Table 1: P/B relays and the close-in fault currents for an IEEE 8-bus test system.

Primary relay Backup relay No. Current No. Current 1 3230 6 3230 8 6080 9 1160 8 6080 7 1880 2 5910 1 993 9 2480 10 2480 2 5910 7 1880 3 3550 2 3550 10 3880 11 2340 6 6100 5 1200 6 6100 14 1870 13 2980 8 2980 14 5190 9 1160 7 5210 5 1200 14 5190 1 993 7 5210 13 985 4 3780 3 2240 11 3700 12 3700 5 2400 4 2400 12 5890 13 985 12 5890 14 1870