reconnect the same transformer there is no logic to get less wingdings.

So the answer is only first one not the second.

I don't see typo here.

Makes sense. I believe I need couple of days off from studying
Appreciate your response