Delta Electronics VFD-VE Series manual Special motors, Pole-changing Dahlander motor, Motor torque

Appendix C How to Select the Right AC Motor Drive

„Resonant mechanical vibration: anti-vibration (damping) rubbers should be used to mount equipment that runs at varying speed.

„Motor imbalance: special care is required for operation at 50 or 60 Hz and higher frequency.

„To avoid resonances, use the Skip frequencies.

9.The motor fan will be very noisy when the motor speed exceeds 50 or 60Hz.

Special motors:

1.Pole-changing (Dahlander) motor:

The rated current is differs from that of a standard motor. Please check before operation and select the capacity of the AC motor drive carefully. When changing the pole number the motor needs to be stopped first. If over current occurs during operation or regenerative voltage is too high, please let the motor free run to stop (coast).

2.Submersible motor:

The rated current is higher than that of a standard motor. Please check before operation and choose the capacity of the AC motor drive carefully. With long motor cable between AC motor drive and motor, available motor torque is reduced.

3.Explosion-proof (Ex) motor:

Needs to be installed in a safe place and the wiring should comply with the (Ex) requirements. Delta AC Motor Drives are not suitable for (Ex) areas with special precautions.

4.Gear reduction motor:

The lubricating method of reduction gearbox and speed range for continuous operation will be different and depending on brand. The lubricating function for operating long time at low speed and for high-speed operation needs to be considered carefully.

5.Synchronous motor:

The rated current and starting current are higher than for standard motors. Please check before operation and choose the capacity of the AC motor drive carefully. When the AC motor drive operates more than one motor, please pay attention to starting and changing the motor.

Power Transmission Mechanism

Pay attention to reduced lubrication when operating gear reduction motors, gearboxes, belts and chains, etc. over longer periods at low speeds. At high speeds of 50/60Hz and above, lifetime reducing noises and vibrations may occur.

Motor torque

C-6 Revision August 2008, 03VE, SW V2.04