Three Ways To Run A Three Phase Motor On Single Phase, And the Pro's and Con's of Each Method
HTML-код
- Опубликовано: 21 авг 2024
- I show in detail three different methods for powering a three-phase motor with single phase power. I show all the parts, how they work together, and the pros and cons of each method. The goal is to also explain how it works, not just “put the wires here”.
If you want to chip in a few bucks to support these projects and teaching videos, please visit my Patreon page or Buy Me a Coffee.
/ jeremyfieldingsr
www.buymeacoff...
Social media
Instagram www.instagram....
Twitter / jeremy_fielding
My websites www.jeremyfiel...
www.fatherhood...
My other channel - Fatherhood engineered
/ @fatherhoodengineered
************************************
Notes:
1. Potential relays come in different ratings. So, you have to be sure you get one that matches the voltage of your motor. The one I show in the video says is is for "any potential" as long as the motor is rated for 120, or 240. Details in the link below.
2. Affiliate links to Amazon items shown in this video. Amazon gives me a small commission if you use the links below. Feel free to shop around though.
Packard Start Capacitor
amzn.to/2QiC22w
Supco Potential Relay
amzn.to/2QiqhsO
Powerwell Run Capacitor 60 mf
amzn.to/2NzxSV8
Genteq Run Capacitor 35 mf
amzn.to/2CCBKAI
One example of a KB electronics VFD for 1 ph-3ph rated at 5.5 amps. Make sure you get one that's the right size for your application. Not necessarily this one.
amzn.to/2CDnOGA
Technical corrections
Nothing yet
Final Note:
PLEASE UNDERSTAND...I receive hundreds of messages on all platforms (email, Facebook, comments etc) asking for advice, and help with projects. At this volume, I simply can't do one on one advice. Thanks for your understanding on this.
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 RUclips was invented. To teach and help. Very smart man. Love the videos.
Thank you!
I agree
@@leeverrill hi
RUclips was created as a dating site 😂😂
@@BeyondThePines0 And Tinder was a basket weaving forum.
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.
Hello sir where are you from?
@NostradamusJr. I totally agree, and that applies to many different fields. Having been an Auto Technician for 23 years in a former career, and now, 20 years in Retail IT Systems (Holy crap, I just did the math on that. Damn, I'm old.), the bulk of my formal training in both fields was mainly hands on and accompanied by "book" training. That's called kinesthetic learning, and the way most humans learn the best. You can't understand how to use a screwdriver by reading the procedure.
BTW, My unofficial apprenticeship in electrical started when I was 6 and tore my moms toaster apart. I still have a love, and fascination with wrangling my personal angry pixies and respect for the guys who wrangle them for a living. Be safe, sir.
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.
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.
you Sir are the MR Rogers of electrical engineering, people can learn a lot from your vids!
Totally agree, an excellent teacher, makes what he is describing simple enough I can even understand. That is pretty amazing. Thank you very much Sir!!!
The Captain Kangaroo for do it yourselfer's. You learn and have fun doing it. Then again I was the only child at 3 experimenting with wall outlets. Yeah I am probably the reason for childproofing home ideas.
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!
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 !!
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.
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!! 🇺🇸
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.
How’d you get that job. I’m a maintenance technician and I’m waiting for some official training on Allen Bradley 1305, 1355, Ultra 3000, etc, instead of mostly guess work that I’ve been doing for years now. I’ll owe the company a couple years after I’m done but then I’ll be free to pursue other options. Could u give me some advice?
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.
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".
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.
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.
@Wayne M I've done it using a small single phase motor coupled to the pony motor to spin it up. You get creative when you have a pile of free motors.
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
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.
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 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
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).
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.
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.
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.
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.
@Kenneth Wheeler: I was wondering if anybody would finally provide the "5th" way.... (4th way is to just kick the pulley with your foot!) which is the cheapest, and best way to do this! Good job! Do you happen to still have that wiring diagram? I sure would like to get a copy!
Excellent teacher. Clear and concise. Speaks in a language I can understand even though I am not good with electrical work.
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 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.
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"
This is a lot of information. Good to see you show the "not so good" options along with good options.
@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.
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.
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.
i will highly recommend this channel to all my friends that tinker with motors and tools. You, sir are a master, bravo!
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.
Essentially, your systems are the fundamentals of a rotary phase converter. Correct?
Sounds like set up a fellow I knew had. He had a huge compressor in his garage that took 3 phase but he only had single phase power. He had a very large motor on the floor, we would turn the shaft as fast as we could with our feet and apply power to get it started then he had the compressor hooked to it and after we got it started up he would hit the switch on the 3 phase compressor and it would start right up and run.
He later got a 3 phase converter with huge capacitors but that thing sounded like it was going to blow up to start the compressor
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.
