ABB ret650, Applications Manual

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It is recommended to:
• use 1A rated CT input into the IED in order to connect CTs
with 1A and 2A secondary rating
• use 5A rated CT input into the IED in order to connect CTs
with 5A and 10A secondary rating
4.2.2.5 Example on how to connect a star connected three-phase CT set to
the IED
SEMOD55055-352 v11
Figure 11 gives an example about the wiring of a star connected two-phase CT set
to the IED. It gives an overview of the actions which are needed to make this
measurement available to the built-in protection and control functions within the
IED as well.
For correct terminal designations, see the connection diagrams
valid for the delivered IED.
L1
IL
1
IL
2
IL
3
L2 L3
Protected Object
CT 600/5
Star Connected
IL1
IL2
IL3
IED
IEC13000002-4-en.vsdx
1
2
3
4
SMAI2
BLOCK
REVROT
^GRP2L1
^GRP2L2
^GRP2L3
^GRP2N AI3P
AI1
AI2
AI3
AI4
AI N
5
IN
IEC13000002 V4 EN-US
Figure 11: Star connected three-phase CT set with star point towards the protected object
Section 4
1MRK 504 169-UEN A
Analog inputs
44 Transformer protection RET650 2.2 IEC
Application manual