ABB RELION REB670, Applications Manual

Page: 75 / 554

4.2.2.1 Example 1
SEMOD55055-23 v6
Two IEDs used for protection of two objects.
Transformer
protection
Transformer
Line
Line
Setting of current input:
Set parameter
CT_WyePoint with
Transformer as
reference object.
Correct setting is
"ToObject"
Forward Reverse
Definition of direction
for directional functions
Line protection
I
s
I
s
I
p
I
p
I
p
IED
IED
Setting of current input:
Set parameter
CT_WyePoint with
Transformer as
reference object.
Correct setting is
"ToObject"
Setting of current input:
Set parameter
CT_WyePoint with
Line as
reference object.
Correct setting is
"FromObject"
ANSI05000753.vsd
ANSI05000753 V2 EN-US
Figure 15: Example how to set CT_WyePoint parameters in the IED
Figure 15 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.
4.2.2.2 Example 2
SEMOD55055-29 v7
Two IEDs used for protection of two objects and sharing a CT.
Figure 16: 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.
1MRK 505 370-UUS A
Section 4
Analog inputs
Busbar protection REB670 2.2 ANSI 69
Application manual