ABB REG670 Applications Manual page 97

1MRK 502 071-UEN -
Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
Application manual
In case of a solid earth fault in high impedance earthed or unearthed systems the
primary value of Uo voltage will be equal to:
U
-
Ph Ph
= =
U 0 U
-
Ph E
3
EQUATION1931 V2 EN
Figure 30 gives an overview of required actions by the user in order to make this
measurement available to the built-in protection and control functions within the IED.
Protected Object
L1 L2 L3
R
6.6 kV
3
IEC06000603 V4 EN
Figure 30: Neutral point connected VT
IED
2
1
Uo
100 V
Section 4
Analog inputs
(Equation 11)
5
3
SMAI2
BLOCK AI3P
REVROT AI1
# Not Used ^GRP2L1 AI2
# Not Used ^GRP2L2 AI3
^GRP2L3 AI4
# Not Used
^GRP2N AIN
4
IEC06000603-4-en.vsdx
91