Functions Under "Additional Parameters - Siemens SIRIUS 3RW51 Equipment Manual

Operating principle of Soft torque during stopping
The Soft Torque function enables the motor to coast down smoothly at an almost constant rate
of deceleration. Ensuring that the motor coasts down smoothly is particularly useful for
stopping pumps in order to prevent water hammers in the connected piping. The Soft Torque
function for stopping can only be activated when a stopping time of more than 3 seconds is set.
Speed curve
n
N
①
②
8.7

Functions under "Additional parameters"

Operating principle
The 3RW51 soft starter has additional functions and settable parameters that are to be found
under "Additional parameters" in the 3RW5 HMI High Feature.
Setting options
• 3RW5 HMI High Feature (accessory)
Access protection to 3RW5 HMI High Feature is not active or has been reset.
Menu: "Parameters > Soft Starter > Additional parameters"
• You can find additional setting options, if they exist, in the associated chapter of the
respective parameter.
SIRIUS 3RW51 Soft Starter
Equipment Manual, 09/2020, A5E37108631002A/RS-AC/003
Rated motor speed
Motor speed with Soft Torque
Motor speed without Soft Torque
8.7 Functions under "Additional parameters"
Functions
99