Siemens Sinamics S120 Manual page 145

Rated power of the used
Active Module P
n
Rated power of the used
Basic Line Module 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
plant
Example 1
u matching transformer = 3%,
k
S
K plant
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 plant
S
K line
According to a)
S
n1
According to b)
Booksize Power Units
Manual, (GH2), 04/2014, 6SL3097-4AC00-0BP6
Required rated power of the
isolating transformer /
autotransformer
S (1.27 • P )
n n
Required rated power of the
isolating transformer /
autotransformer
S (1.27 • P )
n n
≥ 26 kVA
≥ 51 kVA
≥ 127 kVA
.
= 50,000 kVA
= 16 kW • 70 • 0.73 = 820 kVA
= 1.27 • 16 kW = 21 kVA
> S ⇒ S is decisive.
n1 n2
= 50,000 kVA
= 16 kW • 70 • 0.73 = 820 kVA
= 1.27 • 16 kW = 21 kVA
Line connection and line-side power components
Required short-circuit
voltage U
k
Required short-circuit
voltage U
k
≤ 10 %
≤ 10 %
≤ 10 %
of 25 kVA for a short-circuit voltage u
n
3.11 Line connection variants
Minimum system fault level
required
S (70 • P )
Kline n
Minimum system fault level
required S (30 • P )
Kline n
≥ 0.6 MVA
≥ 1.2 MVA
≥ 3.0 MVA
K
k
145