Setting Of Voltage Channels - ABB REC650 Applications Manual

Section 4
Analog inputs
A B
CT 800/1
Star Connected
Protected Object
ANSI11000026 V4 EN
Figure 20: Wye connected three-phase CT set with its star point away from the protected object
4.2.4
70
C
IC
IB
IA
In the example in figure 20
described example (figure
CTStarPoint of the used current inputs on the TRM (item 2 in the figure):
• CTprim=600A
• CTsec=5A
• CTWyePoint=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.

Setting of voltage channels

As the IED uses primary system quantities the main VT ratios must be known to the IED.
This is done by setting the two parameters VTsec and VTprim for each voltage channel.
The phase-to-phase value can be used even if each channel is connected to a phase-to-
ground voltage from the VT.
IED
2
3
1
case everything is done in a similar way as in the above
19). The only difference is the setting of the parameter
1MRK 511 286-UUS A
4
SMAI_20_2
BLOCK AI3P
REVROT AI1
5
^GRP2L1 AI2
^GRP2L2 AI3
^GRP2L3 AI4
^GRP2N AIN
ANSI11000026-4-en.vsd
Application manual