VFD question dealing with Hz

You could also put a transformer between the VFD and motor to step up from 230 to 575V. More cost and another device in the system, but probably (slightly) cheaper than a motor. So long as your VFD can handle the motor's kVA (volts*amps) it should work.
 
You could also put a transformer between the VFD and motor to step up from 230 to 575V. More cost and another device in the system, but probably (slightly) cheaper than a motor. So long as your VFD can handle the motor's kVA (volts*amps) it should work.
The VFD can't handle that much voltage. I will get a new motor and try and Craigslist this motor.
 
The VFD would only see its 230V max, the transformer and motor would be the only things to see the 575...3 phase 208 to 575 transformers are available. The VFD can output sufficient power (volt amps, VA), just not at high enough voltage to push max amps though the motor windings. Voila instant derating of HP in the motor. You trade volts for amps via a transformer. It WILL work, but MAY NOT be the cheapest alternative. Choose a 3 phase 208/230V to 575 transformer of the same or larger kVA as the VFD/motor, wire the output of the VFD to the line/input of the transformer, and wire the motor to the output/.load side of the transformer. This happens in my world (petrochemical instrument/electrical) all the time as 480V generators are widely available but when we have to power down a 2400V or 4160V motor control center and keep a pump running, we have to put a transformer between the 480V generator and the 4160 pump motor. Transformers don't care about frequency so long as there is some (they don't work on DC) as they pass frequency straight through. Again, it will work, but might not be the cheapest alternative. Shop around and see...
 
I wouldn't go the transformer route- It works in theory but it's less efficient and usually too costly. And they weigh a ton.
You should be OK using the 575 till you get another motor
Mark
 
From what I have heard VFDs and transformers on the output side don't play well together. Better to install a motor with the correct voltage then life will be good. :)
 
So what is inside the motor that requires the 575 volts? Why is it working on 220v? I've used the lathe several times, but haven't hogged anything yet? I'm guessing under a heavy load, it will bog down?
 
The windings, it's built for that voltage, no way to change it. Its running but probably at less than half power. Get the motor you posted, it should work fine.
 
Jim, transformers on the output side of VFDs can get tricky but are commonly done. For a 2 Hp motor likely the only issue would be limits on how low of speed it could be run. Most of what I (and industry in general) see are hundreds (thousands) of Hp motors for pumps and such. Harmonics, load balancing, impedence matching, etc. become issues fast in this world and that is probably the source of the 'don't do it' conventional wisdom. If the OP has easy access (like they did the motor) to such a transformer, it is worth a shot. If they have to buy one new, a new motor makes more sense. I just offer an alternative to pursue if it makes sense to the particular application...a new motor is certainly a very good option here, as is a different VFD that will take multiple input V and output 575V 3 phase.
 
Curious... What is your single phase voltage to the VFD? The plate on the motor says 3ph 575volt. Do you have it wired via the DELTA or STAR connections in the motor's junction box?
Also, what brand are those green link belts on your lathe?
Again on the belts...they work well. Although they are Harbor Freight, I believe they are made in the USA.
 
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