Siemens SIRIUS 3RW30 Manual page 18

Product description
3.3 Functional principle of the SIRIUS 3RW30 and 3RW40 soft starters
Example
SIEMENS 1LG4253AA motor (55 kW)
Rated data at 400 V
P :
e
I :
e
I
direct starting
M :
e
n :
e
M
direct starting
Set starting voltage:
=> I
=> M
The diagrams below show the starting current and torque characteristics for a three-phase
induction motor in combination with a soft starter:
Figure 3-3
18
:
:
½ of direct starting current (approx. 350 A)
starting
¼ of direct starting torque (approx. 175 Nm)
starting
Reduced current characteristic of a three-phase induction motor during starting with a
SIRIUS 3RW30 or 3RW40 soft starter
55 kW
100 A
Approx. 700 A
355 Nm ; e.g.: M = 9.55 x 55 kW x
e
1480 rpm
Approx. 700 Nm
50 % (½ of mains voltage)
Manual, 01/2010, 535 1995-02 DS01
SIRIUS 3RW30 / 3RW40