Problem with a current transformer

[cocopa]

Hello! I have a current sense transformer with 50 turns ratio and i want to amplify a sine wave from 1v to 50v and then convert it to dc, however the transformer doesn't seem to produce the desired output.
I checked the specifications of the transformer and i don't exceed them,I'm within range, so I have 2 questions:
i)Is a CT transformer (in general) suitable for this kind of job?
ii)How do i test the transformer to see if it's working? Do i just put an ac voltage on the primary and measure the output voltage on the secondary?
Thank you.

 

[KerimF]

As you know, the primary coil of a current transformer is driven by current not voltage. I mean the primary voltage should be, as it is supposed to be, relatively very small so that the circuit won't be affected too much by inserting the transformer to monitor a current.

 

[cocopa]

Thank you for your reply KerimF. I don't want to monitor current, i just want to boost up my signal,that means that a CT transformer is not suitable for my application?
Then, if a CT transformer with 50 turns ratio won't amplify 50 times my input voltage what is its effect on it?

 

[FvM]

If you see the CT just as ideal transformer, there would be no difference between voltage or current transformer.

But due to it's low winding count, usually a single primary turn, a real current transformer has a low parallel inductance and also a rather low saturation voltage. This means you have to drive considerably current to achieve 1 V primary and it will possibly saturate at lower voltage.

 

[chuckey]

The basic concept of a current transformer is to measure large currents. So a typical current transformer will be like a doughnut (toroid) where the large current carrying conductor passes through the centre and the toroid core is wound with 500 turns of wire, such a transformer would be designed so that 1000A flowing through the centre conductor would induce a 5A current through its winding, which in turn would then be measured by a 5A AC ammeter which would drop 100 mV across its terminals at the full 5A, calibrated to read 0-1000Amps.
So note, a current transformer MUST be loaded with a low resistance and is rated at a low voltage out. So the above transformer, if it was used to feed a high impedance digital circuit, must have a resistor of 2 mOhms or at least very low , perhaps 1 ohm. if you did not have this low value load, on switch on, the voltage coming out of the transformer would be very high and could damage amplifier circuit.
If you have designed the transformer your self, you have to think about the secondary impedance being reflected back into the primary circuit which would add series inductance and resistance to it (which might upset it).
Frank

 

[szhighstar]

you should be consider precision question, including ratio error and shift error

 

[kam1787]

What is the frequency?
How are you measuring - with what device?

Maybe a diagram of the circuit would help.