MagneticBalance Test

[haisa]

Hello everyone,
We conducted a magnetic balance test on a 30MVA, 132/33KV transformer on all the taps at both primary and secondary. The results showed that the sum of the two voltages are different from the applied voltage by about 6V to 10V. Is this acceptable? What could be wrong please.

 

[collies99]

Is neutrsl ground removed ?

 

[haisa]

Yes it is removed.

 

[dfdt]

I would not bother too much if measured voltages on other two limb do not add upto applied voltage as long as excitation current for each limb is identical

 

[collies99]

We allow +/-5 % on the outside limbs but do expect equality when testing the middle limb.

 

[haisa]

Thanx a lot