ABB RET670 Applications Manual page 121

1MRK504116-UUS C
Application manual
Table 32: General settings of the differential protection
Setting parameter
RatedVoltageW1
Rated VoltageW2
RatedCurrentW1
RatedCurrentW2
ConnectTypeW1
ConnectTypeW2
ClockNumberW2
ZSCurrSubtrW1
ZSCurrSubtrW2
TconfigForW1
TconfigForW2
LocationOLTC1
Other parameters
1)
To compensate for delta connected CTs.
2)
Zero-sequence current is already removed by connecting main CTs in delta.
Wye-wye connected power transformer with load tap changer and tertiary not
loaded delta winding
Single line diagrams for two possible solutions for such type of power transformer with
all relevant application data are given in figure 29. It shall be noted that this example is
applicable for protection of autotransformer with not loaded tertiary delta winding as
well.
selected value for both Solution 1
(wye conected CT)
115 kV
24.9 kV
301 A
1391 A
Delta (D)
wye=y
1 [30 deg lag]
Off
On
No
No
Not Used
Not relevant for this application.
Use default value.
Section 3
IED application
Selected value for both Solution 2
(delta connected CT)
115 kV
24.9 kV
301 A
1391 A
WYE (Y) 1)
wye=y
1)
0 [0 deg]
Off
2)
On
No
No
Not Used
Not relevant for this application.
Use default value.
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