Three Ways To Run A Three Phase Motor On Single Phase, And the Pro's and Con's of Each Method  

For the person just learning. Needing a grasp to understand. This guy is it. He is far more advanced than the learning person needs. Yet talks to us like we are people. So humble. He is why RU-vid was invented. To teach and help. Very smart man. Love the videos.

I’m a Journeyman Electrician and I’ve got to say watching your videos has taught me more than any class I ever took. Your videos are so informative yet so interesting. Awesome content.

you have a great electrical mind. the video you made with your kids makes your father skills 10x the electric skills. Genius

wish i had met someone like you when i was younger, I tried to understand this stuff over the years, and now at 70 yrs old I am starting to understand it when you explain it. You are so cool. thanks.

Jeremy, you are a perfect example of the American pride of excellence through independent investigation. Revealing one's own potential through learning and then giving it on to others by teaching is you by example. I love this channel. 72 years old and still learning here. And you - I would like to meet you someday - are the teacher I wish I had had when I was 12 years old! Thanks for your fine example and your channel content. Impressed I am!

I rarely comment on any how-to video, but I felt compelled to tell you what a great job you do with these. I have watched several, and the quality is consistently very high. You have the ability to convey complex ideas in a very straightforward way. Thank you.

Great work! I love the effort and time you put into this. The fact that you covered such a multifaceted concept in so many different ways, in a DIY project, is incredible. Taking the time to share it all afterwards is just above and beyond. Thank you!

you Sir are the MR Rogers of electrical engineering, people can learn a lot from your vids!

Jeremy, I've been watching your vids for some time, and you just keep getting better and better. Reckon you would have made a great science and tech teacher. Many thanks.

Thanks for this explanation on how you can do this, I’d always heard “ it can’t be done “ but you proved it can be done. Thanks again !!

Love your channel. I'm a machinist and I've really been interested in building my own shop. Give everything character. It's nice to see a video of someone I can understand. Learned a lot watching. Much appreciated.

you are by far the best teacher of this electrical stuff ever. been trying to grasp this stuff for years. your giant 3 phase brain is able to convert this knowledge into little spoonfuls of single phase knowledge which my muddy brain actually comprehends. thank you sir and kindest regards from Massachusetts!! 🇺🇸

This is a lot of information. Good to see you show the "not so good" options along with good options.

Jerremy, I would like to suggest a fourth method. You can start a three phase motor on 220/240. Wire up two legs and then literally pull start the motor like you would a lawn mower. It does not have the full horsepower but I have seen it work. Once the first one is started you can then run other motors and start them like you would with the pony motor. I don't know if it heated up as much as the run capacitor method and you obviously need a way to disconnect the load but it will work. I was told that with multiple ones around the shop the person who did it was eventually able to basically run each one on just a single phase input since he had some sort of a switch in place to switch the second phase from the line to a third pony motor. Honestly using a capacitor start method you should also be able to momentarily use a cap to start and then remove the cap and keep the other phases connected and keep it running with those phases balanced and the third generating. The person also told me that he was able to actually fool the power meter into spinning backwards with his single phase input method... I don't know if it was true or not but the power company came out to his place as per his story due to discrepancies and pulled the meter with things running to see if he had splice power in before the meter and was stealing electricity. The story went on that it all died when the meter was pulled and so the assumption was that the meter was being spun backwards because it was not able to read things correctly due to the noise the motor systems were backfeeding into the meter. He said he would leave everything running for weeks on end. They said they could put in a different meter that would be able to catch it but that the power companies cost to do so would be so large it would end up being a huge loss for them to do so vs his ability to just shave his bill down to 50 bucks a month vs 100. Again I can not say this is true or not but I saw with my own eyes a three phase motor start and run with the pull start method.

Excellent teacher. Clear and concise. Speaks in a language I can understand even though I am not good with electrical work.

Just recently discovered your channel and am really enjoying your videos. I am a civil engineer, whom was required to take several circuits courses in my program with little practical application. Many years later I have taken up a woodworking hobby and have been performing maintenance on previously owned electrical motors. I share a similar you enthusiasm for the centrifugal start cap switch, its brilliant in it's simplicity and just goes to show how the simplest solutions are often the best.

