DET-653C
EntelliGuard
®
G Circuit Breaker Application Guide
24-May-12
Section 3. EntelliGuard TU Trip Unit System
©2012 General Electric All Rights Reserved
17
Table 3.4. Thermal Characteristic: Nominal Clearing and Commit Times for X Multipliers of Nominal Pickup
X=
1.5
7.2
10
12
15
Commit
Clear
Commit
Clear
Commit
Clear
Commit
Clear
Commit
Clear
Min CB
4.25
8.04
0.139
0.239
0.072
0.137
0.050
0.104
0.038
0.080
C-2
12.7
24.1
0.417
0.656
0.215
0.352
0.149
0.253
0.095
0.172
C-3
25.5
48.1
0.83
1.28
0.430
0.674
0.298
0.476
0.190
0.315
C-4
34.0
64.1
1.11
1.70
0.57
0.89
0.40
0.62
0.254
0.410
C-5
51.0
96.2
1.67
2.53
0.86
1.32
0.60
0.92
0.38
0.60
C-6
67.9
128
2.22
3.4
1.15
1.75
0.79
1.22
0.51
0.79
C-7
84.9
160
2.78
4.2
1.43
2.18
0.99
1.52
0.63
0.98
C-8
102
192
3.33
5.0
1.72
2.61
1.19
1.81
0.76
1.17
C-9
119
224
3.89
5.9
2.01
3.03
1.39
2.11
0.89
1.36
C-10
136
256
4.44
6.7
2.29
3.46
1.59
2.41
1.02
1.55
C-11
153
289
5.00
7.5
2.58
3.89
1.79
2.71
1.14
1.74
C-12
170
321
5.56
8.4
2.87
4.32
1.99
3.00
1.27
1.93
C-13
204
385
6.67
10.0
3.44
5.18
2.38
3.60
1.52
2.31
C-14
238
449
7.78
11.7
4.01
6.04
2.78
4.19
1.78
2.69
C-15
272
513
8.89
13.4
4.59
6.90
3.18
4.79
2.03
3.07
C-16
306
577
10.0
15.0
5.16
7.76
3.58
5.38
2.29
3.45
C-17
340
641
11.1
16.7
5.73
8.61
3.97
5.98
2.54
3.83
C-18
374
705
12.2
18.4
6.30
9.47
4.37
6.57
2.79
4.21
C-19
408
769
13.3
20.0
6.88
10.3
4.77
7.17
3.05
4.59
C-20
442
833
14.4
21.7
7.45
11.2
5.17
7.76
3.30
4.97
C-21
476
898
15.6
23.4
8.02
12.0
5.56
8.36
3.56
5.35
Max CB
510
962
16.7
25.1
8.60
12.9
5.96
8.95
3.81
5.73
•
Algorithm will not commit below 1.5 cycles, clearing time will not be less than 0.08sec.
•
Maximum LT curve is 15XLTPU for Envelope 1 and 2 devices, 10XLTPU for Envelope 3 devices.
•
Actual Long Time pickup is 112% of nominal pickup.
F
use-Shaped Steep Long Time Overcurrent
The optional steeper fuse characteristic is a straight line
K=I
4
t shape for application in systems where fuses and
circuit breakers are used together. Twenty-two different
time bands are available in each trip unit.
Figure 3.4 displays minimum and maximum bands. Table 3.6
displays the nominal time delays for each of the 22 bands at
various multiples of nominal current pickup.
Drawn bands also include a 30 ms constant time, which
accounts for the slight widening evident in the time current
curve at the lower (right) end of the faster (lower) time bands.
Figure 3.4. Fuse Characteristic: Maximum and Minimum
Long Time Delay Bands for a 1000A Long Time Pickup
Table 3.5.
Breaker Type
TCC
EntelliGuard G:
DES-091
WavePro, PBII, PBI, AK, AKR,
Conv Kits
DES-096
