ABB RET670 - Page 118

4. Enter the following settings for all three CT input channels used for the LV side CTs
see table 28.
Table 28: CT input channels used for the LV side CTs
Setting parameter Selected value for both solutions
CTprim 800
CTsec 5
CT_WyePoint ToObject
5. Enter the following settings for all three CT input channels used for the HV side
CTs, see table 29.
Table 29: CT input channels used for the HV side CTs
Setting parameter Selected value for both solution 1
(wye connected CT)
Selected value for both solution 2
(delta connected CT)
CTprim 300
300
173
3
=
EQUATION1888 V1 EN (Equation 30)
CTsec 5 5
CT_WyePoint From Object ToObject
To compensate for delta connected CTs, see equation 30.
6. Enter the following values for the general settings of the Transformer differential
protection function, see table
30.
Table 30: General settings of the differential protection function
Setting parameter
Select value for both solution 1
(wye connected CT)
Selected value for both solution 2
(delta connected CT)
RatedVoltageW1 69 kV 69 kV
RatedVoltageW2 12.5 kV 12.5 kV
RatedCurrentW1 175 A 175 A
RatedCurrentW2 965 A 965 A
ConnectTypeW1 WYE (Y) WYE (Y)
ConnectTypeW2 delta=d
wye=y
1)
ClockNumberW2 1 [30 deg lag]
0 [0 deg]
1)
ZSCurrSubtrW1 On
Off
2)
ZSCurrSubtrW2 Off Off
Table continues on next page
Section 3 1MRK504116-UUS C
IED application
112
Application manual