Your a genius at your skills. No one was ever able to explain the capacitors providing a extra phase like you did. Im an electrician and have maintained a 3 phase motor running on single phase through capacitors providing the 3rd phase. The motor amps were never balanced with a load. The motor held out fine for many years. This was way before variable frequency drives were available and small enough to power small pumps. Thank you . You are very entertaining and knowledgeable.

Always remember when working with a VFD that it has a capacitor bank that stores a DC charge and could take a few minutes to drain down to safe levels after removing power. Check the DC terminals for voltage before touching the terminals or opening the drive. Thanks for the video Jeremy, I am a VFD repair tech guy. Love your videos.

So happy I came across your channel man so very informative you don’t just GIVE out answers either you need to think a bit which makes the viewer that much smarter. I’ve been binging your motor and wiring videos and can’t thank you enough for taking the time to explain and share your passion and knowledge with others. And if it means anything else very proud to see you include your entire family and include them in the learning and projects. Thank you again. Jeff, Chicago IL

I just bought an older Singer industrial sewing machine 281-22 that came with a 3 phase motor. Most people who own these go with the 110v servo motor to run them. I decided it was a good time to learn how to convert single phase to 3 phase then get the 110v servo later if needed. I really enjoyed your video and appreciate your help with all I learned from you. I am going to keep an eye out for more of your videos. Thank you from Bremerton Washington

As always, a wonderful video. I've done a lot of my own electrical work in my business and in my personal shop. I am now reviewing what I've learned because I am moving from the US to Sweden and I am learning how to transfer all of my US knowledge to the Swedish system. What is very interesting about Sweden is that they have 3 phase, 50 hertz power to nearly every home, farm and industrial site. The only exceptions are to some of the very old, remote houses that were farms that were electrified in the day when electricity was only used for light bulbs so that you could save on the use of candles in the winter. Your videos are a great help in coming up with modifications and workarounds to getting my shop in Sweden into functional shape. Again thanks for your great work. Having 3 phase nearly everywhere in Sweden makes it very nice for wiring a building because the wire gauge is so small relative to what we have in the US. My biggest problem is having 50 years worth of high quality electrical tools that I want to take to Sweden with me. I would get a dime on the dollar for my tools if I sold them here and then bought everything new in Sweden. I am coming up with creative ways to create 120 volt, 60 hz power in Sweden and running separate circuits to run my small tools on throughout the shop. On all of my large equipment I am simply going to sell the 60 hz motors here and repower with the equivalent 3 phase motors there. There is a really good electric motor shop in the small city near me that is willing to work with me on my repower needs. I am finding that there is an abundance of inexpensive 3 phase motors in Sweden. Also, my few pieces of 3 phase, 60 hz equipment can be run on the Swedisn 3 phase, 50 hz power understanding that they may run a bit slower or have less power.

Your a natural educator! I wish I would have been able to see these videos while in college. Makes a lot more sense now!!

Sir you are by far one of the BEST teachers with such clarity as a simple minded person such as myself can and does understand. You have helped me more than you will ever know. Do not stop sharing your knowledge, please! God Bless

I don't know you and I have never met you but your humility oozes from just your speech. And they say, "Intelligence breeds humility".

Very cool. I've watched "HUNDREDS" of videos on this subject, and founds yours the most informative and easy to follow. I will definitely stay tuned. Thanks alot.

I don't think I have ever seen a better video than this one on RU-vid or even elsewhere. Thank you very much for this helpful topic, and thank god for providing a knowledge angel as you!

Jeremy, great video. Over 30 years ago, a very talented mechanical guy, showed me a way to run two 3-phase motors from single phase without capacitors, just the wiring and a short piece of rope. About 15 years ago I passed this information to several electrical apprentices in our factory, and added a problem for them. Design a PLC program to replace the rope. What fun!! (For me, not so much for them).

i will highly recommend this channel to all my friends that tinker with motors and tools. You, sir are a master, bravo!

Ive been trying to get into this for a while.....watched loads of other vids.....but this series has been brilliant...thanks loads!!

