Siemens SIRIUS 3RV Series - Short-Circuit Breaking Capacity for Motor Starter Protectors in the IT System

SIRIUS 3RV2 motor starter protectors
4.10 Technical data
SIRIUS Innovations
464 System Manual, 01/2011, A8E56203870002-03
4.10.11.2 Short-circuit breaking capacity for motor starter protectors in the IT system
Short-circuit breaking capacity I
cuIT
in the IT system
3RV2 motor starter protectors are suitable for use in IT systems. The values of I
cu
and I
cs
apply for the three-pole short circuit. In the case of a double ground fault in different phases
(input and output side of a motor starter protector), the special short-circuit breaking capacity
I
cuIT
applies. The specifications listed in the table below apply for 3RV2 motor starter
protectors.
In some ranges I
cuIT
is 100 kA and 50 kA respectively. As such the motor starter protectors
are short-circuit-proof in this range.
If the short-circuit current at the installation location exceeds the motor starter protector's
specified rated service short-circuit breaking capacity, you will need to use a backup fuse.
The maximum rated current of this backup fuse is indicated in the tables. The rated short-
circuit breaking capacity then applies as specified on the fuse.
Table 4- 34 Short-circuit breaking capacity I
cuIT
in the IT system part 1
Up to 240 V AC Up to 400 V
2)
/415 V
3)
AC Rated current I
n
I
cuIT
Max. fuse (gL/gG)
4)
I
cuIT
Max. fuse (gL/gG)
4), 5)
A kA A kA A
Size S00
0.16 ... 0.4 100
1)
100
1)
0.5 100
1)
100
1)
0.63 100
1)
100
1)
0.8 100
1)
100
1)
1 100
1)
100
1)
1.25 100
1)
100
1)
1.6 100
1)
100
1)
2 100
1)
8 25
2.5 100
1)
8 25
3.2 100
1)
8 32
4 100
1)
4 32
5 100
1)
4 32
6.3 100
1)
4 50
8 100
1).
4 50
10 100
1)
4 50
12.5 100
1)
4 63
16 55 80 4 63