ABB Relion 670 series - Connection Examples for High Impedance Differential Protection; Connections for Three-Phase High Impedance Differential Protection

7.1.3 Connection examples for high impedance differential protection
WARNING! USE EXTREME CAUTION! Dangerously high voltages
might be present on this equipment, especially on the plate with resistors.
De-energize the primary object protected with this equipment before
connecting or disconnecting wiring or performing any maintenance. The
plate with resistors should be provided with a protective cover, mounted
in a separate box or in a locked cubicle. National law and standards shall
be followed.
7.1.3.1 Connections for three-phase high impedance differential protection
Generator, reactor or busbar differential protection is a typical application for three-phase
high impedance differential protection. Typical CT connections for three-phase high
impedance differential protection scheme are shown in figure 51.
L1
(A)
L2
(B)
L3
(C)
Protected Object
CT 1200/1
Star/Wye
Connected
L1
(A)
L2
(B)
L3
(C)
CT 1200/1
Star/Wye
Connected
7
8
9
1
0
1
1
1
2
1
2
3
4
5
6
AI01
(I)
AI02
(I)
AI03
(I)
AI04
(I)
AI05
(I)
AI06
(I)
7
6
X1
R4 R5 R6
1
2
1
2
1
2
11 12 13 14
U U U
R1
1
3
4
2
1
3
R2
2
4
1
3
R3
2
4
1 2 3 4 5 6 7
L1 (A)
L2 (B)
L3 (C)
N
3-Ph Plate with Metrosils and Resistors
2
3
5
4
X X
L1 (A)
L2 (B)
L3 (C)
N
1
IED
SMAI2
BLOCK
REVROT
^GRP2_A
^GRP2_B
^GRP2_C
^GRP2_N
G2AI3P
G2AI1
G2AI2
G2AI3
G2AI4
G2N
ANSI09000169-4-en.vsdx
ANSI09000169 V4 EN
Figure 51: CT connections for high impedance differential protection
Section 7 1MRK 506 369-UUS -
Differential protection
142 Line distance protection REL670 2.2 ANSI
Application manual