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.
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'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 ;^)
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.
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
Dude. You are the best. Your fanboying over that potential relay cracked me up. Thank you.
Wow ..very educational .. learned more watching this video then I have in 32 years of hands on
Thanks!
I have found your videos better than instructional sessions I had in college on these subjects, when studying for my electromechanical degree. Truly superior.
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.
Your a natural educator! I wish I would have been able to see these videos while in college. Makes a lot more sense now!!
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.
Ive been trying to get into this for a while.....watched loads of other vids.....but this series has been brilliant...thanks loads!!
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
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.
I built a rotary phase converter for my shop 15 years ago still works great this is really good information sir
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 don't think I have ever seen a better video than this one on RUclips or even elsewhere. Thank you very much for this helpful topic, and thank god for providing a knowledge angel as you!
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.
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...
What a brilliant video. Someone who actually openly shares knowledge. Thank you for sharing.
Automatic "Thumbs up" before I started watching... You are Awesome Sir! 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.
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.
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.
Dale Gribble, I love your comment about the smoke leaking out. I first heard that about 25 years ago from a friend of mines son.
The way he worded it was, "Once all the Blue Smoke gets out you can not get it all back in and the tool never works the same again". I adopted the expression then and only a few times have I heard others using it, you being one most recently. Love it.
Cheers from John, Australia.
Several people do exactly that with their setup. My goal for this video was to use as few parts as possible to show how "simple" it can be. Personally I would want displays showing voltage across each leg and several other things but then it looks more complicated and people think they can't do it. This is why I started with just one cap and built it up. But I agree with your statement completely.
It's definitely hard to get the factory smoke back in.
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
nice stuff, smart teacher , good way to teaching ,very clear and accurate , no body is better than you here on RUclips ,you are the men, i know because this was my job before
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.
⚒🛠🔧⚙️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. 🍺🍺🍺🍺🍺
I run a 3 phase 5 hp Ironworker, with a rotary phase converter. I chose the rotary phase over a VFD because of cost. I was given a 15 hp 3 phase motor and purchased the rest of the components for about $300. With this, I can start up to a 7 hp 3 phase motor adding up to 45 hp with other motors, starting them one at a time. The VFD capacity should be twice the hp rating of the motor you wish to run and the cost for a 10 hp rated vfd was $1200! As I'm planning on adding other 3 phase equipment, the rotary phase was a one time cost of $300. This thing works flawlessly! Pulls a bit of power to start, but when running, uses less than my single phase welder. The plus side, is that any components that need replacing are relatively inexpensive.
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.
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.
Bing your videos. You're a great teacher. So easy to listen to and understand no matter the listeners knowledge level
What a lucid description of 3-Phase motors. Well done.
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.
Thank you for the kind words and your thoughts on this project
You sir are a gentleman and an electrical scholar. Thank you for your videos, they are greatly appreciated!
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.
Excellent discussion on a topic that confuses many home shop folks . Thanks .
Brilliant teacher, explaining in an easy to understand way. This video has helped me, so I thank you for sharing your knowledge.
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!! 🤑
Great video, I've been waiting for a video like this for a while.. thank you for taking the time to post it . 👍👌🏽
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.
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.
Great video Jeremy,
very informative, keep up the great work.
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,
He is the gift that keeps giving !!
40 years ago, in my first shop, I made a rotary phase converter similar to the last one you show. Worked fine for years. I didn't have the relay so just used a momentary contact switch. I put the caps in a wooden box just in case something went wrong. Probably should have been a fiberglass box.
I'm now retired and going to move away from my commercial shop to home but still want my 3 phase tools so will be making another converter. I plan to just use one of the tools as the "pony." Should be able to run several tools at once. Not sure the run caps need to be left in the circuit after startup.
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
I bought a 220 / 480V Delta cabinet saw at auction. I had planned on using a VFD that costs around $260, but I choked on the 3hp and ended up getting a 5hp, so the VFDs were running aroung $800. I found a Delta VFD for $448 on ebay. It is a pretty advanced VFD with over 100 programmable settings. I use the ramp up/down features and there is a terminal board to which I have inserted a foot pedal control so that I can operate the power hands free.
In my opinion a good VFD is the best way to go no matter the price. I also had to rewire the motor from 480V to 220V. Or from wye to delta.
Fantastic explanation. This is how I run my milling machine.
Jeremy, Very well done and explained! TECO makes what seems very reasonably priced VFD's. If your motor is small enough, you can get 120 volt input. The last method can be achieved with no capacitors. Just make up a method to spin the motor and turn the electricity on. The one I saw was 20 hp motor with a pulley on so you can pull a rope to start the rotation. No capacitors and is able to run 22 hp of motors. Thanks for the video. Respectfully.
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...
