Siemens SIRIUS 3RW30 - 12.5 Dimensioning of soft starters for motors with high starting current conditions

Configuration
12.4 Reducing the rated data
SIRIUS 3RW30 / 3RW40
Manual, 10/2018, NEB535199502000/RS-AB/005
93
12.4
Reducing the rated data
You can reduce the rated data of the SIRIUS 3RW30 and 3RW40 soft starters if
● The installation altitude is higher than 1000 m.
● The ambient temperature in the switching device's environment exceeds 40 °C.
● The lateral clearances described earlier are not complied with, e.g. side-by-side assembly
or direct mounting of other switching devices (assembly type).
● The vertical mounting position is not complied with.
12.5
Dimensioning of soft starters for motors with high starting current
conditions
When using motors with high starting current conditions (typically I/I
e
≥ 8), overdimensioning
of the 3RW40 soft starter can be necessary. For this application case, we recommend
3RW40 soft starters with product version E07 or higher (for 3RW40 sizes S0, S2, S3) or with
product version E11 or higher (for 3RW40 sizes S6 and S12). These 3RW40 devices make it
possible to select the set value for current limiting sufficiently high for a successful motor
start (refer to chapter Setting the current limiting value (Page 114)).
For dimensioning soft starters for motors with high starting current conditions (typically I/I
e
>
8), refer to Siemens Technical Assistance (Page 15).