ABB RELION REX640 Technical Manual page 781

1MRS759142 F
Figure 447: Example for busbar differential protection
Bus data:
U
n
I
n
I
kmax
10 feeders per protected zone including bus coupler and incomer.
CT data is assumed to be:
CT
R
in
U
kn
I
e
R
m
The stabilizing voltage is calculated using the formula:
REX640
Technical Manual
20 kV
2000 A
25 kA
2000/1 A
15.75 Ω
436 V
<7 mA (at U )
kn
1Ω
Protection functions
781