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System Manual V2 – MOVITRAC® B
6
Motor selection
Project Planning
6.5
Motor selection
6.5.1
Basic recommendations
•
Only use motors with at least Thermal class F.
•
Use the TF thermistor or TH bimetallic switch.
•
Preferably use 4-pole motors. This applies particularly if you are operating
gearmotors with a high oil filling level because of their vertical mounting position. The
churning losses are very great with 2-pole motors.
6.5.2
Voltage-frequency characteristic curve
The asynchronous motor follows a load-dependent voltage/frequency characteristic in
V/f operating modes. The motor model is continuously calculated in the VFC operating
mode. At startup, set the characteristic curve with rated motor voltage and rated motor
frequency. The setting determines the speed-dependent torque and power characteris-
tics of the asynchronous motor.
The following figure shows an example of the voltage/frequency characteristic curves of
an asynchronous AC motor 230 / 400 V, 50 Hz.
The MOVITRAC
®
B output voltage is limited by the provided supply voltage.
6.5.3
Dynamic applications
For dynamic applications, you must have a drive with a rated inverter current greater
than the rated motor current.
Set the following parameters so the motor can generate at most 150 % of the rated
motor torque:
•
Current limit P303
•
Slip compensation P324
Increase these parameters manually by a factor of approx. 1.4 for dynamic applications.
1 Star connection; 400 V, 50 Hz
2 Delta connection 230 V / 50 Hz
3 Delta connection 400 V / 87 Hz
0
230
400
0
f [Hz]
50
87
1
3
2
U [V]
A
Содержание MOVITRAC MC07B0037-2A3-4-00
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