ABB Relion 670 series, Applications Manual

Page: 67 / 760

Transformer
protection
Transformer
Line
Line
Setting of current input:
Set parameter
CTStarPoint with
Transformer as
reference object.
Correct setting is
"ToObject"
Forward Reverse
Definition of direction
for directional functions
Line protection
Setting of current input:
Set parameter
CTStarPoint with
Transformer as
reference object.
Correct setting is
"ToObject"
Setting of current input:
Set parameter
CTStarPoint with
Line as
reference object.
Correct setting is
"FromObject"
IEC05000753=IEC05
000753=1=en=Origin
al[1].vsd
I
s
I
s
I
p
I
p
I
p
IED
IED
IEC05000753 V2 EN-US
Figure 7: Example how to set CTStarPoint parameters in the IED
The 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 the 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 v5
Two IEDs used for protection of two objects and sharing a CT.
1MRK 505 343-UEN B Section 4
Analog inputs
61
Application manual