Stop Modes; Stop Without Load (3Rw30 And 3Rw40) - Siemens SIRIUS 3RW30 Manual

Functions

5.2 Stop modes

5.2 Stop modes
You can choose between different stop modes reflecting the wide range of applications for
SIRIUS soft starters. The motor stop can be optimally adapted to each particular application.
If a start command is issued during the stop process, the process is interrupted and the
motor is started again with the set start mode.
Note
If you select "soft stop" (3RW40 only) as the stop mode, the feeder (soft starter, cables,
feeder protective devices, and motor) may need to be dimensioned for higher values
because the current exceeds the rated motor current during the stop process.
5.2.1

Stop without load (3RW30 and 3RW40)

"Stop without load" means the power supplied to the motor via the soft starter is interrupted
when the ON command is removed from the starter. The motor coasts to a standstill, driven
only by the mass inertia (centrifugal mass) of the rotor and load. This is also referred to as a
natural stop. A large centrifugal mass means a longer stop time without load.
Typical applications for stop without load
Stop without load is used for loads that place no special demands on the startup
characteristic, e.g. fans.
40
SIRIUS 3RW30 / 3RW40
Manual, 10/2018, NEB535199502000/RS-AB/005