Delta 1.07 VFD-D D - Manual (Page 140)

Appendix B How to Select AC Motor Drive |DD Series
B-6
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.