Currently building a 2x72 belt grinder from scratch and this has been invaluable. I am good with lots of stuff but electrical things are just usually beyond my scope. I have watched a few of your videos now and the way you explain things using both technical terms and layman language is just incredible. Thank you for your time in putting these types of videos together.

I enjoy your channel. I consider myself a tinker/experimenter. I get this from my dad and he’s why I’m writing. He converted single phase to three phase by using a “dummy” three phase motor in between. He had a 220v single phase panel that he ran three wires from and, the best I remember, connected those wires to the dummy motors’ leads and on to the working three phase motor. Three sets of two connected, each pair separate. In order for this to produce the desired results, he would spin the shaft of the dummy motor by kick starting a pulley that was on the dummy. He did the spinning movement as he turned a separate three phase disconnect to the on position. All this was to power an older industrial metal lathe. There would be times when the lathe would stop working and the starting process would have to be redone. I hope you understand all that took place as it was fascinating for me to see this actually work. Keep up the good videos. Steve

Dude. You are the best. Your fanboying over that potential relay cracked me up. Thank you.

Great vid. I built my own roto phase for my shop back in '88. 1hp. 3ph. for the starter 300 mf of running cap. this powered a 5 hp 3ph as the main roto conv. and I ran a 10 hp compressor a 1.5 hp mill and a 5 hp. 3ph lathe.all simultaneously. I ran it for about 5 years. I got the wiring diagram from a Audell engineering book from the '30s and had the system checked by a friend who was an Electrical engineer at a large plant in Tn.

Jeremy: Great Vid as usual, another "cheap" option not covered is to use a 110V motor to spin up a 220 3 phase pony motor and then turn the 220 on the spinning motor. Output for third leg is created (cleaned up with Capacitor if desired) and the 110V motor is turned off...the 220 3 phase is then running on 220 1phase, creating a third leg for another motor in the shop. I've used one like this without a 110V starting motor by rolling the pulley on the 5hp 220 3ph motor over with my foot, then hitting 220 single ph power, it runs my 2.5hp 3ph mill motor. Risk is if power went out while using I may forget to kill the system, so I should add a Magnetic switch to the start switch which would turn itself off if the grid power died. Building a larger 20hp3PH I will drive off a 110 belt pulley for start as I have a 7hp Cincinnati mill I picked up. Great Vids, keep it up.

I have found your videos better than instructional sessions I had in college on these subjects, when studying for my electromechanical degree. Truly superior.

Wow ..very educational .. learned more watching this video then I have in 32 years of hands on Thanks!

I service PowerFlex VFD's for a living. I have been watching your videos a long time. This one made my day to see what I work on within your channel. R-S gives you 120V fan power generally. R-T does not give you 120V fan power. In your case it wont matter because your fans are 24V I think.

buddy if you are not an expert there are no experts, you have the most helpful and applicable videos that i have found so far. great work and thanks for the help.

I just fabricated a 60hp 220acv 3ph 1780rpm roto phase for my machine shop. Fabricated a frame that bolts on top of the 60 hp motor then a 2hp 220acv 1780rpm is mounted to that frame. Pulleys on each motor are 6 inch diameter double Grove B Belt. I then start the 2HP pony motor to operating rpm, I use a spring loaded on and off switch for this operation when I release pressure on this toggle switch it returns to off position. When the 2 motors are at the 1780 rpm I then energize power to the 60 hp through a magnetic start switch. The 60 hp continues to run on 220 and producing the third Phantom leg= 3 phase power. Because there is no power going to the 2hp pup motor now it just spins along with the 60 hp motor. I don't balance the line voltages on the 60 hp but balance the voltages on the load motors at each machine with run capacitors with 15 ph being the highest. The beauty about getting the 60 hp up to speed before you apply power is there is very little voltage draw on the circuit. While the motor is running at no load the amp draw is about 27/28 then obviously goes up under load.I have made numerous units with this approach for other people and myself and they have operated for years and years with no problems, the only thing I do check depending how hard I work the load motors are the run capacitors because they will loose there efficiency. Anyways I thought I would share this with you. But thanks for your great and informative video.

