Siemens SINAMICS G120D Series - Page 38

Installation
4.2 Electrical Installation
Example
In one installation, either the inverters of group ① or the inverters of group ② are in
operation, but never both groups
① and ② simultaneously.
Figure 4-7 Protection of two inverter groups via a shared 400-V feeder
The sum of the rated input currents is:
● Group
①: 7.2 A + 7.2 A + 9.5 A = 23.9 A ≤ 24 A
● Group
①: 17.7 A + 3.8 A + 2.1 A = 23.6 A ≤ 24 A
You can power all the inverters through a shared fuse.
Feeder protection according to IEC
Table 4- 5 Feeder protection according to IEC
Max. rated current of the protec-
tion device
Article No. of the fuse
Article No. of the circuit breaker
25 A 3NA3810 3RV2021…, 3RV1031…,
3RV2031…
30 A
-
3RV1742
Feeder protection according to UL standards
Use in North America requires protection devices that meet UL standards as detailed in the
following tables.
Table 4- 6 Overview of the approved protection devices according to UL standards
Protection device
UL category
Fuses of any manufacturer with faster tripping characteristic than class RK5, e.g.
class J, time, CC, G, or CF
JDDZ
SIEMENS circuit breaker
DIVQ
Intrinsically safe SIEMENS circuit breaker
NKJH
Converter with control units CU240D-2
38 Operating Instructions, 04/2015, FW V4.7.3, A5E34262100B AB