6.17.4
Skip frequency bands and minimum speed
Skip frequency bands
The inverter has four skip frequency bands that prevent continuous motor operation within a
specific speed range. Further information is provided in function diagram 3050 of the List
Manual.
Overview of the manuals (Page 459)
Minimum speed
The inverter prevents continuous motor operation at speeds < minimum speed.
0LQLPXP
VSHHG
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W
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0$;
S
Speeds where the absolute value is less than the minimum speed are only possible during
motor operation when accelerating or braking.
Table 6-42
Setting the minimum speed
Parameter
Description
p1080
Minimum speed (factory setting: 0 rpm)
p1106
CI: Minimum speed signal source (factory setting: 0)
Dynamic specification of the minimum speed
NOTICE
Incorrect direction of motor rotation if the parameterization is not suitable
If you are using an analog input as speed setpoint source, then for a setpoint = 0 V, noise
voltages can be superimposed on the analog input signal. After the on command, the motor
accelerates up to the minimum frequency in the direction of the random polarity of the noise
voltage. A motor rotating in the wrong direction can cause significant material damage to the
machine or system.
● Inhibit the motor direction of rotation that is not permissible.
Advanced commissioning
6.17 Setpoint calculation
SINAMICS G120C converter
246
Operating Instructions, 09/2017, FW V4.7 SP9, A5E34263257B AF
