230
D90
PLUS
LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
GROUPED PROTECTION ELEMENTS
CHAPTER 7: PROTECTION
Table 10: GE type IAC inverse time curve constants
Table 11: GE type IAC curve trip times (in seconds)
IAC curve shape
A
B
C
D
E
t
r
IAC extreme inverse
0.0040
0.6379
0.6200
1.7872
0.2461
6.008
IAC very inverse
0.0900
0.7955
0.1000
–1.2885
7.9586
4.678
IAC inverse
0.2078
0.8630
0.8000
–0.4180
0.1947
0.990
IAC short inverse
0.0428
0.0609
0.6200
–0.0010
0.0221
0.222
Multiplier
(TDM)
Current (
I
/
I
pickup
)
1.5
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
IAC extremely inverse
0.5
1.699
0.749
0.303
0.178
0.123
0.093
0.074
0.062
0.053
0.046
1.0
3.398
1.498
0.606
0.356
0.246
0.186
0.149
0.124
0.106
0.093
2.0
6.796
2.997
1.212
0.711
0.491
0.372
0.298
0.248
0.212
0.185
4.0
13.591 5.993
2.423
1.422
0.983
0.744
0.595
0.495
0.424
0.370
6.0
20.387 8.990
3.635
2.133
1.474
1.115
0.893
0.743
0.636
0.556
8.0
27.183 11.987 4.846
2.844
1.966
1.487
1.191
0.991
0.848
0.741
10.0
33.979 14.983 6.058
3.555
2.457
1.859
1.488
1.239
1.060
0.926
IAC very inverse
0.5
1.451
0.656
0.269
0.172
0.133
0.113
0.101
0.093
0.087
0.083
1.0
2.901
1.312
0.537
0.343
0.266
0.227
0.202
0.186
0.174
0.165
2.0
5.802
2.624
1.075
0.687
0.533
0.453
0.405
0.372
0.349
0.331
4.0
11.605 5.248
2.150
1.374
1.065
0.906
0.810
0.745
0.698
0.662
6.0
17.407 7.872
3.225
2.061
1.598
1.359
1.215
1.117
1.046
0.992
8.0
23.209 10.497 4.299
2.747
2.131
1.813
1.620
1.490
1.395
1.323
10.0
29.012 13.121 5.374
3.434
2.663
2.266
2.025
1.862
1.744
1.654
IAC inverse
0.5
0.578
0.375
0.266
0.221
0.196
0.180
0.168
0.160
0.154
0.148
1.0
1.155
0.749
0.532
0.443
0.392
0.360
0.337
0.320
0.307
0.297
2.0
2.310
1.499
1.064
0.885
0.784
0.719
0.674
0.640
0.614
0.594
4.0
4.621
2.997
2.128
1.770
1.569
1.439
1.348
1.280
1.229
1.188
6.0
6.931
4.496
3.192
2.656
2.353
2.158
2.022
1.921
1.843
1.781
8.0
9.242
5.995
4.256
3.541
3.138
2.878
2.695
2.561
2.457
2.375
10.0
11.552 7.494
5.320
4.426
3.922
3.597
3.369
3.201
3.072
2.969
IAC short inverse
0.5
0.072
0.047
0.035
0.031
0.028
0.027
0.026
0.026
0.025
0.025
1.0
0.143
0.095
0.070
0.061
0.057
0.054
0.052
0.051
0.050
0.049
2.0
0.286
0.190
0.140
0.123
0.114
0.108
0.105
0.102
0.100
0.099
4.0
0.573
0.379
0.279
0.245
0.228
0.217
0.210
0.204
0.200
0.197
6.0
0.859
0.569
0.419
0.368
0.341
0.325
0.314
0.307
0.301
0.296
8.0
1.145
0.759
0.559
0.490
0.455
0.434
0.419
0.409
0.401
0.394
10.0
1.431
0.948
0.699
0.613
0.569
0.542
0.524
0.511
0.501
0.493