ABB Relion 670 series - Page 266

A-G B-G C-G
A-G B-G C-G
A-G B-G C-G
A-G B-G C-G
A- B
B
-
C
C-A
A- B B
-C
C-
A
A- B B-C -A
A- B B-C
C
-A
A-G B-G C-G
A- B
B
-C
C
-A
Zone 1
Zone 2
Zone 3
Zone 4
Zone 5
C
Zone 6
A-G B-G C-G
A- B
B
-
C
C-A
ANSI05000458-2-en.vsd
ANSI05000458 V2 EN-US
Figure 122: The different measuring loops at phase-to-ground fault and phase-to-phase
fault.
The use of full scheme technique gives faster operation time compared to switched schemes
which mostly uses a pickup of an overreaching element to select correct voltages and current
depending on fault type. Each distance protection zone performs like one independent distance
protection IED with six measuring elements.
7.6.6.2 Impedance characteristic
GUID-0DC94F08-9B3A-424D-9615-BD5C577344ED v1
The distance measuring zone includes six impedance measuring loops; three intended for phase-
to-ground faults, and three intended for phase-to-phase as well as, three-phase faults.
The distance measuring zone will essentially operate according to the non-directional impedance
characteristics presented in figure
123 and figure 124. The phase-to-ground characteristic is
illustrated with the full loop reach while the phase-to-phase characteristic presents the per phase
reach.
Section 7 1MRK 502 066-UUS B
Impedance protection
260
Technical manual