# What’s the difference between current-transformer and voltag

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#### ZengLei

##### Full Member level 1
I found that the CT could make the voltage in secondary higher than primary ,so is the CT can be seen as a voltage-transformer????
What’s the difference between current-transformer and voltage-transformer??????
Thanks~~~~~

#### A.Anand Srinivasan

Re: What’s the difference between current-transformer and vo

i think a current transformer gives a voltage proportional to the current in the primary.. for voltage transformer it gives voltage proportional to voltage in primary...

#### ranganath_d

##### Member level 1
Re: What’s the difference between current-transformer and vo

Transformer is a device where energy neither created nor destroyed. in this way CT is the one which is a step up or step down current while holding same energy at input as well as output. same statement applies to voltage transformer...

#### ZengLei

##### Full Member level 1
So,could i use a CT as a VT?????

#### Kral

Re: What’s the difference between current-transformer and vo

ZengLei,
There is no fundamental difference between the two. Typically a current transformer will have a primary with a small number of turns of large diamter wire, to minimize the voltage drop across the primary. This is because you want to be able to measure current (by inserting the primary in series with the circuit to be measured) without altering the current that existed without the current transformer. The current transformer also typically has a high turns ratio. The load resistance that is reflected back to the primary is equal to the (fixed) load resistance connected to the secondary divided by the square of the turns ratio. The lower the reflected resistance is, the smaller the voltage drop across the primary will be.
Regards,
Kral

### ZengLei

points: 2

#### A.Anand Srinivasan

Re: What’s the difference between current-transformer and vo

ya current transformer can be used as voltage transformer too.... but the main thing is they are optimised for different purposes...

### ZengLei

points: 2

#### ZengLei

##### Full Member level 1
Thanks all~~~~~~

and what's the crucial parameter i must note when i use a CT,THANKS~~~~~