Siemens SINAMICS S120 Manual page 144

Line connection and line-side power components
3.11 Line connection variants
Table 3- 34 Engineering information for transformers for Basic Line Modules
Rated power P
n
20 kW
40 kW
100 kW
Note
Ask your local power utility company for the short-circuit power at the plant connection S
factory
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%.
Example 2:
u matching transformer = 1 %
k
S
K factory
S
K line
According to a)
S
n1
According to b)
S
n1
The matching transformer requires a rated power S
of 1%.
144
Required rated power of the
isolating transformer / auto-
transformer
S (1.27 • P )
n n
≥ 26 kVA
≥ 51 kVA
≥ 127 kVA
.
= 50000 kVA
= 16 kW • 70 • 0.73 = 820 kVA
= 1.27 • 16 kW = 21 kVA
> S ⇒ S is decisive.
n1 n2
= 50000 kVA
= 16 kW • 70 • 0.73 = 820 kVA
= 1.27 • 16 kW = 21 kVA
> S ⇒ S is decisive.
n2 n1
Required short-circuit volt-
age U
k
≤ 10%
≤ 10%
≤ 10%
of 25 kVA for a short-circuit voltage u
n
of 21 kVA for a short-circuit voltage u
n
Manual, (GH2), 07/2016, 6SL3097-4AC00-0BP8
Minimum system fault level
required
S (30 • P )
K line n
≥ 0.6 MVA
≥ 1.2 MVA
≥ 3.0 MVA
K
Booksize Power Units
k
k