Functions 
  5.1 Start modes 
SIRIUS 3RW30 / 3RW40 
Manual, 10/2018, NEB535199502000/RS-AB/005 
39 
Ramp-up detection (3RW40 only)  
The SIRIUS 3RW40 soft starter is equipped with an integrated ramp-up detection function. If 
it detects a motor startup, the motor voltage is immediately increased to 100% of the mains 
voltage. The internal bypass contacts close and the thyristors are bridged.  
 
Figure 5-4  Current limiting with soft starter 
Typical applications for current limiting  
Current limiting is used for applications with large centrifugal masses (mass inertias) and 
therefore longer starting times, e.g. fans, circular saws etc.