Chapter 6 - Current Protection Functions
3.1.4
IEC AND IEEE INVERSE CURVES
IEC Standard Inverse Curve
1000
100
10
1
0.1
0.01
0.5
5
Current in Multiples of Setting
E00757
Figure 22: IEC standard and very inverse curves
IEC Extremely Inverse Curve
1000
100
10
1
0.1
0.01
0.5
5
Current in Multiples of Setting
E00758
Figure 23: IEC Extremely inverse and IEEE moderate inverse curves
90
1000
100
TMS
0.025
0.075
10
0.100
0.300
1
0.500
0.700
0.900
0.1
1.000
1.200
0.01
50
0.5
1000
TMS
TMS
100
0.025
0.075
10
0.100
0.300
0.500
1
0.700
0.900
0.1
1.000
1.200
0.01
0.5
50
IEC Very Inverse Curve
5
Current in Multiples of Setting
IEEE Moderate Inverse Curve
5
Current in Multiples of Setting
P24xM-TM-EN-2.1
P24xM
TMS
TMS
0.025
0.075
0.100
0.300
0.500
0.700
0.900
1.000
1.200
50
0.05
0.5
1
5
10
30
50
70
100
50