Siemens 3RW44 Manual page 130

Device functions
7.3 Coasting methods
Pump stop
In pump applications, so-called water hammers can occur if the drive is stopped abruptly
without using pump stop. Water hammers are caused by the sudden stall and the
accompanying pressure deviations in the pump. They cause noise and mechanical impacts
on the piping system, as well as on any flaps and valves installed there.
Figure 7-7
Typical applications for soft stop/pump stop
Use soft stop/pump stop
● in pumps to prevent water hammer.
● in conveyor belts to prevent the conveyed materials from toppling.
130
Soft stop/pump stop
CAUTION
Risk of property damage
For optimum motor protection, use the combination of electronic motor overload
protection and evaluation of a temperature sensor installed in the motor.
Manual, 03/2017, NEB535219502000/RS-AB/008
3RW44 soft starters