Example 2 - ABB Relion 670 Series Applications Manual

1MRK 505 370-UUS Rev. K
I
p
I
s
Setting of current input:
Set parameter
CT_WyePoint with
Transformer as
reference object.
Correct setting is
"ToObject"
ANSI05000753 V2 EN-US
Figure 14:
Figure 14
shall be done according to the figure. To protect the line, direction of the directional functions of the line
protection shall be set to Forward. This means that the protection is looking towards the line.
4.2.2.2

Example 2

Two IEDs used for protection of two objects and sharing a CT.
Figure 15:
This example is similar to example 1, but here the transformer is feeding just one line and the line
protection uses the same CT as the transformer protection does. The CT direction is set with different
reference objects for the two IEDs though it is the same current from the same CT that is feeding the two
IEDs. With these settings, the directional functions of the line protection shall be set to Forward to look
towards the line.
4.2.2.3 Example 3
One IED used to protect two objects.
Busbar protection REB670
Application manual
Transformer
Transformer
protection
IED
Setting of current input:
Set parameter
CT_WyePoint with
Transformer as
reference object.
Correct setting is
"ToObject"
Example how to set CT_WyePoint parameters in the IED
shows the normal case where the objects have their own CTs. The settings for CT direction
Example how to set CT_WyePoint parameters in the IED
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Line
I
I
p p
I
s
Setting of current input:
Set parameter
CT_WyePoint with
reference object.
Correct setting is
"FromObject"
Line
Reverse Forward
Definition of direction
for directional functions
Line protection
IED
Line as
ANSI05000753.vsd
Section 4
Analog inputs
SEMOD55055-29 v7
SEMOD55055-35 v8
57