I have purchased a topsoil screen with a 3 phase electric motor OLI MVE 1700/15N-60AO the screen is 2

or even an alternative motor to replace the 3 phase for a 50amp 220V motor. and suggestions

So the question is that you want to power a 3-phase device with a single-phase generator?

That's not going to work. You need another device to convert the single-phase AC to 3-phase power.

The nameplate on the motor indicates that it is only 0.75 kW and only draws 2.16 amps. Why are you asking about a "... 50 amp 220 V" motor? Your 26 kW generator is huge relative to nameplate power on that motor, but so be it.

I will skip all that and operate on the ASSumption that you need to get your new 3-phase-motor-powered machine working (at its nameplate ratings) powered by that generator.



Your supply voltage (220V single phase) is of course wrong, so to use that 460 volt motor "as is" you will also need a 3-phase step-up transformer.

I have a funny feeling that there is no practical single-phase-motor retrofit for that machine, because that machine looks like its motor is integral to the vibration-generator. It's not a standard off-the-shelf motor driving a sprocket or pulley or anything of that sort. (It may contain bits and pieces of an off-the-shelf motor inside, but it sounds like tearing the motor apart in order to rebuild it as a single-phase motor is not what you want to do.)

Should have bought American.
An American motor would have been a 9 lead, 230/460 Volt motor rather than a 266/460 Volt motor.
You will need a VFD, Variable Frequency Drive.
This will take single phase in, rectify it to DC and then invert the DC to a Pulse Width Modulated three phase variable voltage and frequency.
There are a couple of ways to do this.
I suggest that you price out each option.
1. Use a 230 Volt single phase input VFD and step up the output with a 1:2 ratio three phase transformer to 460 Volts.
2. Use a 230/460 Volt transformer to step up the voltage to 460 Volts and then use an oversized VFD that will accept a single phase input. (Not all will).

1. Size the VFD to 2 1/2 times the motor KVA.
That motor is 1.721 KVA.
.75 kW is very misleading. It does not account for the poor efficiency and poor power factor, which must be supplied by the source.
And, by the way, 220 Volts as a standard voltage went out in the '50s.
Your generator is rated at 120/240 Volts. It is industry practice to use 460 Volt rated motors on 480 Volt supplies to allow for some line loss.
So, 1.721 x 2.5 = 4.3 KVA VFD output. If the VFD must be derated for use on single phase, that derating is in addition to the 2.5 factor.
The transformer: I would look for 120:240/240:480 Volt transformers, suitable for buck boost operation.
Wire the 120:240 in series for 240 Volts.
Wire the 240:480 in parallel for 240 Volts.
Connect the transformers as a wye connected auto-transformer to step up the output of the VFD.
Rating of the transformers; The transformers will have to supply the rated motor current at 240 Volts.
so, 2.16 Amps x 240 Volts = .518 KVA.
I would use the next available larger size, probably .75 KVA transformers.

2. Select a suitable VFD for use at 460/480 Volts.
Determine if it is suitable for use on single phase.
Derate the VFD if required.
When in doubt, use the next larger size.
Buy one 120:240/240:480 Volt transformer to step the 240 Volts single phase up to 480 Volts.
Wire the transformer as described above as an auto transformer.
Again size the transformer to handle the input current of the VFD at the 240 Volt rating.
I expect you will be at about 2 KVA, but do your own math please.

3. After you have priced out those options, go to a motor rewind shop and inquire as to the cost of having your motor rewound for 230 Volts three phase.
You will still need a suitable VFD.
The motor shop can advise you on a suitable VFD and also give you a complete turnkey job.

Bill
--------------------
"Why not the best?"
Jimmy Carter

If you want to go with a rotary phase convertor, figure on a 5 HP or 7.5 HP idler motor.
Also a pretty large transformer.

Bill
--------------------
"Why not the best?"
Jimmy Carter

I bought it online auction and was not shopping for one so I didn't get time to study it. I would rather replace it with an American made motor. I haven't been able to confidently fined an American compatible replacement motor. (three phase is new to me first time needing it)
any suggestions for an American made replacement motor.

