Example 1; Example 2 - ABB REC670 Applications Manual

1MRK 511 401-UUS A
4.2.2.1
4.2.2.2
Bay control REC670 2.2 ANSI
Application manual

Example 1

Two IEDs used for protection of two objects.
Transformer
I
p
Transformer
I
s
protection
IED
Setting of current input:
Set parameter
CT_WyePoint with
Transformer as
reference object.
Correct setting is
"ToObject"
ANSI05000753 V2 EN-US
Figure 7: Example how to set CT_WyePoint parameters in the IED
Figure 7 shows the normal case where the objects have their own CTs. The settings for
CT direction 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.

Example 2

Two IEDs used for protection of two objects and sharing a CT.
Figure 8: Example how to set CT_WyePoint parameters in the IED
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.
I
p
I
s
Setting of current input:
Set parameter
CT_WyePoint with
Transformer as
reference object.
Correct setting is
"ToObject"
Analog inputs
Line
I
p
Line
Reverse Forward
Definition of direction
for directional functions
Line protection
IED
Setting of current input:
Set parameter
CT_WyePoint with
Line as
reference object.
Correct setting is
"FromObject"
ANSI05000753.vsd
Section 4
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SEMOD55055-29 v7
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