Lenze L-force 8400 BaseLine D - Page 77

Firmware 03.00 - DMS EN 5.0 - 07/2009 L 77
8400 BaseLine D | Software Manual
Motor control (MCTRL)
Selection of the operating mode
Setting the V/f base frequency
The V/f base frequency determines the slope of the V/f characteristic and has considerable
influence on the current, torque, and power performance of the motor.
– The setting in code C015
applies to all permissible mains voltages.
– Mains fluctuations or fluctuations of the DC-bus voltage (operation in generator
mode) do not need to be considered when the code is set. They are automatically
compensated by the internal mains voltage compensation of the device.
– Depending on the setting of C015
it may be necessary to adapt the reference speed
C011
to be able to run through the whole motor speed range.
– The V/f base frequency is automatically calculated from the data stored in the motor
nameplate by the motor parameter identification:
Typical values for the V/f base frequency C015
:
•V
frequency inverter
:
–Frequency inverter 400 V
–Frequency inverter 230 V
•V
ratedmot
: Rated motor voltage depending on the
connection method
•f
rated
: Rated motor frequency
Frequency inverter 400 V Frequency inverter 230 V
Motor
voltage [V]
Motor
frequency
[Hz]
Motor
connection
C015 Motor
voltage [V]
Motor
frequency
[Hz]
Motor
connection
C015
230 / 400 50  50 Hz 230 50  50 Hz
220 / 380 50  52.6 Hz 220 / 380 50  52.3 Hz
280 / 480 60  50 Hz
400 / 690
400
50
50
 50 Hz
230 / 400
280 / 480
400
50
60
87
 87 Hz
220 / 380 50  90.9 Hz
 Note!
4-pole asynchronous motors, which are designed for a rated frequency of f = 50
Hz in star connection, can be operated in delta connection when being
constantly excited up to f = 87 Hz.
• Advantages:
– Higher speed-setting range
– 73% higher power output in case of standard motors
• Motor current and motor power increase by the factor .
• The field weakening range starts above 87 Hz.
• Generally, this process can also be used with motors which have different
numbers of pole pairs. In case of 2-pole asynchronous motors, the mechanical
limit speed must be maintained.
C00015 Hz[]
U
freq inv,
V[]
U
ratedmot
V[]
---------------------------------- -
f
rated
Hz[]⋅=
3