6.4.4
Cavitation protection
Overview
Cavitation occurs when air bubbles are generated around the surface of the impeller, resulting
in pump damage, unexpected noise, and decreased flow or pressure of the pipe system. The
cavitation protection will generate a fault/warning when cavitation conditions are deemed to be
present. If the converter gets no feedback from the pump transducer, it will trip to prevent
cavitation damage. This function saves the maintenance efforts and extends the lifetime
expectancy of the system.
Function description
To use cavitation protection, a sensor is required to monitor the actual flow or pressure and
feedback value. You can use parameter p29625 to enable/disable cavitation protection:
● p29625 = 0: cavitation protection is disabled
● p29625 = 1: cavitation protection triggers fault F52960
● p29625 = 2: cavitation protection triggers warning A52961
To enable cavitation protetion, set p29625 = 1 or 2.
After you have enabled cavitation protection, the following preconditions should also be met to
activate cavitation protection:
● Cavitation protection threshold p29626 is set according to experience (The value is lower
than the normal actual flow or pressure).
p29626 is a percentage of feedback output for triggering a fault or warning. r2272 is the
scaled actual value of technology controller. For example, if the maximum range for the
pressure sensor is 20 mA/25 bar and the actual sensor value is 12 mA/12.5 bar, then r2272
is 50%. If r2272 < p29626, cavitation protection can be triggered after delay time p29627.
The range of delay time is 1 s to 65500 s.
● The technology controller has reached the minimum limit (status of r53.10 is 1) or the
maximum limit (status of r53.11 is 1).
● The converter operation is enabled (status of r52.2 is 1).
● The technology controller is enabled (p2200 = 1).
Advanced commissioning
6.4 Pump control
SINAMICS G120X converter
320
Operating Instructions, 06/2019, FW V1.01, A5E44751209B AC
