Vacon Plc
Phone:
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Fax: +358-(0)201 212 205
Service:
+358-40-8371 150
E-mail: [email protected]
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Vacon
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Multi-purpose Control Application II
Multi-purpose Control Application II
Multi-purpose Control Application II
Multi-purpose Control Application II
Multi-purpose Control Application II
This default setting should be used if there is no special need
This default setting should be used if there is no special need
This default setting should be used if there is no special need
This default setting should be used if there is no special need
This default setting should be used if there is no special need
for another setting.
for another setting.
for another setting.
for another setting.
for another setting.
Squared:
The voltage of the motor changes following a squared curve form
1
1
1
1
1
with the frequency in the area from 0 Hz to the field weakening
point (par. 6
.....
3) where the nominal voltage is also supplied to
the motor. See figure 5-2.
The motor runs undermagnetised below the field weakening point
and produces less torque and electromechanical noise. Squared
U/f ratio can be used in applications where torque demand of
the load is proportional to the square of the speed, e.g. in centrifugal
fans and pumps.
Un
(Par 6. 4)
(Par. 6. 3)
U[V]
f[Hz]
UD012K07
Default: Nominal
voltage of the motor
Linear
Squared
Field weakening
point
Default: Nominal
frequency of the
motor
Figure 5-2 Linear and squared U/f curves.
Programm. The U/f curve can be programmed with three different points.
U/f curve
The parameters for programming are explained in chapter 5.2.
2
2
2
2
2
Programmable U/f curve can be used if the other settings do not
satisfy the needs of the application. See figure 5-3.
Un
Par 6. 4
Par. 6. 3
U[V]
f[Hz]
UD012K08
Par. 6. 5
(Def. 5 Hz)
Par. 6. 6
(Def. 10%)
Par. 6. 7
(Def. 1.3%)
Default: Nominal
voltage of the motor
Field weakening
point
Default: Nominal
frequency of the
motor
Figure 5-3 Programmable U/f curve.
1.9 U/f optimisation
1.9 U/f optimisation
1.9 U/f optimisation
1.9 U/f optimisation
1.9 U/f optimisation
Automatic
The voltage to the motor changes automatically which makes the
torque
motor produce sufficient torque to start and run at low frequencies. The
boost
voltage increase depends on the motor type and power.
Automatic torque boost can be used in applications where starting
torque due to starting friction is high, e.g. in conveyors.
