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B TD
i
C
ipickup
=
+
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EQUATION1722 V1 EN-US
(Equation 185)
Further description can be found in the technical reference manual.
tPRCrvx, tTRCrvx, tCRCrvx
: Parameters for user programmable of inverse reset time
characteristic curve. Further description can be found in the technical reference
manual.
9.4.3.6
Transformer application example
SEMOD55591-4 v8
Two main cases are of interest when residual overcurrent protection is used for a power
transformer, namely if residual current can be fed from the protected transformer
winding or not.
The protected winding will feed ground-fault (residual) current to ground faults in the
connected power system. The residual current fed from the transformer at external
phase-to-ground faults is highly dependent on the total positive and zero-sequence
source impedances. It is also dependent on the residual current distribution between the
network zero-sequence impedance and the transformer zero-sequence impedance. An
example of this application is shown in Figure
Section 9
1MRK 502 071-UUS A
Current protection
372
Generator protection REG670 2.2 ANSI and Injection equipment REX060, REX061, REX062
Application manual
Summary of Contents for RELION 670 SERIES REG670
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