# 3 phase motor with single phase power



## Chuck Feathers (Aug 13, 2011)

I bought a used Powermatic Shaper. It's in a friends shop and I'm planning to rewire the 5hp 3 phase motor for use with single phase 220V power. I think it's an older model 26 but it may be a 2700. I want to be prepared when I get there. I've printed a pdf wiring schematic from the online manual. I've seen a few tutorials on Youtube using capacitors. Others say to just buy a single phase motor. I would appreciate any suggestions.


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## Steve Neul (Sep 2, 2011)

Chuck Feathers said:


> I bought a used Powermatic Shaper. It's in a friends shop and I'm planning to rewire the 5hp 3 phase motor for use with single phase 220V power. I think it's an older model 26 but it may be a 2700. I want to be prepared when I get there. I've printed a pdf wiring schematic from the online manual. I've seen a few tutorials on Youtube using capacitors. Others say to just buy a single phase motor. I would appreciate any suggestions.


It's a little more complex than that. What you are describing is a static phase converter. While it's true it will function you loose hp. I just don't know exactly how much but everyone I talked to when I bought a phase converter had bad things to say about them. What I ended up getting was a rotary phase converter. It's like the static phase converter except it has a motor attached to it. When two or more motors run off of a phase converter it generates closer to actual three phase power than the static model. The only problem is unless you use the saw often you end up having to turn the phase converter on and off as you use the saw. A cheaper and better solution would be a VFD, Variable Frequency Drive. It will convert single phase to three phase without having the second motor. 

Your easiest solution though if you thought would not be getting any more three phase equipment would be to replace the motor with a single phase model. In my case though I bought a machine which had a irreplaceable motor. Once I did get the phase converter though three phase just wasn't an issue whether to buy a machine or not. I have since bought a jointer, planer and a radial arm saw that were three phase since I bought the stroke sander.


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## Catpower (Jan 11, 2016)

You can also build a rotary phase converter, I have been running my Axleson engine lathe on one for about 25 years, all you need is a 3 phase motor twice as big as the motor you want to operate, hook Line one of the incoming power to L1 on the ballast motor,and L1 of the saws motor and hook Line 2 of the incoming power to L3 on the ballast motor and L3 of the saws motor, and hook L2 of the ballast motor to L2 of the saws motor. You can use a static converter to power up the ballast motor or do like I did and just get an old blower motor and pulleys so the blower motor spins the ballast motor, and as soon as it gets up to speed apply power, and Wa La you have 3 ph

You can find good used 3 phase motors at junk yards or if you know a mechanical contractor he would probably have some around or could look out for one, I am a mechanical contractor so the motors were a non issue with me. And they also say that 2 pole motor, 3450 RPM is better for a phase converted, but I have made them for friends out of 4 pole 1725 RPM motors and they have worked fine


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## epicfail48 (Mar 27, 2014)

Chuck Feathers said:


> I bought a used Powermatic Shaper. It's in a friends shop and I'm planning to rewire the 5hp 3 phase motor for use with single phase 220V power. I think it's an older model 26 but it may be a 2700. I want to be prepared when I get there. I've printed a pdf wiring schematic from the online manual. I've seen a few tutorials on Youtube using capacitors. Others say to just buy a single phase motor. I would appreciate any suggestions.


Here's a suggestion: don't mess with something that can kill you without knowing exactly what you're doing. You can't "rewire" a 3 phase motor to run on single phase, regardless of whether or not you have a wiring schematic, or what some guy on YouTube said he did with a capacitor. 

You have a couple, workable options. You could get a static phase converter, but that would limit your 5 hp motor to about 3hp, you could get a rotary phase converter, which would give the motor on the shaper full power but be rather inefficient to run, or you could wire in a vfd to the motor. However, all of those options would require either hiring an electrician or having a very, very good working knowledge of electricity and wiring in general. 

Probably easiest just to find a single phase motor you can replace yours with


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## Chuck Feathers (Aug 13, 2011)

A cheaper and better solution would be a VFD said:


> Thanks.:smile: I'll go out and get the amp output and the speed info. As I'm reading about VFD's, I will need that information. The HP is not as important.


