Siemens siprotec 7SA6 - Page 664

Technical Data
10-36 7SA6 Manual
C53000-G1176-C133-1
Figure 10-6 Tripping characteristic of the thermal overload protection
1
0.3
0.1
1 2 3 5 10 12
100
20
10
5
2
0.5
0.2
0.05
t [min]
t [min]
I / (k ·I
N
)
1000
1
0.3
0.1
100
20
10
5
2
0.5
0.2
0.05
[min]
3
30
30
3
Parameter:
Setting Value;
Time Factor
20
200
500
100
50
10
5
2
1
4 6 7 8
50
t τ
I
k I
N
⋅
--------------


2
I
k I
N
⋅
--------------


2
1–
--------------------------------
ln ⋅=
without Previous Load Current:
I / (k ·I
N
)
1 2 3 5 10 12 4 6 7 8
with 90 % Previous Load Current:
t τ
I
k I
N
⋅
--------------


2
I
pre
k I
N
⋅
--------------



2
–
I
k I
N
⋅
--------------


2
1–
---------------------------------------------------
ln ⋅=
50
Parameter:
Setting Value;
Time Factor
1000
500
200
100
50
20
10
5
2
1
τ [min]
τ [min]
[min]