ABB RELION RET670 Applications Manual page 367

1MRK 504 163-UUS A
Transformer protection RET670 2.2 ANSI
Application manual
Phase-to-ground fault in forward direction
With reference to figure 170, the following equations for the setting calculations can be
obtained.
Index PHS in images and equations reference settings for Phase
selection with load encroachment function FDPSPDIS (21) and index
Zm reference settings for Distance protection function (ZMQPDIS, 21).
Section 8
Impedance protection
M13142-6 v7
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