CPC 100 V 3.20
Transformer - 2
Transformer
The Settings page of the TRRatio test card offers an offline Auto-tap fill function. It
automatically fills in the nominal ratio table of the TRRatio test card for symmetric tap changers.
The total number of taps minus the middle positions defines the number of taps above and
below the middle position(s). To determine the voltage for each tap position, the nominal ratio
of the middle position(s) and the deviation percentage are needed and the HV tap changer
check box needs to be activated if applicable.
The following table shows the V prim and Vsec settings on the TRRatio test card for different
transformer’s winding connections.
Note: The table is valid for manual wiring and in connection with the CP SB1.
In the Transformer high-voltage side column, + means that the terminals in the CP SB1 are
short circuited.
IEC
60076
vector
group
Winding connection Mea-
sure-
ment
Transformer
high-voltage side
Transformer
low-voltage side
Mea-
sured
turn ratio
HV / H LV /X
Dd0 A U-V / H1-H2 u-v / X1-X2 1
B V-W / H2-H3 v-w / X2-X3
C W-U / H3-H1 w-u / X3-X1
Yy0 A U-V / H1-H2 u-v / X1-X2 1
B V-W / H2-H3 v-w / X2-X3
C W-U / H3-H1 w-u / X3-X1
Dz0 A U-V / H1-H2 u-v / X1-X2 1
B V-W / H2-H3 v-w / X2-X3
C W-U / H3-H1 w-u / X3-X1