Catalog Add On: BETA Low-Voltage Circuit Protection ...

4
BETA Protecting
SITOR Semiconductor Fuses
SITOR, cylindrical fuse design
Series 3NC1 4..-5 with striking pin
Size: 14 mm × 51 mm
Operational class: aR
Rated voltage: 690 V AC/700 V DC
Rated current: 10 ... 50 A
Time/current characteristic curves diagram Let-through characteristics (current limitation at 50 Hz)
[s]
t VS
Virtual pre-arcing time
10
10 -3
-2
10
6
4
2
-1
10
6
4
2
0
10
6
4
2
1
10
6
10 3
6
4
2
10 2
6
4
2
6
4
2
4
4
2
10 0
Correction factor k A for breaking I 2 t value Peak arc voltage
Correction factor
1
0,8
0,6
0,4
0,2
0
0
4/48
2 4 6 10 1
10 A
15 A
20 A
25 A
30 A
32 A
40 A
50 A
2 4 6 10 2 4 6
Prospective short-circuit current p
2
100 200 300 400 500 600 700 800
Recovery voltage
Siemens ET B1 AO · 2008, Characteristic curves
I2_13412
© Siemens AG 2007
I2_13410
10 3
C
Let-through current
Peak arc voltage
10 4
6
4
2
10 3
6
4
2
10 2
6
4
2
10 1
10 1
1400
1200
1000
800
600
400
200
0
0
50 A
40 A
32 A
30 A
25 A
20 A
15 A
10 A
2 4 6 10 2 2 4 6 10 3 2 4 6 10 4 2 4 6 10 5
Prospective short-circuit current p
200
400 600
Recovery voltage
I2_13413
800
I2_13411