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I have several 3HP 3 phase motors I have collected over the years. Can I just drive one of them with a single phase 220 volt controller? Then use the generated 3 phase current to run any three phase equipment I want to?

I remember a local guy had one he had made. If I remember right he had a blue controller similar to https://www.valinonline.com/products/esv222n02yxb . Could even be the exact one.

I am thinking to just wall mount this unit and run some wiring and plugs through the shop to anything that is 3 phase.

So tell how crazy I am. LOL

I'm basically trying to validate my path.
 

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I have several 3HP 3 phase motors I have collected over the years. Can I just drive one of them with a single phase 220 volt controller? Then use the generated 3 phase current to run any three phase equipment I want to?

I remember a local guy had one he had made. If I remember right he had a blue controller similar to https://www.valinonline.com/products/esv222n02yxb . Could even be the exact one.

I am thinking to just wall mount this unit and run some wiring and plugs through the shop to anything that is 3 phase.

So tell how crazy I am. LOL

I'm basically trying to validate my path.
The link is a VFD. That is a great way to run small 3 phase motors on single phase. I’m confused by this statement: “Then use the generated 3 phase current to run any three phase equipment I want to?”. Could you clarify?
 

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I have several 3HP 3 phase motors I have collected over the years. Can I just drive one of them with a single phase 220 volt controller? Then use the generated 3 phase current to run any three phase equipment I want to?

I am thinking to just wall mount this unit and run some wiring and plugs through the shop to anything that is 3 phase.

So tell how crazy I am. LOL

I'm basically trying to validate my path.
You can and it will be a rotary phase converter. You would need to add capacitors and a contactor to start it and I think to keep the voltages regular. A three phase motor will run on 2 phase but it won’t start. I have heard you can hook it to 2 phase and pull start it and then use it as a converter but I have never tried that and don’t know if it is true. I am sure you can search the Internet and find instructions in how to do it.

I have a 5hp and a 20hp from here.Rotary, Static Electrical Supply - North America Phase Converter Company Yeah I know that’s cheating but it works great.
 

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I think the OP might be talking about 2 things...a rotary phase converter and a VFD. Are you thinking that you need both? Or are you wondering which one would be best? I prefer VFDs for things in the 3hp or less range. They produce a better sine wave and are more efficient, and you get the variable speed functionality.
 

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You don’t actually have 2 phases unless you have a very rare and old electrical installation in some cities. I’ve only seen it once and the system was very weird and had some peculiarities that I haven’t quite wrapped my head around. They require a special transformer and I would assume a large capacitor bank to get three phase equipment to work.

Anyway, you can get a 3 phase motor to run on single phase and then use the unused 3rd leg of the motor to power downstream 3 phase motors. It’s very crude and inefficient at best. Due to the sine waves not being 120 apart, the timing of the motor is off. This creates a lot of imbalance and heat. Because if this, you want a very robust motor to use for your rotary converter. If you want to use a 5 hp motor in your lathe, you need at least a 7.5, preferably a 10hp motor. The current will be less and the bigger motor will handle the heat generated by the phase shift and inefficiencies of this method.

Basically put, you wire in leg A to T1 of your motor, leg B to T2, and then T1, T2, & T3 now become your “hot leads” for anything downstream. As mentioned, it won’t self start. I’ve seen an old brake rotor used as a flywheel and was handy to “kickstart” the motor. Lots of groaning and a slow start will result. Gobs of current will be used as this happens. So you’ll need a larger breaker than normal and larger wire to boot. Go at least 2 sizes larger.

The better method is getting a rotary converter panel that will provide starting capacitors and a running capacitor. It will have a start/stop buttons on the front and make wiring/installation easier and more engineered. It will also start the motor quicker with much less current draw and provide a lot better 3 phase output. It’s not perfect, but light years ahead of the crude setup I described previously.

The best method is a VFD or a soft start capable of single phase to 3 phase operation.

You’ll be much much further ahead to use a VFD. So much more efficient, quieter, and no idling motor laying around in the shop. Yes, more bucks up front, but well worth it. Plus you’ll have the ability to change the speed of your motor. :good2:
 

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You don’t actually have 2 phases unless you have a very rare and old electrical installation in some cities.
Thank you sir. Not sure what I was typing. Meant single phase 220v. Thought 2 hots, typed 2 phase.:banghead: I am too proud to go back and edit it. You know the French yogurt and all.:laugh:
 

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Its a common mistake, but worth correcting in a conversation like this one. :drinks: Not trying to be the “Correction Police.” :laugh:
 

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I have a Variable Frequency Drive that powers a Delta Radial Arm Saw with a 3 phase motor. It has soft start and I believe braking plus speed control. It works beautifully and doesn't need the 3 phase motor controller. It's just wired direct to the switch on the saw. Cost was less than 200 bucks and is good for 3 hp or below.

Ron
 

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VFD's for anything under a 3hp motor is the way to go, they are simple, cost effective, and offer variable speed and reversing. I have three in my shop, on the lathe, mill and belt grinder.
 

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I run my entire woodshop on 2 15kw rotary phase converters. I believe they are Ronk. They feed a 3 phase panel. I usually just start 1 and that covers most of what I run every day. I need to start the second one when I run my Weinig molder and dust system. The largest motor on the molder is 15hp and with all motors including the dust system there is a total of 45.5 hp running at the same time.

Just remember the generated leg will be much higher voltage than the other 2 so if you have sensitive electronics on the machine do not hook them to that leg

You can make one from a 3 phase motor but I only had good luck with very old motors, not newer ones. I just threw some run capacitors in the mix and started it spinning with a small 110 motor with a belt and pully and flipped the switch

As far as sizing is concerned, the motor you use needs to be at least as big as your largest motor you need to run and will run a total of 3 time that at the same time.
example would be you have a 10 hp motor to run, you would need to use a 10 hp as the converter but could run a total of 30 hp of smaller sizes at the same time. Each motor in the loop adds to system so to speak. They do run hot but usually when they don't have a load on them. Under a load they don't run any warmer than a normal motor would. They also become more efficient the more you load them up. I use to know all the numbers when I was setting mine up but that was 12 yrs ago and forgot most of it
 
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