GE 735

5-14 735/737 Feeder Protection Relay
GE Power Management
5.4 IAC CURVES 5 OVERCURRENT CURVES
5
5.4.2 IAC INVERSE CURVES
The trip time is given by:
where: T = trip time (in seconds) A = 0.2078 (curve shape constant)
S = curve shift multiplier B = 0.8630 (curve shape constant)
M = 735/737 curve multiplier setpoint C = 0.8000 (curve shape constant)
I = input current (in amps) D = –0.4180 (curve shape constant)
Ipu = pickup current setpoint E = 0.1947 (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 9.433 1.155 0.749 0.532 0.443 0.392 0.360 0.337 0.320 0.307 0.297 0.267 0.252
2 18.865 2.310 1.499 1.064 0.885 0.784 0.719 0.674 0.640 0.614 0.594 0.533 0.503
3 28.298 3.466 2.248 1.596 1.328 1.177 1.079 1.011 0.960 0.922 0.891 0.800 0.755
4 37.730 4.621 2.997 2.128 1.770 1.569 1.439 1.348 1.280 1.229 1.188 1.066 1.007
5 47.163 5.776 3.747 2.660 2.213 1.961 1.798 1.685 1.601 1.536 1.485 1.333 1.258
6 56.596 6.931 4.496 3.192 2.656 2.353 2.158 2.022 1.921 1.843 1.781 1.599 1.510
7 66.028 8.087 5.246 3.724 3.098 2.745 2.518 2.359 2.241 2.150 2.078 1.866 1.761
8 75.461 9.242 5.995 4.256 3.541 3.138 2.878 2.695 2.561 2.457 2.375 2.133 2.013
9 84.893 10.397 6.744 4.788 3.983 3.530 3.237 3.032 2.881 2.765 2.672 2.399 2.265
10 94.326 11.552 7.494 5.320 4.426 3.922 3.597 3.369 3.201 3.072 2.969 2.666 2.516
0.5 1 4.716 0.578 0.375 0.266 0.221 0.196 0.180 0.168 0.160 0.154 0.148 0.133 0.126
2 9.433 1.155 0.749 0.532 0.443 0.392 0.360 0.337 0.320 0.307 0.297 0.267 0.252
3 14.149 1.733 1.124 0.798 0.664 0.588 0.540 0.505 0.480 0.461 0.445 0.400 0.377
4 18.865 2.310 1.499 1.064 0.885 0.784 0.719 0.674 0.640 0.614 0.594 0.533 0.503
5 23.582 2.888 1.873 1.330 1.107 0.981 0.899 0.842 0.800 0.768 0.742 0.666 0.629
6 28.298 3.466 2.248 1.596 1.328 1.177 1.079 1.011 0.960 0.922 0.891 0.800 0.755
7 33.014 4.043 2.623 1.862 1.549 1.373 1.259 1.179 1.120 1.075 1.039 0.933 0.881
8 37.730 4.621 2.997 2.128 1.770 1.569 1.439 1.348 1.280 1.229 1.188 1.066 1.007
9 42.447 5.199 3.372 2.394 1.992 1.765 1.619 1.516 1.441 1.382 1.336 1.200 1.132
10 47.163 5.776 3.747 2.660 2.213 1.961 1.798 1.685 1.601 1.536 1.485 1.333 1.258
0.8 1 7.546 0.924 0.599 0.426 0.354 0.314 0.288 0.270 0.256 0.246 0.238 0.213 0.201
2 15.092 1.848 1.199 0.851 0.708 0.628 0.576 0.539 0.512 0.491 0.475 0.427 0.403
3 22.638 2.773 1.798 1.277 1.062 0.941 0.863 0.809 0.768 0.737 0.713 0.640 0.604
4 30.184 3.697 2.398 1.702 1.416 1.255 1.151 1.078 1.024 0.983 0.950 0.853 0.805
5 37.730 4.621 2.997 2.128 1.770 1.569 1.439 1.348 1.280 1.229 1.188 1.066 1.007
6 45.276 5.545 3.597 2.554 2.125 1.883 1.727 1.617 1.537 1.474 1.425 1.280 1.208
7 52.823 6.469 4.196 2.979 2.479 2.196 2.014 1.887 1.793 1.720 1.663 1.493 1.409
8 60.369 7.394 4.796 3.405 2.833 2.510 2.302 2.156 2.049 1.966 1.900 1.706 1.611
9 67.915 8.318 5.395 3.830 3.187 2.824 2.590 2.426 2.305 2.212 2.138 1.919 1.812
10 75.461 9.242 5.995 4.256 3.541 3.138 2.878 2.695 2.561 2.457 2.375 2.133 2.013
1.1 1 10.376 1.271 0.824 0.585 0.487 0.431 0.396 0.371 0.352 0.338 0.327 0.293 0.277
2 20.752 2.542 1.649 1.170 0.974 0.863 0.791 0.741 0.704 0.676 0.653 0.586 0.554
3 31.128 3.812 2.473 1.756 1.461 1.294 1.187 1.112 1.056 1.014 0.980 0.880 0.830
4 41.503 5.083 3.297 2.341 1.947 1.726 1.583 1.483 1.409 1.352 1.306 1.173 1.107
5 51.879 6.354 4.121 2.926 2.434 2.157 1.978 1.853 1.761 1.689 1.633 1.466 1.384
6 62.255 7.625 4.946 3.511 2.921 2.589 2.374 2.224 2.113 2.027 1.960 1.759 1.661
7 72.631 8.895 5.770 4.096 3.408 3.020 2.770 2.594 2.465 2.365 2.286 2.053 1.938
8 83.007 10.166 6.594 4.682 3.895 3.451 3.165 2.965 2.817 2.703 2.613 2.346 2.214
9 93.383 11.437 7.419 5.267 4.382 3.883 3.561 3.336 3.169 3.041 2.939 2.639 2.491
10 103.759 12.708 8.243 5.852 4.869 4.314 3.957 3.706 3.521 3.379 3.266 2.932 2.768
TSMA
B
II
pu
⁄()
C
–
----------------------------
D
II
pu
⁄()
C
–
()
2
-----------------------------------
E
II
pu
⁄()
C
–
()
3
-----------------------------------
++ +



××
=