23
—
Figure 12. Application
example of busbar
differential protection
covering two zones using
standard configuration N
In the application example in Figure 12, single bus-
bar switchgear has been arranged into two bus
sections separated with bus coupler. Standard con-
figuration N is used with high-impedance differen-
tial protection for busbar and covering two zones
with two protection relays.
3
52
3
52
Δ
Y
52
Υ
or
Δ
Υ
or
Δ
3
REF615 Conf N
67P/51P/50P
50BF
67G/51G/50G
27
27R
25
AFD
3
3
REF615 Conf N
51P/50P
50BF
67/51G/50G
49F
AFD
REF615 Conf N
51P/50P
50BF
67/51G/50G
79
AFD
3
52
3
52
Δ
Y
52
Υ
or
Δ
Υ
or
Δ
3
3
REF615 Conf N
51P/50P
50BF
67/51G/50G
49F
AFD
REF615 Conf N
51P/50P
50BF
67/51G/50G
79
AFD
52
3
REF615 Conf P
67P/51P/50P
50BF
67N/51N/50N
27
27R
25
AFD
1
1
3
3
Cable
Overhead
line
Cable
Overhead
line
REF615 Conf N
67P/51P/50P
50BF
67G/51G/50G
27
27R
25
AFD
REF615 Conf N
87A
87B
87C
AFD
REF615 Conf N
87A
87B
87C
AFD
3
3
3
3
3
3
3
3
3
Stabilizing
varistor and
resistor