Example How To Connect Single-Phase Ct To The Ied - ABB REQ650 Applications Manual

1MRK 505 291-UEN A
L1
CT 800/1
Star Connected
Protected Object
IEC11000026 V4 EN
Figure 27: Star connected three-phase CT set with its star point away from the protected object
4.2.3.5
Application manual
L2 L3
IN
IL3
IL2
IL1
In the example in figure 27
described example (figure
CTStarPoint of the used current inputs on the TRM (item 2 in the figure):
• CTprim=600A
• CTsec=5A
• CTStarPoint=FromObject
Inside the IED only the ratio of the first two parameters is used. The third parameter
as set in this example will negate the measured currents in order to ensure that the
currents are measured towards the protected object within the IED.

Example how to connect single-phase CT to the IED

Figure 28 gives an example how to connect the single-phase CT to the IED. It gives
an overview of the required actions by the user in order 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.
IED
2
1
3
case everything is done in a similar way as in the above
26). The only difference is the setting of the parameter
Section 4
Analog inputs
4
SMAI2
BLOCK AI3P
REVROT AI1
5
^GRP2L1 AI2
^GRP2L2 AI3
^GRP2L3 AI4
^GRP2N AI N
IEC11000026-4-en.vsdx
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