Baumuller b maXX BM1000 - How to Choose a Suitable Motor; Standard Motor

How to choose a suitable motor
Manual b maXX
®
BM1000
Document No. 5.07003.04 Baumüller Nürnberg GmbH
164
of 174
F.3
F.3 How to choose a suitable motor
F.3.1 Standard motor
When using the b maXX
®
drive to operate a standard 3-phase induction motor, take the follow-
ing precautions:
1 The energy loss is greater than for an inverter duty motor.
2 Avoid running motor at low speed for a long time. Under this condition, the motor temperature
may rise above the motor rating due to limited airflow produced by the motor's fan. Consider
external forced motor cooling.
3 When the standard motor operates at low speed for long time, the output load must be de-
creased.
4 The load tolerance of a standard motor is as follows:
Figure 77: Load duty-cycle
5 If 100 % continuous torque is required at low speed, it may be necessary to use a special in-
verter duty motor.
6 Motor dynamic balance and rotor endurance should be considered once the operating speed
exceeds the rated speed (60
Hz) of a standard motor.
7 Motor torque characteristics vary when an b maXX
®
drive instead of commercial power sup-
ply drives the motor. Check the load torque characteristics of the machine to be connected.
8 Because of the high carrier frequency PWM control of the b maXX
®
series, pay attention to
the following motor vibration problems:
m Resonant mechanical vibration: anti-vibration (damping) rubbers should be used to mount
equipment that runs at varying speed.
m Motor imbalance: special care is required for operation at 50 or 60 Hz and higher frequen-
cy.
m To avoid resonances, use the skip frequencies.
9 The motor fan will be very noisy when the motor speed exceeds 50 or 60Hz.