Selecting The U/F Characteristic - Siemens Sinamics G110M Operating Instructions Manual

The value of the output voltage at the rated motor frequency also depends on the following
variables:
● Ratio between the inverter size and the motor size
● Line voltage
● Line impedance
● Actual motor torque
The maximum possible output voltage as a function of the input voltage is provided in the
technical data.
6.17.1.2

Selecting the U/f characteristic

Table 6- 39 Linear and parabolic characteristics
Requirement Application examples
The required Conveyor belts, roller
torque is inde- conveyors, chain con-
pendent of the veyors, eccentric worm
speed pumps, compressors,
extruders, centrifuges,
agitators, mixers
The required Centrifugal pumps,
torque increases radial fans, axial fans
with the speed
Table 6- 40 Characteristics for special applications
Requirement
Applications with a low
dynamic response and
constant speed
The inverter must maintain
the motor speed constant
for the longest possible
time.
Distributed converter for SIMOGEAR geared motors
Operating Instructions, 09/2017, FW V4.7.9, A5E31298649B AH
Technical data (Page 339)
Remark
-
The inverter equalizes the voltage drops across
the stator resistance. Recommended for motors
less than 7.5 kW.
Precondition: You have set the motor data ac-
cording to the rating plate and have performed
the motor identification after quick commission-
ing.
Lower losses in the motor and inverter than for a
linear characteristic.
Application Remark
examples
Centrifugal If the speed setpoint is reached, and remains
pumps, radial unchanged for 5 seconds, then the inverter
fans, axial reduces is output voltage.
fans
As a consequence, the ECO mode saves
energy with respect to the parabolic charac-
teristic.
Drives in the When reaching the maximum current limit,
textile sector the inverter only reduces the output voltage,
but not the frequency.
Advanced commissioning
6.17 Motor control
Characteris- Parameter
tic
Linear p1300 = 0
Linear with p1300 = 1
Flux Current
Control
(FCC)
Parabolic p1300 = 2
Characteristic Parameter
ECO mode p1300 = 4
or
p1300 = 7
Precise fre- p1300 = 5
quency char- or
acteristic p1300 = 6
235