Procedure for conduting vector group test on power
transformers.why it is conducted?
Answer Posted / r. n. aggarwal
It is conducted to ascertain the polarity and phase
displacement.
The polarity of two transformer having the same vector
group must be same.
A further check to confirm that the polarity or phase
displacement ( vector group ) of two transformer is the
same.A single three phase LT supply is fed to the HT side
of Transformers and the same phase of the LT suppy must be
connected to the corresponding HT terminals of
Transformers .Then the voltage is checked on LT terminals
of transformers with multimeter between the same phases and
it should read almost zero.
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