GROUPED ELEMENTS
IAC curve shape
IAC Short Inverse
Table 5-34: GE type IAC curve trip times
Multiplier
Current ( I / I
(TDM)
1.5
IAC Extremely Inverse
0.5
1.699
1.0
3.398
2.0
6.796
4.0
13.591
6.0
20.387
8.0
27.183
10.0
33.979
IAC Very Inverse
0.5
1.451
1.0
2.901
2.0
5.802
4.0
11.605
6.0
17.407
8.0
23.209
5
10.0
29.012
IAC Inverse
0.5
0.578
1.0
1.155
2.0
2.310
4.0
4.621
6.0
6.931
8.0
9.242
10.0
11.552
IAC Short Inverse
0.5
0.072
1.0
0.143
2.0
0.286
4.0
0.573
6.0
0.859
8.0
1.145
10.0
1.431
2
I
t curves
2
The I
t curves are derived as follows:
where
5-218
A
B
0.0428
0.0609
)
pickup
2.0
3.0
4.0
0.749
0.303
0.178
1.498
0.606
0.356
2.997
1.212
0.711
5.993
2.423
1.422
8.990
3.635
2.133
11.987
4.846
2.844
14.983
6.058
3.555
0.656
0.269
0.172
1.312
0.537
0.343
2.624
1.075
0.687
5.248
2.150
1.374
7.872
3.225
2.061
10.497
4.299
2.747
13.121
5.374
3.434
0.375
0.266
0.221
0.749
0.532
0.443
1.499
1.064
0.885
2.997
2.128
1.770
4.496
3.192
2.656
5.995
4.256
3.541
7.494
5.320
4.426
0.047
0.035
0.031
0.095
0.070
0.061
0.190
0.140
0.123
0.379
0.279
0.245
0.569
0.419
0.368
0.759
0.559
0.490
0.948
0.699
0.613
C
D
0.6200
–0.0010
5.0
6.0
7.0
0.123
0.093
0.074
0.246
0.186
0.149
0.491
0.372
0.298
0.983
0.744
0.595
1.474
1.115
0.893
1.966
1.487
1.191
2.457
1.859
1.488
0.133
0.113
0.101
0.266
0.227
0.202
0.533
0.453
0.405
1.065
0.906
0.810
1.598
1.359
1.215
2.131
1.813
1.620
2.663
2.266
2.025
0.196
0.180
0.168
0.392
0.360
0.337
0.784
0.719
0.674
1.569
1.439
1.348
2.353
2.158
2.022
3.138
2.878
2.695
3.922
3.597
3.369
0.028
0.027
0.026
0.057
0.054
0.052
0.114
0.108
0.105
0.228
0.217
0.210
0.341
0.325
0.314
0.455
0.434
0.419
0.569
0.542
0.524
L30 LINE CURRENT DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
CHAPTER 5: SETTINGS
E
t
r
0.0221
0.222
8.0
9.0
10.0
0.062
0.053
0.046
0.124
0.106
0.093
0.248
0.212
0.185
0.495
0.424
0.370
0.743
0.636
0.556
0.991
0.848
0.741
1.239
1.060
0.926
0.093
0.087
0.083
0.186
0.174
0.165
0.372
0.349
0.331
0.745
0.698
0.662
1.117
1.046
0.992
1.490
1.395
1.323
1.862
1.744
1.654
0.160
0.154
0.148
0.320
0.307
0.297
0.640
0.614
0.594
1.280
1.229
1.188
1.921
1.843
1.781
2.561
2.457
2.375
3.201
3.072
2.969
0.026
0.025
0.025
0.051
0.050
0.049
0.102
0.100
0.099
0.204
0.200
0.197
0.307
0.301
0.296
0.409
0.401
0.394
0.511
0.501
0.493
Eq. 5-17