What will happen if I connect current transformer in reverse direction, means instead of applying current in primary if I apply some mA of current in secondary(less than the rated secondary current) then what will be the current in primary (assume that in primary I have kept a thick wire with ammeter in series).
I tried this experiment with TT-50SD. I applied 5mA,60Hz current to secondary of this CT and found that current in primary wire was only 1.444mA and increasing secondary current further was not increasing this primary current. Which means core was saturated, is there a formula which will give this saturated primary current value and is it harmful for CT to do this kind of experiment.
Best Answer
In principle it would work -- you would get a current in the (original) primary greater than the forced current by a factor equal to the number of secondary turns.
However, the voltage driving this primary loop is very low, and so you would really need low resistance wire in that loop. The resistance of an ammeter would dominate the result and not be representative. If you could use a Hall sensor, or other lossless/low resistance current sensor (another current transformer !), it would work reasonably well.