Megger AVTMTTR100 - Page 58

M
AVTMTTR100-ENG Rev 6 Nov 2015
50
Table 5-4. Transformer Winding Phase Relationship (Australian Std. 2374, Part 4 - 2003)
Copyright 2009 Megger
Winding Connection Winding Tested
Diag
No.
IEC
Vector
Group
High-Voltage
Winding (HV)
Low-Voltage
Winding (LV)
Phase
Tested
Winding
Shorted
By TTR
High-
Voltage
Winding
Low-
Voltage
Winding
Measured
Turn
Ratio
Remarks
20
Yy6
A+B
B+C
C+A
A2 - B2
B2 - C2
C2 - A2
b1 - a1
c1 - b1
a1 - c1
HV
LV
No neutral
accessible
on HV & LV
windings
21
Yzn1
A+B
B+C
C+A
A2 - B2
B2 - C2
C2 - A2
n - b4
n - c4
n - a4
HV
LV
• 3
With or
without
neutral
accessible
on wye
winding
22
Yz1
A+C+A+B
B+A+C+B
C+B+C+A
B
2
- C
2
C
2
- A
2
A
2
- B
2
A
2
- (B
2
+C
2
)
B
2
- (C
2
+A
2
)
C
2
- (A
2
+B
2
)
a
4
- b
4
b
4
- c
4
c
4
- a
4
HV
LV
•
3
2
No neutral
accessible
on HV & LV
windings
23
Yzn11
A+B
B+C
C+A
A2 - B2
B2 - C2
C2 - A2
a4 - n
b4 - n
c4 - n
HV
LV
• 3
With or
without
neutral
accessible
on wye
winding
24
Yz11
A
B
C
B
2
- C
2
C
2
- A
2
A
2
- B
2
A
2
- (B
2
+C
2
)
B
2
- (C
2
+A
2
)
C
2
- (A
2
+B
2
)
a
4
- c
4
b
4
- a
4
c
4
- b
4
HV
LV
•
3
2
No neutral
accessible
on HV & LV
windings
25
YNd1
A
B
C
A2 - N
B2 - N
C2 - N
a2 - b2
b2 - c2
c2 - a2
HV
LV • 3
Neutral
accessible
on wye
winding