ABB Relion 670 Series Applications Manual page 73

1MRK 511 401-UUS F
A B
CT 800/1
Wye Connected
Protected Object
ANSI06000644 V2 EN-US
Figure 15: Wye connected three-phase CT set with its wye point away from the protected object and the
residual/neutral current connected to the IED
Where:
1)
2)
3)
4)
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Bay control REC670
Application manual
C
IN
IC
IB
IA
Shows how to connect three individual phase currents from a wye connected three-phase CT set to the
three CT inputs of the IED.
Shows how to connect residual/neutral current from the three-phase CT set to the fourth input in the
IED. It shall be noted that if this connection is not made, the IED will still calculate this current internally
by vectorial summation of the three individual phase currents.
Is the TRM where these current inputs are located. It shall be noted that for all these current inputs the
following setting values shall be entered.
CTprim =800A
•
• CTsec =1A
CTStarPoint =FromObject
•
ConnectionType =Ph-N
•
The ratio of the first two parameters is only used inside the IED. The third parameter as set in this
example will have no influence on measured currents (that is, currents are already measured towards the
protected object).
Are three connections made in the Signal Matrix tool (SMT) and Application configuration tool (ACT),
which connects these three current inputs to the first three input channels on the preprocessing
function block 6). Depending on the type of functions, which need this current information, more than
one preprocessing block might be connected in parallel to these three CT inputs.
© Copyright 2017 ABB. All rights reserved
IED
3
1
1
2 AI 01 (I)
3
AI 02 (I)
4
5
AI 03 (I)
6
7
AI 04 (I)
8
9
AI 05 (I)
2 10
11
AI 06 (I)
12
6
4
SMAI2
BLOCK
^GRP2_A
^GRP2_B
^GRP2_C
^GRP2N
TYPE
5
ANSI06000644-2-en.vsd
Section 4
Analog inputs
AI3P
AI1
AI2
AI3
AI4
AIN
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