Another fine video. I put a 3 phase motor and VFD on my lathe to gain variable speed. It's worked out ok for me. I appreciate you teaching me a bit more on how it all works.

I had a similar situation a couple years ago. Went thru all you have so very well described here. My problem involved a 3 ph 480 vfd that I wanted to run on 240 1ph I had to purchase a voltage rated vfd to complete my project. You sorted it much quicker than I did. You are very well spoken in electrical knowledge.

Great video, Jeremy! I'm an electrical engineer, and love tinkering with things just like this. I have a 3-ph motor I have been meaning to integrate into my shop, and you've motivated me to get started. I might add that one source of potential relays is [probably older] salvaged HVAC units.

I built a rotary phase converter for my shop 15 years ago still works great this is really good information sir

nice stuff, smart teacher , good way to teaching ,very clear and accurate , no body is better than you here on RU-vid ,you are the men, i know because this was my job before

What a brilliant video. Someone who actually openly shares knowledge. Thank you for sharing.

We use single to three phase VFDs all the time (running commercial kitchen exhaust fans) for our customers. It's amazing the number of electricians that don't believe us when we tell them you can run a three-phase motor with single phase power with one of these. We primarily use Lenze ACTech VFDs for our lower budget, low horsepower systems (Usually 1-2HP motors). The DCKV system we sell (automated exhaust/make-up air fan control), we use Allen Bradley or ABB and primarily three phase inputs. It's amazing how many options these VFDs have and what they can do. I know we barely scratch the surface.

Worked for over 20 years with an aerospace company, we were small, family owned and designed our own products for mostly military aircraft. What was common in military but not civilian was the wire color on 3phase 400hz motors. Military was Black, Red and Green, A B C phases respectively while civilian was Blue, Red and White. Not sure if I have the right order for civilian but those were the colors for the phases. Just thought I would mention this in relation to what you had said concerning the green wire. Awesome tutorial, thanks.

Thank you for the video ! Years ago I had found someone that told me 15 microfarads per horsepower was good, at least for a test. I ran a 1.5 Marathon 208-240/460 volt 3phase motor on single phase, wired for 208/240 with a 30 mfd capacitor and it ran smooth, ran cool for over an hour, no load of course but it was kinda cool to see it come to life. ... I always wanted a VFD but at the time,. it wasn't an option due to funds. If I end up running into more 3 phase motors, a VFD will be the route I go.

Mechanical engineer here, wow your videos are incredible. They give me the confidence to tackle induction motors myself and not just rely on my electrical sub-contractor. No longer will induction motors and VFDs be "black boxes"

Automatic "Thumbs up" before I started watching... You are Awesome Sir! THANKS!

⚒🛠🔧⚙️Super informative, glad to be part of your cobbling for fun network. I really think you’er such a wizard and gifted in your knowledge and presentation, and ability to explain in an entertaining and informative way. Thanks for the effort, hard work and personal time invested, its a true valued service you provide. 🍺🍺🍺🍺🍺

You sir are a gentleman and an electrical scholar. Thank you for your videos, they are greatly appreciated!

At 5:47- Looks at giant capacitor on workbench. Grabs safety glasses! Thanks lol!

Bing your videos. You're a great teacher. So easy to listen to and understand no matter the listeners knowledge level

@Jeremy Fielding Jeremy,. As I read the first 10 or so comments, I'm amazed at how much your subscribers enjoy your videos and take the time to give you props and good energy... The LEAST YOU could do is take a few seconds to say, THANK YOU. Also,. You're making a VERY COMFORTABLE living$$ doing this work.. Hire someone to respond to subscribers, after all, it's us that are forced to listen to all your sponsor ads, etc. Thank you for probably not reading this. Thanks for your knowledge and videos.

There are not very many dedicated and well-experienced yet practical teachers like you. I loved every sec of this video. Well explained, demonstrated, and excellent commentary with great tips and knowledge. I liked your video and subscribed to your channel. Thank you for sharing your knowledge.

I run a home built seven HP rotary phase converter to power the three phase machines in my wood shop. I use the push button startup signal to provide the start capacitance and latch the run relay. The start cap is only connected while the button is held. The e-stop or loss of power disconnects the system. The more motors that are added to the load, the smoother the system runs.

