FAULT_DIR gives the detected direction of the fault during fault situations, that is,
when the START output is active.
Self-polarizing as polarizing method
Table 241: Equations for calculating angle difference for self-polarizing method
Faulted
phases
Used fault
current
Used
polarizing
voltage
Angle difference
A I
A
U
A
ANGLE A U I
A
A
RCA
_ ( ) - ( ) - =
ϕ ϕ ϕ
GUID-60308BBA-07F8-4FB4-A9E8-3850325E368C V2 EN
B I
B
U
B
ANGLE B U I
B
B
RCA
_ ( ) - ( ) - =
ϕ ϕ ϕ
GUID-9AF57A77-F9C6-46B7-B056-AC7542EBF449 V2 EN
C I
C
U
C
ANGLE C U I
C
C
RCA
_ ( ) - ( ) - =
ϕ ϕ ϕ
GUID-51FEBD95-672C-440F-A678-DD01ABB2D018 V2 EN
A - B I
A
- I
B
U
AB
ANGLE A U I I
AB
A B
RCA
_ ( ) - ( - ) - =
ϕ ϕ ϕ
GUID-7DA1116D-86C0-4D7F-AA19-DCF32C530C4C V2 EN
B - C I
B
- I
C
U
BC
ANGLE B U I I
BC
B C
RCA
_ ( ) - ( - ) - =
ϕ ϕ ϕ
GUID-3E9788CA-D2FC-4FC4-8F9E-1466F3775826 V2 EN
C - A I
C
- I
A
U
CA
ANGLE C U I I
CA
C A
RCA
_ ( ) - ( - ) - =
ϕ ϕ ϕ
GUID-EFD80F78-4B26-46B6-A5A6-CCA6B7E20C6E V2 EN
In an example case of the phasors in a single-phase earth fault where the faulted phase
is phase A, the angle difference between the polarizing quantity U
A
and operating
quantity I
A
is marked as φ. In the self-polarization method, there is no need to rotate
the polarizing quantity.
GUID-C648173C-D8BB-4F37-8634-5D4DC7D366FF V1 EN
Figure 125: Single-phase earth fault, phase A
Section 4 1MRS758755 A
Protection functions
232 REC615 and RER615
Technical Manual
To Next Page
Loading...
