GE N60 Instruction Manual page 416

GROUPED ELEMENTS
IEEE curves
The IEEE time overcurrent curve shapes conform to industry standards and the IEEE C37.112-1996 curve classifications for
extremely, very, and moderately inverse curves. The IEEE curves are derived from the operate and reset time equations.
where
T = operate time (in seconds)
TDM = Multiplier setting
I = input current
I = Pickup Current setting
pickup
A, B, p = constants defined in the table
T = reset time in seconds (assuming energy capacity is 100% and RESET is "Timed")
RESET
t = characteristic constant defined in the table
r
Table 5-30: IEEE inverse time curve constants
IEEE curve shape
IEEE Extremely Inverse
IEEE Very Inverse
IEEE Moderately Inverse
5
Table 5-31: IEEE curve trip times (in seconds)
Multiplier Current ( I / I
(TDM)
1.5
IEEE Extremely Inverse
0.5 11.341
1.0 22.682
2.0 45.363
4.0 90.727
6.0 136.090
8.0 181.454
10.0 226.817
IEEE Very Inverse
0.5 8.090
1.0 16.179
2.0 32.358
4.0 64.716
6.0 97.074
8.0 129.432
10.0 161.790
IEEE Moderately Inverse
0.5 3.220
1.0 6.439
2.0 12.878
4.0 25.756
6.0 38.634
8.0 51.512
5-222
A B
28.2 0.1217
19.61 0.491
0.0515 0.1140
)
pickup
2.0 3.0 4.0
4.761 1.823 1.001
9.522 3.647 2.002
19.043 7.293 4.003
38.087 14.587 8.007
57.130 21.880 12.010
76.174 29.174 16.014
95.217 36.467 20.017
3.514 1.471 0.899
7.028 2.942 1.798
14.055 5.885 3.597
28.111 11.769 7.193
42.166 17.654 10.790
56.221 23.538 14.387
70.277 29.423 17.983
1.902 1.216 0.973
3.803 2.432 1.946
7.606 4.864 3.892
15.213 9.729 7.783
22.819 14.593 11.675
30.426 19.458 15.567
N60 NETWORK STABILITY AND SYNCHROPHASOR MEASUREMENT SYSTEM – INSTRUCTION MANUAL
p t
r
2.0000 29.1
2.0000 21.6
0.02000 4.85
5.0 6.0 7.0
0.648 0.464 0.355
1.297 0.927 0.709
2.593 1.855 1.418
5.187 3.710 2.837
7.780 5.564 4.255
10.374 7.419 5.674
12.967 9.274 7.092
0.654 0.526 0.450
1.308 1.051 0.900
2.616 2.103 1.799
5.232 4.205 3.598
7.849 6.308 5.397
10.465 8.410 7.196
13.081 10.513 8.995
0.844 0.763 0.706
1.688 1.526 1.412
3.377 3.051 2.823
6.753 6.102 5.647
10.130 9.153 8.470
13.507 12.204 11.294
CHAPTER 5: SETTINGS
Eq. 5-10
8.0 9.0 10.0
0.285 0.237 0.203
0.569 0.474 0.407
1.139 0.948 0.813
2.277 1.897 1.626
3.416 2.845 2.439
4.555 3.794 3.252
5.693 4.742 4.065
0.401 0.368 0.345
0.802 0.736 0.689
1.605 1.472 1.378
3.209 2.945 2.756
4.814 4.417 4.134
6.418 5.889 5.513
8.023 7.361 6.891
0.663 0.630 0.603
1.327 1.260 1.207
2.653 2.521 2.414
5.307 5.041 4.827
7.960 7.562 7.241
10.614 10.083 9.654