Brilliant teacher, explaining in an easy to understand way. This video has helped me, so I thank you for sharing your knowledge.

Hello mate. I’m enjoying every post you do. I love the idea of utilising what I have collected in my shed. I’m a full creature when it comes to electrics and often need to relearn it when I need to do something.

I'm an industrial electrician and haven't heard of a potential relay until today. Neat device! Industrially the common practice is VFD's or soft starts. One thing I want to point out to your audience (maybe you said it and I missed it) is that rotary phase converters are a more efficient way of generating that third phase than VFD's. The NEC also states that the circuit load handling capability be 250% of the total amp draw for using rotary phase converters. On a 20A breaker 2HP is approaching that limit on a 240V line. Use the formula [(Volts x Amps)/746]/2.5 = NEC compliant HP motor rating. Explanation VxA = Watts, there are 746 watts in 1hp, divide by 2.5 (250%) to get the limit. The Voltage and Amp numbers come from main line voltage (in the US 120 or 240 depending on how it's wired) and the amp rating of the circuit based on the breaker size and wire gauge. If you're new to this I highly recommend getting a Ugly's Reference and learning to use it. Great resource to have. Great video! Love your channel. My explanation of things wasn't for you btw, just to help your watchers. I don't think you need it ;^)

What a lucid description of 3-Phase motors. Well done.

Thank you for your videos! I've learned so much from them. Easy to follow and not full of unneeded info to confuse. Keep up the good work...

Great explanation. I have always wondered how to run a 3ph from single without a converter or VFD. Thanks for showing us how to tinker in this video as well as your many others. You are a great educator, thank you for what you do.

Excellent discussion on a topic that confuses many home shop folks . Thanks .

Jeremy I don't know my elbow from a hole in the ground when it comes to this stuff but about three years ago I bought a Clausing Colchester lathe at an auction. I had a VFD on it that was 3 phase to 3 phase 440 10hp only. Since I have the typical North American residential 220 single. So I was looking at spending a bunch of money on a smaller motor and a different VFD. I talked to a local electric motor repair guy I've dealt with before and he told me to go over to a local industrial surplus outfit and get a 220/440 transformer and a 7hp 220/440 motor and use the existing VFD and just run my 220 through the transformer and run the resulting 440 single to the input on the VFD and the 3 phase220/440 output to the 7 Hp220/ 440 motor wired 440. The end of this whole rant is it works a treat. Since then I've wired tow or three 3 phase input VFDs with 220 input and they work fine but you need a VFD that's like 1.6% larger than the HP rating of the motor you are using.

Thank you sir from Gold Coast Australia. You just saved me a packet as i was thinking the capacitor was for me. Now its VDF all the way. Next time you are down under let me buy you a beer.

Jeremy, I've watched multiple videos of yours now. They are great, you are great, this is all great. Honestly thanks for helping get good information out to the people. Repurpose, reuse, recycle!! 🤑

Boy your to good with all this stuff, and here I'm just looking to run a 2 HP motor for my 2" belt sander, and trying to figure out what VFD I need. and help would be grand. I'm sure you know much more than I do. Great video,

I love these motor videos. I'm making a big collection of my own. In fact, I got a 10 amp vacuum motor today. Epic stuff Jeremy.

Love these educational videos, been a fan for a year or two now, as I don't have much mech eng background in my university training. Just a note of warning that should be highlighted somewhere (which I haven't yet noticed): In Australia it is completely illegal for any person to touch electrical AC mains wiring or open up any AC mains powered equipment unless is a fully qualified and licensed electrician. The fines are massive, well into the tens of thousands of dollars for individuals and an order of magnitude greater for companies. I am unsure of the status of other countries internationally, but it is certainly not the same here as in the USA, legislatively. Keep up the good work. Love to see your children participating in the educational journey, too.

Jeremy thx for taking the time to show several ways to run a 3 ph motor. My only beef with VFDs are that they feed a high frequency switching waveform to the windings. For the short term no worries. However, for the long term, unless a motor is rated for direct VFD connection, that high frequency switching waveform will cause insulation breakdown in the windings. The cure is a filter. When you price out the filters they cost several times what the VFD costs. How ironic. Just a few caps and coils and boom big bucks. I think it's because they have a captive audience. Oh well. Again thx for making this video.

