GE 750 Instruction Manual page 130

750/760
Feeder Management Relay
Table 5–6: ANSI Curve Trip Times (in seconds)
Multiplier
(TDM)
1.5 2.0
ANSI Extremely Inverse
0.5 2.000 0.872
1.0 4.001 1.744
2.0 8.002 3.489
4.0 16.004 6.977
6.0 24.005 10.466
8.0 32.007 13.955
10.0 40.009 17.443
ANSI Very Inverse
0.5 1.567 0.663
1.0 3.134 1.325
2.0 6.268 2.650
4.0 12.537 5.301
6.0 18.805 7.951
8.0 25.073 10.602
10.0 31.341 13.252
ANSI Normally Inverse
0.5 2.142 0.883
1.0 4.284 1.766
2.0 8.568 3.531
4.0 17.137 7.062
6.0 25.705 10.594
8.0 34.274 14.125
10.0 42.842 17.656
ANSI Moderately Inverse
0.5 0.675 0.379
1.0 1.351 0.757
2.0 2.702 1.515
4.0 5.404 3.030
6.0 8.106 4.544
8.0 10.807 6.059
10.0 13.509 7.574
5–34
ANSI Curves:
The ANSI time overcurrent curve shapes conform to industry standards and the
ANSI C37.90 curve classifications for extremely, very, and moderately inverse. The
ANSI curves are derived from the following formula:
⎛
T M × A
⎜
= + ----------------------------- -
⎝
( I I ⁄
pu
where: T = trip time (seconds); M = multiplier value; I = input current;
I = pickup current setpoint; A, B, C, D, E = constants
pickup
Table 5–5: ANSI Curve Constants
ANSI Curve Shape
ANSI Extremely Inverse
ANSI Very Inverse
ANSI Normally Inverse
ANSI Moderately Inverse
Current ( I / I
3.0 4.0 5.0
0.330 0.184 0.124
0.659 0.368 0.247
1.319 0.736 0.495
2.638 1.472 0.990
3.956 2.208 1.484
5.275 2.944 1.979
6.594 3.680 2.474
0.268 0.171 0.130
0.537 0.341 0.260
1.074 0.682 0.520
2.148 1.365 1.040
3.221 2.047 1.559
4.295 2.730 2.079
5.369 3.412 2.599
0.377 0.256 0.203
0.754 0.513 0.407
1.508 1.025 0.814
3.016 2.051 1.627
4.524 3.076 2.441
6.031 4.102 3.254
7.539 5.127 4.068
0.239 0.191 0.166
0.478 0.382 0.332
0.955 0.764 0.665
1.910 1.527 1.329
2.866 2.291 1.994
3.821 3.054 2.659
4.776 3.818 3.324
http://www.GEmultilin.com
B D
+ ------------------------------------- - + ------------------------------------- -
2
( ( I I ⁄ ) C ) ( ( I I
) C
–
–
pu
A B
0.0399 0.2294 0.5000
0.0615 0.7989 0.3400
0.0274 2.2614 0.3000
0.1735 0.6791 0.8000
)
pickup
6.0 7.0
0.093 0.075
0.185 0.149
0.371 0.298
0.742 0.596
1.113 0.894
1.483 1.192
1.854 1.491
0.108 0.094
0.216 0.189
0.432 0.378
0.864 0.755
1.297 1.133
1.729 1.510
2.161 1.888
0.172 0.151
0.344 0.302
0.689 0.604
1.378 1.208
2.067 1.812
2.756 2.415
3.445 3.019
0.151 0.141
0.302 0.281
0.604 0.563
1.208 1.126
1.812 1.689
2.416 2.252
3.020 2.815
S5 Protection
⎞
E
⎟
(EQ 5.2)
3
⎠
⁄ ) C )
–
pu
C D E
3.0094 0.7222
–0.2840 4.0505
–4.1899 9.1272
–0.0800 0.1271
8.0 9.0 10.0
0.063 0.055 0.049
0.126 0.110 0.098
0.251 0.219 0.196
0.503 0.439 0.393
0.754 0.658 0.589
1.006 0.878 0.786
1.257 1.097 0.982
0.085 0.078 0.073
0.170 0.156 0.146
0.340 0.312 0.291
0.680 0.625 0.583
1.020 0.937 0.874
1.360 1.250 1.165
1.700 1.562 1.457
0.135 0.123 0.113
0.270 0.246 0.226
0.541 0.492 0.452
1.082 0.983 0.904
1.622 1.475 1.356
2.163 1.967 1.808
2.704 2.458 2.260
0.133 0.128 0.123
0.267 0.255 0.247
0.533 0.511 0.493
1.066 1.021 0.986
1.600 1.532 1.479
2.133 2.043 1.972
2.666 2.554 2.465
GE Multilin