ABB RER670 - Example on How to Connect a Residually Connected IED

4.2.4.4 Example on how to connect a residually connected IED
SEMOD55055-163 v9
Figure 18 gives an example about the wiring of a residually connected VT to the
IED. It shall be noted that this type of VT connection presents a secondary voltage
proportional to 2U0 to the IED.
The primary rated voltage of an open Delta VT is always equal to U
Ph-E
. T
wo
series connected VT secondary windings gives a secondary voltage equal to the
sum of the two phase voltages. Thus the secondary windings of open deltaVTs may
have a secondary rating of 110/2V.
Figure
18 gives overview of 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.
L1
IED
L2
+2Uo
132
2
100
2
kV
V
132
2
100
2
kV
V
1
2
4
3
5
IEC16000152-1-en.vsdx
SMAI2
BLOCK
^GRP2L1
^GRP2L2
^GRP2L1L2
^GRP2N
AI2P
AI1
AI2
AI3
AI4
AIN
IEC16000152 V1 EN-US
Figure 18: Residually connected VT in two-phase power system
Section 4 1MRK 506 375-UEN A
Analog inputs
58 Railway application RER670 2.2 IEC
Application manual