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## Catpower (Jan 11, 2016)

The only problem is the small VFDs are only rated for about 3 hp, but check the amp draw on the motor, you might be able to squeak by on the amp rating, and it would also give you a lot more speed control. You might want to look at the insulation rating on the motor also, with heavy use, it needs to be a F rated insulation on the windings. The rating will be on the data plate


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## Chuck Feathers (Aug 13, 2011)

Catpower said:


> The only problem is the small VFDs are only rated for about 3 hp, but check the amp draw on the motor


Yes, most of what I found was limited to 3hp except for this exception: 
http://www.gohz.com/5hp-vfd. Does this look ok? This may be the best way to go since I will not have to deal with motor mounts or switch replacement.


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## Steve Neul (Sep 2, 2011)

I've never had a VFD but have always heard you should get a larger VFD than the motor, just the same as you would if you got a rotary phase converter. Better check into it before buying.


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## Catpower (Jan 11, 2016)

Chuck Feathers said:


> Yes, most of what I found was limited to 3hp except for this exception:
> http://www.gohz.com/5hp-vfd. Does this look ok? This may be the best way to go since I will not have to deal with motor mounts or switch replacement.



Yes that would work, just make sure the motor's amp rating isn't over the drives rating, sometimes the fudge the figures on some stuff, I have never heard of this brand but there is a lot of stuff I have never heard of

There is no need to over size the VFD, actually you can cause some problems by over sizing

The cool part about the drive is you can make most of them over speed the motor and it won't hurt it, some will go to 120 hertz so a 3450 RPM motor will run 6900 RPM, or you can go super slow but I don't think you would ever need that on a shaper LOL

But just for the info, you never want to run a motor on a VFD lower than 20 hertz, for long periods it will cause damage to the bearings from transient voltage


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## Chuck Feathers (Aug 13, 2011)

I have to wait until Tues when my contractor friend gets back in town. My first career was building and my second was teaching. I'm retired now. Instead of selling all my shop tools and Graco sprayer, I let my contractor friend use them since he has a 10,000 sq foot shop.


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## Quickstep (Apr 10, 2012)

I put a VFD on my lathe to make the 3 phase motor run on single phase. I get almost infinitely variable speed and reverse. But, it loses torque at low speed. Sometimes wish I'd just have gotten a new motor.


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## Catpower (Jan 11, 2016)

Quickstep said:


> I put a VFD on my lathe to make the 3 phase motor run on single phase. I get almost infinitely variable speed and reverse. But, it loses torque at low speed. Sometimes wish I'd just have gotten a new motor.


You really don't want to run them at a speed lower than 20 Hz, they can create a transient voltage that can ruin the bearings unless the shaft is grounded by an Aegis or similar device, it grounds the shaft to the motor frame to dissipate the stray power, if it doesn't have the devise it will ground the rotor through the bearings and pits them


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## Chuck Feathers (Aug 13, 2011)

Catpower said:


> Yes that would work, just make sure the motor's amp rating isn't over the drives rating, sometimes the fudge the figures on some stuff


I discovered it's a Powermatic 27 5HP, 3450RPM Baldour, 13-12/5 Amps, and Hz is 53.

I sent a message to GoHz.com to confirm the http://www.gohz.com/5hp-vfd will work and I asked for any wiring assistance. I have some wiring and electronics so I'm not afraid of wiring.


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## Catpower (Jan 11, 2016)

Chuck Feathers said:


> I discovered it's a Powermatic 27 5HP, 3450RPM Baldour, 13-12/5 Amps, and Hz is 53.
> 
> I sent a message to GoHz.com to confirm the http://www.gohz.com/5hp-vfd will work and I asked for any wiring assistance. I have some wiring and electronics so I'm not afraid of wiring.



Looks like you are good to go

If you are manually controlling it they are a snap to wire, but if you mix in some automation, sometimes there is some confusion between English and the country of origins language conversion that can leave you wondering


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## Chuck Feathers (Aug 13, 2011)

I ordered the http://www.gohz.com/5hp-vfd. They also responded to my questions and gave me a wiring diagram for my motor. This was the only vfd I could find that would convert 1PH power to 3PH for a 5hp motor.:smile:


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## Minnesota Marty (Feb 27, 2015)

Chuck, 
Your solution intrigues me. I am looking at a 5hp 3 phase Powermatic 2000 table saw. It is priced right so working out the 3 phase dilemma would be helpful to me. Let us know how things work out. 

Good Luck with the project. 

Marty


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## WarnerConstInc. (Nov 25, 2008)

For single phase in and 3 phase out on a VFD, you need one rated twice as big as your FLA. They can usually be had fairly inexpensively on that big auction site.

Unless you buy one that is specifically for single phase input. most only work with 3hp, a few will go up to 5.


