GE 735

5-16 735/737 Feeder Protection Relay
GE Power Management
5.4 IAC CURVES 5 OVERCURRENT CURVES
5
5.4.3 IAC VERY INVERSE CURVES
The trip time is given by:
where: T = trip time (in seconds) A = 0.090 (curve shape constant)
S = curve shift multiplier B = 0.796 (curve shape constant)
M = 735/737 curve multiplier setpoint C = 0.100 (curve shape constant)
I = input current (in amps) D = –1.289 (curve shape constant)
Ipu = pickup current setpoint E = 7.959 (curve shape constant)
SHIFT
S
CURVE
M
CURRENT (per unit I /I
0
)
1.05 1.50 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 15.00 20.00
1 1 8.782 2.901 1.312 0.537 0.343 0.266 0.227 0.202 0.186 0.174 0.165 0.140 0.128
2 17.564 5.802 2.624 1.075 0.687 0.533 0.453 0.405 0.372 0.349 0.331 0.280 0.255
3 26.347 8.704 3.936 1.612 1.030 0.799 0.680 0.607 0.559 0.523 0.496 0.420 0.383
4 35.129 11.605 5.248 2.150 1.374 1.065 0.906 0.810 0.745 0.698 0.662 0.560 0.511
5 43.911 14.506 6.560 2.687 1.717 1.332 1.133 1.012 0.931 0.872 0.827 0.700 0.639
6 52.693 17.407 7.872 3.225 2.061 1.598 1.359 1.215 1.117 1.046 0.992 0.840 0.766
7 61.475 20.308 9.185 3.762 2.404 1.864 1.586 1.417 1.303 1.221 1.158 0.980 0.894
8 70.257 23.209 10.497 4.299 2.747 2.131 1.813 1.620 1.490 1.395 1.323 1.120 1.022
9 79.040 26.111 11.809 4.837 3.091 2.397 2.039 1.822 1.676 1.570 1.489 1.260 1.150
10 87.822 29.012 13.121 5.374 3.434 2.663 2.266 2.025 1.862 1.744 1.654 1.400 1.277
0.5 1 4.391 1.451 0.656 0.269 0.172 0.133 0.113 0.101 0.093 0.087 0.083 0.070 0.064
2 8.782 2.901 1.312 0.537 0.343 0.266 0.227 0.202 0.186 0.174 0.165 0.140 0.128
3 13.173 4.352 1.968 0.806 0.515 0.399 0.340 0.304 0.279 0.262 0.248 0.210 0.192
4 17.564 5.802 2.624 1.075 0.687 0.533 0.453 0.405 0.372 0.349 0.331 0.280 0.255
5 21.955 7.253 3.280 1.344 0.859 0.666 0.566 0.506 0.465 0.436 0.414 0.350 0.319
6 26.347 8.704 3.936 1.612 1.030 0.799 0.680 0.607 0.559 0.523 0.496 0.420 0.383
7 30.738 10.154 4.592 1.881 1.202 0.932 0.793 0.709 0.652 0.610 0.579 0.490 0.447
8 35.129 11.605 5.248 2.150 1.374 1.065 0.906 0.810 0.745 0.698 0.662 0.560 0.511
9 39.520 13.055 5.904 2.418 1.545 1.198 1.020 0.911 0.838 0.785 0.744 0.630 0.575
10 43.911 14.506 6.560 2.687 1.717 1.332 1.133 1.012 0.931 0.872 0.827 0.700 0.639
0.8 1 7.026 2.321 1.050 0.430 0.275 0.213 0.181 0.162 0.149 0.140 0.132 0.112 0.102
2 14.051 4.642 2.099 0.860 0.549 0.426 0.363 0.324 0.298 0.279 0.265 0.224 0.204
3 21.077 6.963 3.149 1.290 0.824 0.639 0.544 0.486 0.447 0.419 0.397 0.336 0.307
4 28.103 9.284 4.199 1.720 1.099 0.852 0.725 0.648 0.596 0.558 0.529 0.448 0.409
5 35.129 11.605 5.248 2.150 1.374 1.065 0.906 0.810 0.745 0.698 0.662 0.560 0.511
6 42.154 13.926 6.298 2.580 1.648 1.278 1.088 0.972 0.894 0.837 0.794 0.672 0.613
7 49.180 16.247 7.348 3.010 1.923 1.491 1.269 1.134 1.043 0.977 0.926 0.784 0.715
8 56.206 18.568 8.397 3.439 2.198 1.705 1.450 1.296 1.192 1.116 1.059 0.896 0.817
9 63.232 20.889 9.447 3.869 2.473 1.918 1.631 1.458 1.341 1.256 1.191 1.008 0.920
10 70.257 23.209 10.497 4.299 2.747 2.131 1.813 1.620 1.490 1.395 1.323 1.120 1.022
1.1 1 9.660 3.191 1.443 0.591 0.378 0.293 0.249 0.223 0.205 0.192 0.182 0.154 0.141
2 19.321 6.383 2.887 1.182 0.756 0.586 0.498 0.445 0.410 0.384 0.364 0.308 0.281
3 28.981 9.574 4.330 1.773 1.133 0.879 0.748 0.668 0.614 0.576 0.546 0.462 0.422
4 38.642 12.765 5.773 2.365 1.511 1.172 0.997 0.891 0.819 0.767 0.728 0.616 0.562
5 48.302 15.956 7.216 2.956 1.889 1.465 1.246 1.113 1.024 0.959 0.910 0.770 0.703
6 57.962 19.148 8.660 3.547 2.267 1.758 1.495 1.336 1.229 1.151 1.092 0.924 0.843
7 67.623 22.339 10.103 4.138 2.644 2.051 1.745 1.559 1.434 1.343 1.274 1.078 0.984
8 77.283 25.530 11.546 4.729 3.022 2.344 1.994 1.782 1.638 1.535 1.456 1.232 1.124
9 86.944 28.722 12.990 5.320 3.400 2.637 2.243 2.004 1.843 1.727 1.638 1.386 1.265
10 96.604 31.913 14.433 5.912 3.778 2.930 2.492 2.227 2.048 1.918 1.820 1.540 1.405
TSMA
B
II
pu
⁄()
C
–
----------------------------
D
II
pu
⁄()
C
–
()
2
-----------------------------------
E
II
pu
⁄()
C
–
()
3
-----------------------------------
++ +



××
=