ABB REC670 Applications Manual page 83

1MRK 511 401-UUS A
Bay control REC670 2.2 ANSI
Application manual
For correct terminal designations, see the connection diagrams valid for
the delivered IED.
Protected Object
A B C
INS
a)
b)
INS
ANSI11000029 V3 EN-US
Figure 18: Connections for single-phase CT input
Where:
1) shows how to connect single-phase CT input in the IED.
2) is TRM where these current inputs are located. It shall be noted that for all these current
inputs the following setting values shall be entered.
For connection (a) shown in Fgure 18:
CTprim = 1000 A
CTsec = 1A
CTWyePoint = ToObject
For connection (b) shown in Figure 18:
CTprim = 1000 A
CTsec = 1A
CTWyePoint = FromObject
3) shows the connection made in SMT tool, which connect this CT input to the fourth input
channel of the preprocessing function block 4).
4) is a Preprocessing block that has the task to digitally filter the connected analog inputs and
calculate values. The calculated values are then available for all built-in protection and
control functions within the IED, which are connected to this preprocessing function block.
If frequency tracking and compensation is required (this feature is typically required only for
IEDs installed in the power plants) then the setting parameters
accordingly.
IED
1
(+)
(+)
(-)
(+)
(-)
(-)
Section 4
Analog inputs
2
SMAI_20_2
BLOCK
REVROT
^GRP2_A
^GRP2_B
^GRP2_C
^GRP2_N
3
ANSI11000029-3-en.vsd
DFTReference shall be set
4
AI3P
AI1
AI2
AI3
AI4
AIN
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