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## Chuck Feathers (Aug 13, 2011)

WarnerConstInc. said:


> For single phase in and 3 phase out on a VFD, you need one rated twice as big as your FLA. They can usually be had fairly inexpensively on that big auction site.
> 
> Unless you buy one that is specifically for single phase input. most only work with 3hp, a few will go up to 5.


You have me a little concerned. The VFD I ordered (http://www.gohz.com/5hp-vfd) says it is rated for 1PH to 3PH at 5hp. I looked up some FLA charts and they say for 1PH 5hp the FLA is 28. Do you see a problem with the VFD I ordered?:blink:


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## Steve Neul (Sep 2, 2011)

Chuck Feathers said:


> You have me a little concerned. The VFD I ordered (http://www.gohz.com/5hp-vfd) says it is rated for 1PH to 3PH at 5hp. I looked up some FLA charts and they say for 1PH 5hp the FLA is 28. Do you see a problem with the VFD I ordered?:blink:


Warner doesn't stop by very often and may not see your post. He said the same thing I've always heard about sizing a VFD. You might want to read this, especially "Voltage". http://www.vfds.com/blog/vfd-buying-guide


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## WarnerConstInc. (Nov 25, 2008)

That one is designed for single phase input and to run the 5hp.

The whole derating thing becomes advantageous when you have the desire to be thrifty.

Used vfd's can be had pretty cheap.


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## Catpower (Jan 11, 2016)

Chuck Feathers said:


> You have me a little concerned. The VFD I ordered (http://www.gohz.com/5hp-vfd) says it is rated for 1PH to 3PH at 5hp. I looked up some FLA charts and they say for 1PH 5hp the FLA is 28. Do you see a problem with the VFD I ordered?:blink:


No there is no problem, the drive you ordered is withing the limits of the amp draw of the motor, so it will work out fine. I don't know where they get the order the next size up, because it is just a waste of money. I have been working on VFD's since they made them, the first ones used vacuum tubes for the diodes, they were pretty easy to work on, just take all the tubes out and go to Revco Drugstore and they had a kiosk with a tube tester. LOL The drives have come a long way in the past 20 years, the 5 ph drive you ordered 20 years ago would have been the size of a small refrigerator, and probably cost $10,000

The main problem you can run into though is some of the motors don't have good enough insulation on the windings, but unless you are hammering it hard that generally isn't a problem, but if you ever need to replace the motor, find one with F rated insulation on the windings


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## Chuck Feathers (Aug 13, 2011)

Steve Neul said:


> Warner doesn't stop by very often and may not see your post. He said the same thing I've always heard about sizing a VFD. You might want to read this, especially "Voltage". http://www.vfds.com/blog/vfd-buying-guide


I went to your link, which is also a seller. Here is one they sell with the same specs of what I bought but more than twice the cost: http://www.vfds.com/5hp-230v-hitachi-


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## Steve Neul (Sep 2, 2011)

Chuck Feathers said:


> I went to your link, which is also a seller. Here is one they sell with the same specs of what I bought but more than twice the cost: http://www.vfds.com/5hp-230v-hitachi-


I really can't argue the point on VFD's. I found out about them after I got a rotary phase converter to do three phase for me. I do though trust Warner's judgement. He buys a lot of three phase equipment and if he says buy one twice what the motor is rated at I would do it. 

In my case the first three phase machine I bought was a stroke sander which had a motor that wasn't replaceable. At first I was going to replace the motor with one single phase. After getting the phase converter, three phase wasn't an issue anymore. You can really get some nice old machinery cheep just because they are old and three phase. What most folks don't understand is the old machinery if taken care of just don't break down like the new machines do. They were built at a time when the quality of the product was job one.


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## WarnerConstInc. (Nov 25, 2008)

There are one's rated for single phase input and 3 phase output.

One's that are rated as 3 phase only are the ones you need to over size by a factor of 1.73. 

It is easier to just say look for one that is twice the size you need (by amps)


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## Chuck Feathers (Aug 13, 2011)

WarnerConstInc. said:


> There are one's rated for single phase input and 3 phase output.
> 
> One's that are rated as 3 phase only are the ones you need to over size by a factor of 1.73.
> )


If it's rated as 3 phase only, how can you connect 220V single phase to it?


