WEG SSW-07 User Manual - page 34
of
53
Chapter 4 - SettING the SSW-07
33
English
Time t(s)
1000
100
10
1
1x 2x 3x 4x 5x 6x 7x 8x 9x S.F.=1
Class 30
Class 25
Class 20
Class 15
Class 10
Class 5
x In motor
Current
0.1
Figure 4.9
- Motor protection thermal classes in hot condition at 100 % ln
Motor
Current
Class
30
20
10
3xIn
34.4 s
23.6 s
11.8 s
5xIn
12.6 s
8.4 s
4.2 s
7xIn
6.4 s
4.2 s
2.1 s
table 4.3
- Motor protection thermal class time in hot condition
Current in %
of In of the motor
Factor
0 % (cold condition)
1
20 %
0.87
40 %
0.74
60 %
0.61
80 %
0.48
100 % (rated load)
0.35
table 4.4
- Multiplication factor of the thermal class times in cold condition to
obtain the thermal class times in hot condition