You are a remarkable, wonderful youtube presenter. You quickly get right into it. You explain everything very clearly once, with no hemming and hawing, and you have an experimental home craftsman orientation. You deserve lots of credit. Three phase motors can be either Y wound or delta wound. If my memory is correct, Y wound is much better for generating a third leg. Using a 3 phase motor as an idler to generate a third phase is probably about 70-80% efficient or effective. A bigger idler might be more efficient electrically, but less mechanically Electronic phase generator are probably 80-90% efficient. The disadvantages are that you generally need to size the generator to the motor, and you generally can run only one motor per generator at a time, and they can be very noisy or spiky electronically. Variable frequency 3 phase could be handy in some situations. You can buy a properly designed rotophase generator. Looks like a motor case with no shafts sticking out and a big box attached to the side of several capacitors. Advertisers claim 90-95% efficiency. There are remote oil well pumps which use a rotophase converter as a cheaper alternative than running a third wire for the pump motor’s third phase. You can run several 3 phase motors simultaneously from the one rotophase generator. If the motors are not all under full load simultaneously, they can help each other. I have four or five 3 phase tools connect to a single 3 hp rotophase converter, including a 5 hp metal lathe. Have not managed to bog the lathe down even with a half inch depth of cut. I am not a motor engineer. If I were to make a wild guess, I would add maybe 10% more turns to the 2nd leg and maybe 30-40% more turns to the otherwise weak generated 3rd leg. I might try shifting the 3rd leg towards the 2nd leg for better induction coupling and balance that with bigger capacitors to the 1st leg. Inductors cause current to lag the voltage, and capacitors cause current to lead the voltage. I did have a metal can capacitor blow out on a high speed centrifugal fan once. Unfortunately, it burned out the windings before it, the capacitor blew.

Fantastic explanation. This is how I run my milling machine.

Great Video! The way you explained the starting relay was perfect.

Best description of all the options I’ve ever seen. I’ll definitely be checking out your other videos.

You are mostly correct. I have been running a shop made rotary converter for over 35 years and have made several. First in the U.S. we use split phase power that means that we have 2 legs of 3 phase delivered to your home and the phase angle is 120 deg not 180 deg. This supplies 2 of your 3 legs to a 3 phase motor so you get 2/3 not 1/3 of the name plate rating. The balance caps will bring up the 3rd leg along with back EMF to full line voltage. VFDs were not "a thing" when I first started running 3 phase motors on 2 phase power. For one motor sure they work well. But for the cost of a VFD, I would rather make a rotary converter as 3 phase equipment is much less expensive on the used market because all the home shop guys think they need to replace the motor.. which they don''t. Once you have the converter you can build your shop for much less cost and with higher quality equipment than a weekend warrior can with single phase equipment. Just another thought for the mixing pot.

I work with these things for a living so I'm always skeptical of 'youtube experts' who post videos like this. That said, this guy does a really good job of presenting the basics to help a beginner familiarize themselves with VFDs. Real good job. By the way, Automation Direct (and probably others) make a line of very affordable VFDs that will run a 1/2hp 3ph motor on single phase. Just watch your amperage draw.

Great video, I've been waiting for a video like this for a while.. thank you for taking the time to post it . 👍👌🏽

Keep in mind that when using a potential relay, as current through the relay starts to rise, it's not a bad idea to use the relay to trigger the coil on a contactor, and allow the high current side of the contactor to make and break the load. When the contacts in a potential relay weld themselves shut, all the smoke leaks out of the start capacitors.

This was very helpful. I was trying to figure out how to get power to a 3 phase plasma cutter, and a VFD is definitely what that would need. Thanks!

Wow this beginning part had me on edge as you turned the Toshiba drive off, but when you picked up the KB I thought it was on as the display was up. I’m sure that’s an edit thing. 23 amps is to large for your test equipment (plug top and bits). Heat and volt drop will lower your results. But I know you know that. I never knew you could do this. I have 33 years experience in the trade. This awesome, so glad I found this channel.

