Siemens SINAMICS S120 Combi Manual page 53

For example S
From S
Remark:
The short-circuit power at the factory connection S
dimensioning the matching transformer.
From the rated power (S
for the matching transformer.
Table 3- 6 Engineering notes for the transformer
S120 Combi Power Module
P
n
10 kW
16 kW
20 kW
Note
Ask your local power utility company for the system fault level S
Example 1
u matching transformer = 3 %
k
S
K factory
S
K line
according to a)
S
n1
According to b)
S
n2
The matching transformer requires a rated power S
of 3%.
SINAMICS S120 Combi
Manual, 11/2017, 6SL3097-4AV00-0BP7
for 16 kW S120 Combi Power Module: S
K line
the required rated power of the matching transformer can be calculated.
K transformer
n1
Required rated power S
the isolating transform-
er/autotransformer
S ≥ 13 kVA
n
S ≥ 21 kVA
n
S ≥ 26 kVA
n
= 50000 kVA
= 16 kW • 70 • 0.73 = 820 kVA
= 1.27 • 16 kW = 21 kVA
> S ⇒ S is decisive.
n1 n2
or S ) calculated under a) and b), the higher value must be used
n2
of Required short-circuit
n
voltage u
k
U ≤ 3%
K
u ≤ 3%
k
u ≤ 3%
k
Line-side power components
3.8 Line connection versions
= 0.82 MVA = 820 kVA
K line
plays a decisive role in
K factory
Required system fault level
S
K line
S ≥ 0.7 MVA
Kline
S ≥ 1.12 MVA
K line
S ≥ 1.4 MVA
K line
.
K line
of 25 kVA for a short-circuit voltage u
n k
53