ABB Relion REG670, Applications Manual

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Protected Object
L1 L2 L3
IED
IN
P
INS
INS
2
IEC11000029-4-en.vsdx
4
3
C
T
1000
/1
a)
b)
(+)
(+)
(-)
(-)
(+)
(-)
1
SMAI2
BLOCK
REVROT
^GRP2L1
^GRP2L2
^GRP2L3
^GRP2N AI3P
AI1
AI2
AI3
AI4
AI N
IEC11000029 V4 EN
Figure 23: 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 23 :
CTprim= 1000 A
CTsec= 1A
CTStarPoint=ToObject
For connection (b) shown in Figure 23 :
CTprim= 1000 A
CTsec= 1A
CTStarPoint=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 DFTReference shall be
set accordingly.
4.2.3 Relationships between setting parameter Base Current, CT
rated primary current and minimum pickup of a protection
IED
Note that for all line protection applications (e.g. distance protection or line
differential protection) the parameter Base Current (i.e. IBase setting in the IED) used
by the relevant protection function, shall always be set equal to the largest rated CT
Section 4
1MRK 502 071-UEN -
Analog inputs
80 Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
Application manual