Inverter Rated Motor (VFD or VVVF Motor)
Machine Tools and Process industries do need variable speed motors to either achieve desired machine function or for energy conservation. Application like fan and certrifugal pumps are an excellent example of energy saving through VFD. VFD or Frequency Inverter is not a new word for the industry now. "mototek" Inverted rated motors are suitable to operate with VFDs.
The motors are insulated to withstand the voltage spikes generated while working with VFDs.
Depending upon the required operating speed range and close loop feed back for automation motors can be selected.
(A) Where speed of the motor is to be reduced approximately up to 50% of the rated speed, than the integral fan on the motor shaft is sufficient to provide enough cooling. It again depends on the type of load. If the load is of fan or centrifugal pump type, than motor with integral fan can go even further low speed at the same type heavy duty load with intermittent increasing load application may need extra cooling. This is just a guideline to understand the basic requirement of cooling.
(B) Where the speed of the motor is to be reduced further the integral fan mounted on the motor shaft becomes inactive OR when the speed of the motor is to be increased with a frequency above 60 Hz. The integral fan overloads the motor. ln such situation, it becomes very important to provide extra cooling by separately energized fan i.e. servo ventilation (lC 46 cooling). Servo ventilation (lC 46 cooling) is available from the frame 71 to 280. For smaller frames, it is recommended to use higher frame, if B5 flange mounting than reduced flange can also be used.
(C) The automation requirements are increasing day by day and it is becoming important to control the speed of the motor or position of the motor shaft for positioning and synchronizing requirement of machine tools and process. "mototek" motors with servo ventilation as well as normal fan cooled are available with either incremental encoders, absolute encoders and resolvers of various supply and output. As a standard "mototek" can offer quick delivery with 1024 PPR - 10 to 30V DC Push- Pull incremental encoders.
Servo ventilated motors, motors with encoders or both are longer compared to standard motors. If the space is the craitaria, please confirm the length before ordering.
