5 Motor control & motor settings
5.14 Parameterising the V/f characteristic control
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Lenze · i700 servo inverter · reference manual · DMS 3.0 EN · 06/2016 · TD06
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Parameterisable functions
Optionally the following functions can be activated for the V/f characteristic control:
• "DC-injection braking" function
• "Flying restart" function
In the Lenze setting these two functions are deactivated.
5.14.1 Defining the V/f characteristic shape
For purposes of adaption to different load profiles, the shape of the characteristic can be selected:
0x2B00 | 0x3300 - VFC: V/f characteristic - shape
[5-11] Principle of a linear V/f characteristic (on the left) and a quadratic V/f characteristic (on the right)
Selection list (Lenze setting printed in bold) Info
0 Linear (standard) Linear characteristic for drives with constant load torque
over the speed.
1 Square-law (pumps and fans) Square-law characteristic for drives with a linear or
square-law load torque over the speed.
• Square-law V/f characteristics are preferably used for
centrifugal pumps and fan drives.
• Please always check whether the corresponding drive
is suitable for operation with a quadratic V/f
characteristic!
• If your pump drive or fan drive is not suitable for
operation with a square-law V/f characteristic, use
the linear V/f characteristic instead, or select the
servo control.
2 User-defined User-definable V/f characteristic for drives requiring an
adaptation of the magnetising current via the output
speed.
• The user-definable V/f characteristic can for instance
be used for operation on special machines like the
reluctance motor, for the suppression of oscillations
on the machine, or for energy optimisation.
Write access CINH OSC P RX TX UNSIGNED_8
0
0
0
0
f
set
VV
f
set
Frequency at ref. point
0x2B01:2 | 0x3301:2
Voltage at ref. point
0xB01:1 | 0x3301:1
Voltage at ref. point
0x2B01:1 | 0x3301:1
Frequency at ref. point
0x2B01:2 | 0x3301:2