I've been told that the Miller Bobcat 3 Phase Welder 907505 would run the motor. I'm[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1608363326/tips/MIL907505_704x704_qcsv9m.webp[/url][URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1608363638/tips/IMG_1716_phtxzm.webp[/url] looking for a plug and play option.

For a plug-and-play no-thinking-required solution - a 3-phase generator with enough capacity will do it.

Minor digging finds that you can buy a phase converter as well, but the cost of buying both a suitably sized phases converter and a suitably sized transformer is going to put you in the same ballpark as that generator.

That is not just a motor.
That is a motor based vibrator.
You won't find a standard motor to replace it and I doubt that you will find a single phase vibrator.
You may be able to make a belt drive vibrator.
A shaft, two pillow blocks and a pulley.
Drill cross holes in the shaft and install bolts with multiple nuts to create an unbalance.
Spin it with a 1/2 HP single phase motor.
There are others in these fora better qualified than me to suggest adequate construction details.
For safety, enclose the spinning weights in pieces of suitably sized pipe.
If money is no object or if you want an excuse to own a new Bobcat welder, yes, that Miller Bobcat should run the vibrator easily.
Bill
--------------------
"Why not the best?"
Jimmy Carter

By the way, when you get it running, it will probably work much better in one direction of rotation than in the other direction.

Bill
--------------------
"Why not the best?"
Jimmy Carter

This is a "Vibrator Motor" these units are tuned to the driven system. Your screening system will have a sprung support between the screen and the equipment frame. The point of the system is to set up resonant shaking so little of the vibration is lost to shaking the foundation, it should be spent shaking your product.

Changing the vibrator motor to something other than the one supplied could result in needing to re-tune the system. The suggestions that you find or scrounge a 3 phase power source is going to be much less aggravation than motor replacement.
Searching the internet I found a new 480 3phase 5 kW generator for $4,000 list price. That should provide a baseline for comparing other options.

what generator do you recommend?

What am I missing in that this thing uses:
3-phase
460V
68% PF (ugh!)
2.16A

How can that relate to 750W?

I get 1.17kW.

Keith Cress
kcress -

If this is all you want to run I'd get a 240V generator and 240 input 240 output VFD that's rated for 2HP. I'd set the VFD to put out 60Hz always and feed it's output in to a transformer to make 480V. Plug the sifter into the transformer's output.

I'd start the generator.
Let it warm up for a minute.
Close the breaker on to the VFD.
Hit the "RUN" button on the VFD.
Use the sifter.
Reverse the process to shutdown.

Get a Honda 5-6kW generator that outputs 240V single phase and let the VFD synthesize the 3 phase.
Make sure the VFD allows single phase input as waross mentioned.
Possible VFD Note specifically for 1ph 240V input
Possible Generator



Keith Cress
kcress -

Hi Keith.
I ran the same numbers and got 1.17 KVA with a poor power factor and poor efficiency.
The output limit of a generator is KVA but on small sets that is dumbed down to kW for the average homeowner.

Bill
--------------------
"Why not the best?"
Jimmy Carter

How good (I don't know) is the frequency regulation on these small generators?

How good does it need to be to make sure the vibrator hits resonance?

If the one doesn't live up to the other, that might be another argument in favour of the VFD.

A.

Given the change in resonance caused by varying loads of material, resonance is fairly forgiving.


Bill
--------------------
"Why not the best?"
Jimmy Carter

I don't think I've seen a 'small' three phase generator under about 40kW.

Keith Cress
kcress -

Hi Keith. You may have seen one and didn't realize it.
The largest single phase set that I have seen was 15 KVA.
20 KVA and above were typically three phase sets reconnected in double delta for single phase. (120:240 Volts)
At 3600 RPM the largest single phase set was 25 KVA.
There are exceptions.
BUT;
A 20 KVA set is still overkill for this installation.
It will come down to pricing.
Finding a good used major component at a low price will probably sway the final decision as to which solution to use.

Bill
--------------------
"Why not the best?"
Jimmy Carter

Good to know.
And, I suspect you're right about a major find paving the rest of the path though I can also see the OP simply cook-booking it.

Keith Cress
kcress -