Protection Of The Soft Starter Against Short-Circuits (Type Of Assignment 2) - Siemens 3RW44 Manual

Installation, connection and feeder configuration

4.3 Protection of the soft starter against short-circuits (type of assignment 2)

4.3 Protection of the soft starter against short-circuits (type of
assignment 2)
The soft starter has internal protection to prevent overloading of the thyristors. This internal
thyristor protection function is not sufficient in the event of a defect in the motor windings or a
short-circuit in the motor's power supply cable, for example. Special semiconductor fuses,
e.g. SITOR fuses from SIEMENS, must be used for this purpose.
Figure 4-7
40
Block diagram of a feeder with semiconductor fuses
Manual, 03/2017, NEB535219502000/RS-AB/008
3RW44 soft starters