Single phase to 3 phase the simple way

An explanation of the use of a single phase power source to operate one 3 phase motor to produce 3 phase power for another. By using a pilot motor to rotate a 3 phase motor then applying single phase power to the motor, 3 phase power will be produced to operate the 3 phase motor on your equipment. This the simplest and best way to operate 3 phase equipment on single phase. 3 phase motors are often available for a fairly low price due to their limited applications. A wiring schematic is included
If you are a homeowner looking to repair your own appliance, understand that the voltages can be lethal, the fuels are highly flammable and high pressures are used. Know your limits.

[joedell]

I’m building a converter now. I’m using a giant 10 hp electric motor I salvaged out of an old industrial Varian Vacuum pump. For my starter motor I’m using a large DC motor and speed controller salvaged out of an optical polishing machine. I also salvaged all of the switches, capacitors and breakers and relays from machinery that my company scrapped out due to age. I used such a big motor so i can drive multiple pieces of machinery in my shop. I’m going to run the output of my converter into a small sub panel in my shop which will then be hooked to all of my machines. I cant wait for it to be done. Been a lot of fun getting all of these different components to come together as a whole new machine.

[joeclement]

I really preciate you taking the time to create this very informative video!!! I know that a fairly large number of creators try to exhibit their higher learning techniques & abilities, Whe in actuality it's usually nutt'n more than fluff to fill the creator's short orchestrated dance hall production!!! Thanks again, Joe C.

[rickolson]

Brother, that is too cool. I can not thank you enough for what you are doing.
KEEP UP THE GREAT WORK....

[tylerpeterson]

Ive seen/heard of this a few times. For people not too savvy with electric motors I highly suggest buying a phase converter, pretty much does the same thing but can be professionally installed.

[Fireship]

Another excellent video! Years ago before you tube and online sources, I thought you had to purchase an expensive phase converter to be able to do exactly this. I passed up a nice 3ph compressor for cheap years ago that this setup probably would have run. Thanks for taking the time to make this and all your fantastic videos!

[sandystanley]

My father got himself 3 phase in his garage including a transformer to get from 208V to 600V. All for less than 3k while Hydro wanted 60k to bring it in.

[leeroyholloway]

Just got mine built & tested today. Works great!

[cliffmeima]

Good  job, it took me a few minutes to understand what you were doing, At first I did not understand why you did not include the wiring of the separate starter motor, but then I realized that including it would have been more confusing. Nice job as usual.

[electricalindustry]

Awesome video and project, one of those"why didn't I think of that" moments.

[Myles]

Good old school tech. Well done.
Handy for homeowners since 3 phase power isn't common to residential areas.



Old video, but comments bump up videos!

[grayfurnaceman]

The described method of converting single to 3 phase is a rotary phase converter. There are converters that use one of the 3 phase windings as a start winding and use a start cap to start the motor. Then it runs mostly on single phase.

[davidschwartz]

I take it that switching the direction of the driven motor direction is as usual change any two wires with connections with a switch? Thanks for the money-saving tip! Again!

[joemc]

I worked in a shop with 3 phase for 15 years. When we lost a leg, say a fuse went out, sometimes we left the motor run until we got the replacement. But if you shut it off then you all know that you can't restart it. 50 years in the trade and sill learning.

[grayfurnaceman]

True, however, the cut off switch is very accessible. Good point though. Thanks for the comment.
GFM

[grayfurnaceman]

I have a friend that repairs welder. He tells me that this will work ok if you don't use the generated phase on the control circuits. The voltage in this phase will not be high enough to operate the controls. Hope this helps.
GFM

[grayfurnaceman]

I have a friend that repairs welders and I asked him. They will work. I would not guarantee perfect operation. If you can wire it so the third phase is not used for the controls and is only used for the main transformer it works best. Also different brands work differently. Yeah I know about the safety issues. Hope this helps.
GFM

[ryanmalin]

361, 000 views and only 624 likes?! Ungrateful folks out there. Thanks for the content. I like to be the tech who knows what im doing. When i tell people about this method, they are blown away by how simple it is. Hope youre having a good weekend!

[grayfurnaceman]

That works by using a capacitor to the 3d winding, thus using the 3d winding as a start winding. When the motor starts, the winding is dropped out. The only time I ever tried that, i think the backfeed from the controlled motor blew out the capacitor. Not really sure why. This system is used because it is simple and pretty much bullet proof. Thanks for the comment.
GFM

[grayfurnaceman]

You will need a 3 phase motor of approximately one and one half times the hp of the motor you want to drive. A 1/4 to 1/2 hp start motor to start the larger motor. Belt and pulleys to drive the start the motor.

[summitDan]

could I run a 3 phase 2hp motor 220 volts horizontal bandsaw that has a smaller 0.5 horse water pump that turns on with a switch?