Assumed the transformer vector group is DYn11;
1.1U1V1W-which is primary -Delta Connection
2.2U2V2W- Which is secondary-Star connection
3.join 1U& 2U terminals
4.Supply 1U-1V-1W 440v Measured
a.1U-1V
b.1V-1w
c.1W-1U
d.1W-2W
e.1V-2W
f.1V-2V
g.1W-2V
h.1U-2N
i.1V-2N
TO CHECK
1.1V-2W=1V-2V
2.1W-2V>1W-2W
3.1U-1V=1V-2N+1U-2N
From above check(1,2,3) the vector group of transformer is
verified

Assumed the transformer vector group is DYn11;
1.1U1V1W-which is primary -Delta Connection
2.2U2V2W2N- Which is secondary-Star connection
3.By connecting terminals 1U& 2U
4.Then three phase Supply is given to 1U-1V-1W
5.By measuring the terminal given below
We get
a.1U-1V
b.1V-1w
c.1W-1U
d.1W-2W
e.1V-2W
f.1V-2V
g.1W-2V
h.1U-2N
i.1V-2N
THE BELOW GIVEN CONDITION IS SATISFIED THEN DYn11 IS
CONFIRMED
1.1V-2W=1V-2V
2.1W-2V>1W-2W
3.1U-1V=1V-2N+1U-2N

Vector group is punched on the name plate based on the user
requirement by the manufacture. Aim of vector group test is
at site is to check if their is any damage in the windings
during transportation and erection.
3 -phase AC supply is given on HV side. R-Phase HV and r-
phase LV shorted for all vector group of transformer

Then to qualify the test following conditions are to be
satisfied after measurement of voltages.

Procedure given by Mr. dinesh kumar & Mr. E.saravanan is
correct but is there any explanation for this three
conditions.
1.1V-2W=1V-2V
2.1W-2V>1W-2W
3.1U-1V=1V-2N+1U-2N

can anybody tell hw u r writing this is the vector group
calculation for this one.....
what happens if the voltages r not satisfied for the
specified vector group and if so what to do.......

1.1U1V1W-which is primary -Delta Connection
2.2U2V2W- Which is secondary-Star connection
3.join 1U& 2U terminals
4.Supply 1U-1V-1W 440v Measured
a.1U-1V
b.1V-1w
c.1W-1U
d.1W-2W
e.1V-2W
f.1V-2V
g.1W-2V
h.1U-2N
i.1V-2N
TO CHECK
1.1V-2W=1V-2V
2.1W-2V>1W-2W
3.1U-1V=1V-2N+1U-2N
From above check(1,2) the vector group of transformer is
verified

21. What is the purpose of taking Capacitance and Tan Delta
Test in
Transformer bushing?
22. What are the protections to be used for Generator?
23. Draw the vector diagram and condition for the
following: 1) Dyn1
2) Ynd0 3) YnYn0
24. What happens when the polarity changes in CT? Explain
briefly?
25. Explain the Term in CT Name Plate – Class: 5P10