Variable Speed Controls for Small AC Motors

Here is just a small sample from a recent request I had from a customer regarding variable frequency drives and motors. His original request involved looking for a single phase drive for his motor which was used to run a fan.

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Marshall Wolf Automation offers a complete line of high performance AC drives, soft starters and industrial electric motors.

Answer:

I can offer 115 volt single phase input 230 volt three phase output to 1.5 hp (this is without derating the drive)

I can offer 230 volt single phase input 230 volt three phase output to 5 hp (this is without derating the drive)

I can derate a drive to operate with a 230 volt three phase input but cannot derate a 115 volt single phase input drive. There is no way to develop 230 volt in a drive using 115 volt above 1.5 hp. I must have at least 230 single phase input to run a drive the normally operates at 230 volt three phase (6 hp minimum) and is rated for a 3 hp 230 volt three phase motor. I would double the hp rating of this drive to handle single phase in and three phase out.

With that said I would need to have a transformer to take the 115 volt single phase to 230 volt single phase. I would then set up the drive to take 230 volt single phase in and rated to handle the amperage for a 3hp motor.

SM250 AC Tech 5 hp variable frequency drive $316.80

http://www.wolfautomation.com/ProductList.aspx?query=sm250&Submit=Search

DS0034 Teco 3 hp 56 frame 230/460 three phase motor ODP $172.46

I am awaiting information on the transformer.

Question:

Would you be able to quote me a replacement motor that is 3 phase, and a VFD (variable frequency drive)? I would like to keep the cost down, but would it be possible to get a motor with 80% turn down?

Is there any reason not to run a 3 phase VFD with 120 single phase input and 230v three phase output?