Time overcurrent characteristic curve graphs – Basler Electric DGC-2020HD User Manual
Page 350
340
9469300990 Rev B
Table 94. 51 Time Characteristic Curve Constants
Curve
Selection
Curve Name
Trip Characteristic Constants
Reset
†
A
B
C
N
K
Q
R
S1
Short Inverse
0.2663
0.03393
1
1.2969
0.028
1
0.5
S2
Short Inverse
0.0286
0.0208
1
0.9844
0.028
1
0.094
L1
Long Inverse
5.6143
2.18592
1
1
0.028
1
15.75
L2
Long Inverse
2.3955
0
1
0.3125
0.028
1
7.8001
D
Definite Time
0.4797
0.21359
1
1.5625
0.028
1
0.875
M
Moderately Inverse
0.3022
0.1284
1
0.5
0.028
1
1.75
I1
Inverse Time
8.9341
0.17966
1
2.0938
0.028
1
9
I2
Inverse Time
0.2747
0.10426
1
0.4375
0.028
1
0.8868
V1
Very Inverse
5.4678
0.10814
1
2.0469
0.028
1
5.5
V2
Very Inverse
4.4309
0.0991
1
1.9531
0.028
1
5.8231
E1
Extremely Inverse
7.7624
0.02758
1
2.0938
0.028
1
7.75
E2
Extremely Inverse
4.9883
0.0129
1
2.0469
0.028
1
4.7742
A
Standard Inverse
0.01414
0
1
0.02
0.028
1
2
B
Very Inverse (I
2
t)
1.4636
0
1
1.0469
0.028
1
3.25
C
Extremely Inverse (I
2
t)
8.2506
0
1
2.0469
0.028
1
8
G
Long Time Inverse (I
2
t)
12.1212
0
1
1
0.028
1
29
F
Fixed Time
∗
0
1
0
0
0
1
1
46
Negative-Sequence
Overcurrent
‡
0
0
2
0.028
1
100
P
User Programmable §
0 to 600
0 to 25
0 to
1
0.5 to
2.5
0.028
0.1 to
10
0 to 30
∗ Curve F has a fixed delay of one second times the Time Dial setting.
† Instantaneous or integrating reset is selected on the Overcurrent setup screen in BESTCOMSPlus
®.
‡ Constant A is variable for the 46 curve and is determined, as necessary, based on system full-load
current setting, minimum pickup, and K factor settings.
§ The programmable curve allows for four significant digits after the decimal place for every variable.
Time Overcurrent Characteristic Curve Graphs
The figures after the tables illustrate the characteristic curves of the DGC-2020HD. Table 95 cross-
references each curve to existing electromechanical relay characteristics. Equivalent time dial settings
were calculated at a value of five times pickup.
Time Curve Characteristics
DGC-2020HD