ABB REB670 - Direct Grounded System

3V
0
V
_
A
V_B
V
_
C
V
_
B
F
V
_C
F
V
_
C
F
ANSI07000190-1-en.vsd
ANSI07000190 V1 EN-US
Figure 110: Ground fault in Non-effectively grounded systems
8.3.3.5 Direct grounded system
GUID-EA622F55-7978-4D1C-9AF7-2BAB5628070A v8
In direct grounded systems, an ground fault on one phase is indicated by voltage
collapse in that phase. The other healthy phase will still have normal phase-to-ground
voltage. The residual sum will have the same value as the remaining phase-to-ground
voltage, which is shown in Figure
111.
V
_
A
V_
B
V
_C
V
_A
F
I
L
1
F
V_
B
V
_C
3V
0
ANSI07000189-1-en.vsd
ANSI07000189 V1 EN-US
Figure 111: Ground fault in Direct grounded system
1MRK 505 370-UUS A Section 8
Voltage protection
Busbar protection REB670 2.2 ANSI 253
Application manual