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## Chuck Feathers (Aug 13, 2011)

I just did some research and answered my own question. Here is a link that explains what Warner has been saying. I was surprised to discover that you can use a 3PH only VFD with a 1PH input by derating it. This link should be read by all: http://www.dartcontrols.com/wp-content/uploads/2012/01/De-Rating-VFD-for-Single-Phase-Power.pdf


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## Catpower (Jan 11, 2016)

Y'all are making something relatively simple too hard. When they rate the drive by HP the 1.73 factor is already figured in. Now if you buy one solely by the data plate figures, you would need to figure in the 1.73, because of inrush amp draw like for reversing. The 3 phase motor will put out a little less power, because the third leg is being generated, but unless you are really working the motor hard you will never notice. But if you are working the motor hard, you will end up with a ruined motor unless it has the properly rated insulation

A VFD just rectifies the a/c current into DC current and it is a pulsating DC current that allows for the variable frequency.If it were possible I would show you on an O scope. I have been in the HVAC industry for about 40 years, and we use and spec VFDs daily from miniature drives to thousands of horse power drives, it isn't rocket science

I am not trying to argue with anyone, just trying to make it as economically priced as possible(We don't like to use the word cheap LOL) and have it work right, but if you want to spend more it is up to you


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## Chuck Feathers (Aug 13, 2011)

Catpower said:


> Y'all are making something relatively simple too hard. When they rate the drive by HP the 1.73 factor is already figured in. Now if you buy one solely by the data plate figures, you would need to figure in the 1.73, because of inrush amp draw like for reversing. The 3 phase motor will put out a little less power, because the third leg is being generated, but unless you are really working the motor hard you will never notice. But if you are working the motor hard, you will end up with a ruined motor unless it has the properly rated insulation
> 
> A VFD just rectifies the a/c current into DC current and it is a pulsating DC current that allows for the variable frequency.If it were possible I would show you on an O scope. I have been in the HVAC industry for about 40 years, and we use and spec VFDs daily from miniature drives to thousands of horse power drives, it isn't rocket science
> 
> I am not trying to argue with anyone, just trying to make it as economically priced as possible(We don't like to use the word cheap LOL) and have it work right, but if you want to spend more it is up to you


Thanks again for an intelligent answer. I will hook up my $270 vfd and save the money. It's possible that some have always gone the derating route and all they use for larger motors. It's true that there are not many vfd's that use a 220V 1PH input for 5HP motors. Almost all 1PH input versions stop at 3HP. I enjoy saving money.:shifty:


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## Catpower (Jan 11, 2016)

I was glad to see you found one too, as 3 hp has been the cut off for a long time

Today we just got done setting up my new toy, a Grizzly 22x42 lathe, and I noticed it has a 3 hp motor and a 3 hp VFD. I know it is Chinese, but it is the 4th machine I have gotten from them and I have really been impressed, everything else I have is pre 70 Rockwell/Delta, but I refuse to pay the high prices for an American named company to built them in china

I would gladly pay more for American made, but that is also the reason I won't buy a DeWalt, a few years back I thought I needed a chopsaw, I had a bunch of tubing to cut, and figured it would be faster than one of my bandsaws (I was wrong LOL) but I paid $100 more for the DeWalt, with an identical Chinese made one next to it, but it had made in America all over it, and it had it on the box, when I got to the shop and opened it it was made in china, it ticked me off


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## Chuck Feathers (Aug 13, 2011)

*it works*

It's been a long time but I want to update this thread. To make the vfd with 220V single phase input and three phase output for a 5hp motor I had to by-pass the Powermatic magnetic starter and the Furness reverse switch. UVW of the VFD connects directly to the motor. I'll take some pics and continue later.


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## Chuck Feathers (Aug 13, 2011)

*Update with photos*

I'm attaching pics to give better information. Powermatic 27 5hp 3 phase shaper. I removed all the wiring to the Magnetic starter and the Furness reverse switch. I connected the 3 phase output from UVW of the VFD directly to the motor. The single phase 220V leads went to R&S of the VFD. Ground goes to the end on the right side. When I first connected white to U, red to V and black to W I had a reading of 48hz. After I switched white and black wires, it read 23hz. Today I switched the white and black wire back to the first position but I still get 23hz? The jog knob increases the speed.

The VFD requires a filtered box with an exhaust fan near the top to keep dust out of the electronics. 

I plan to add a Co-Matic DC40 to the shaper. If you want to run a 5hp three phase machine with single phase power, this does the trick.


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## Chuck Feathers (Aug 13, 2011)

I have added new updates at the end of this thread


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