Hey thanks so much for posting such a comprehensive video explaining these things! It is by far the best I have seen. I have an old 35mm projector attached to a lamp console that each run on 220v 3 phase. I’m probably going to scrap the lamp house because it is too impractical and would consume massive amounts of energy. I definitely either wanted to either reconfigure (not an option) or replace the motor but they are hard to find. I’m on the prowl for a VFD now. Thanks again for the post!!

Very well explained and technically accurate. My only additional comment would be that reading motor amps on the three phases allows you to adjust the amount of capacitors to get nearly equal currents on all three phases (correct for that one particular loading condition) and thereby achieve cooler motor operation.

Wow I kinda understood . Thank u so much, best, yet I've subscribed.

That is a great video for the layperson. One more method, sort of a modification of your rotary phase converter, is to use a single phase motor to drive the three phase motor (which now acts as a generator). The two motors would be on the same shaft or connected by a belt and pulleys. The horse power of the single phase motor isn't important. The three phase motor acts as a rotary transformer, again, you aren't going to get the full horse power but it is simple and works. Reversing the direction of the single phase motor changes the phase sequence of the output. Once I did this but the single phase motor was defective and wouldn't start by itself, so I just gave it a spin by wrapping a rope around the shaft, or in my case, with my foot giving one of the pulleys a kick to cause it spin in the right direction. I've seen another method used, a common relay used in conjunction with a capacitor. The relay momentary puts the capacitor in the circuit as a start capacitor then the relay drops out, don't recall what they used for the time delay, but the potential relay solves that problem. Speaking of the potential relay, on your diagram you show the contact in the potential relay as a normally open, it should be symbolized as a normally closed. I changed my motors to single phase, but would love to have some VFD's. I can tell, you speak from experience, again, great job! - Jim

Just found your videos! Thank you for these helpful instructions.

He is the gift that keeps giving !!

Great explanation of phase conversion.

Nice job laying all this out. You sounded like a kid on Christmas morning finding out about potential relays. Potential relays used for bringing in a start capacitor were commonly used on hermetic refrigeration compressors for years. Your refrigerator should have one.

I have an Arco rotophase converter I bought in the 1980's, it is a 5/15, meaning it will turn single phase 220 into 3 phase enough to start a motor up to 5 horsepower and run up to 15 horsepower worth of motors simultaneously... it has been a reliable unit for my home shop...

I like your soomed picture bubble with detales of the rating plate on the engine, or electrical component you are introducing. Fantastic job with editing the video, and keep doing that. 👌🏼😇👍🏼

The treadmill motor was a good find!. I love recycling washers and dryers, and printers/copy machines are loaded with good mechanical parts. Another source you might have overlooked are burned out cfl bulbs and burned out GFI receptacles. They each have 5 1n4007 diodes good for 1,000v at 1 amp

Thank you very much for this wonderful video. I feel less stupid now!

Great video Jeremy, very informative, keep up the great work.

God bless you man, I've learnt a lot from you. Thanks for sharing..

I gave you a thumbs up in the first 5 seconds of your video, because for once a RU-vidr who cuts to the chase at the start and isn’t just pandering for longer view time.

Awesome video Jeremy lots of ground covered, hahah, it's important to note that when attempting to use a VFD in any application single phase or three phase using flexible metal conduit or metal conduit in your application at least from the drive to the motor, note to observe the ground termination points as most likely there will be two locations the input ground ,and motor ground will have each a single point of connection at the drive (vfd). This is to help isolate any switching harmonics from the six pulse rectifying bridge from entering the system.. It might be worth mentioning if you're going to do this on a very large motor in a residential home may want to use an isolation transformer at the rated load. As the input to the drive , most expensive installed ,but truly its the least expensive ....peace

Well done. I learned a lot; and, I especially appreciate your attention to safety.

I had no other choice but to sign-in to like and subscribed because your explanation is just OUTSTANDING especially considering the content you cover. I would literally like your videos a thousand time if I could ... :D

Really great series of videos on motor control. I have copied the first and second option and very happy. Thanks Jeremy