A quick warning concerning the potential relay : **if memory serves well** the potential relay failure mode (either coil disconnected, or coil failed, or contacts stuck) is that the normally closed contact for the start capacitor STAYS CLOSED (please correct me if i'm wrong). So if it fails, il will put the start cap at work all the time, with almost 100% of it failing. This is why i prefer to use a momentary "normally open" switches for the start cap, which fails open, thus zero chance to blow the cap anyway. I hope i'm not mistaken, it's been a while since i used a potential relay. Thanks a LOT for your very helpful videos, they are very well made and you're a natural when it comes to explaining things, which is a great present you offer us.
You are correct there, but if you have equipment that cycles automatically, then the momentary switch won't be feasible. Well design systems would have interlocks to disconnect power to the motor in case there is a failure on the "potential relay".
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!
The start capacitors are generally 100 microfarads per horsepower. I did this with my clausing lathe so that the seven and a half horsepower motor essentially became its own rotary phase converter and now and when it's at idle it's basically the power station for the shop and will power my mill, surface grinder bandsaw, and die press. I balance the loads within 8v and 1A with run capacitors from L1 to ghost L2 to ghost then you balance L1 and L2 to bring the amps down. I could go further with to get it even closer but for my application its 👌
Also a simple magnetic starter contact works great you get them cheap at an HVAC store for like 10 bucks and a double momentary switch. One side of the switch to activate the magnetic contactor and the other side of the switch to activate the start capacitor. Potential relays sometimes fail and I just didn't want that in my application. All you need is a knife switch, a E stop, and a momentary switch. But for safety it is nice to have a three-pole breaker to protect anything upstream IE the capacitors if something were to happen to the motor.
Also great job on the presentation keep up the great work 🤟
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!!
Reading the voltage across run capacitor is Cool. Many Refrigerators used Current relays- the coil in series, Potential used parallel voltage, originally a more expensive method, where voltage is higher than line voltage, caused from back EMF. Seeing EMF with a meter can be a-kin to Christmas. Be careful with voltages higher than utility power.
Hello Jeremy, I enjoy watching your videos and really I'm not very knowledgeable about electricity but having said that I worked at a small shop for a couple of years that had no three phase power and they had been running 3 surface grinders, 3 Bridgeport Milling machines + 2 engine lathes all on 220 volt single phase. There was no phase converter as such but we used a 2 horsepower and then I believe later on a 5 horsepower idler motor which we would bring up the speed with a 110 volt washing machine motor connected with a V belt once The Idler had been brought up to speed we kicked off the v-belt and shut the 110 volt motor down and we were able to run all of these machines for years. The only problem while using a wattless third leg was when the Mills and lathes were running simultaneously sometimes The Idler would shut down for lack of capacity at which time we stopped running one or two of the machines in order to lighten the load and I suppose a seven and a half or 10 horsepower idler would have helped the problem because I was told that The Idler horsepower needed to equal the total horsepower of all the machines together although the most powerful machine was a 7 and 1/2 horsepower lathe. As I said this situation went on for years until they moved to an area where there was three phase available and we also had no need for variable speed as this was done on the Mills and the lathes by way of gearing and not motor RPM control. Once again Jeremy I really appreciate your videos and as I am past 80 years old they are entertaining and enlightening for me to watch your videos and so I hope you'll forgive me for making a comment about the way you phrase some of your sentences which is very very common today but is redundant and certainly not necessary please take this comment lightheartedly. When you say I'm now going to go ahead and turn on the machine, the words I'm now going to go ahead, are not necessary and in my day you would simply say I'm going to turn the machine on, not I'm going to go ahead and. Keep up the great work, you have a excellent speaking voice and an obvious grasp the subject material that you're are showing in your videos equaling a very smart fellow. Sincerely, your enthusiastic fan.
Great Video! The way you explained the starting relay was perfect.
Well done. I learned a lot; and, I especially appreciate your attention to safety.
You can also use a single phase motor with pulleys and a belt connected to a 3 phase motor to get it spinning, once it gets up to speed, a double pole double throw switch can cut the power to the starter motor as it supplies power to the 3 phase motor as long as they are the same voltage. Then you run wires from the 3 poles of the 3 phase motor ( that is powered and running with single phase power) to a 3 pole main breaker and from there you can hook up your 3 phase equipment. The HP of the motor you use to generate the 3rd pole power should be larger or equal to the motor you are powering, I have 230v single phase.
I am going to do this with a 13hp 3 phase motor I have, but my Mill is 480v, so I bought 3 single phase step up transformers to take the 240 3 phase to 480. You have to make sure the VA rating of the transformers will handle your amp load . If it is rated at 10 amps at 240v, the output will be 20 amps at 480v because as voltage increases, amps decrease.
My 3 Transformers are single phase, so what I do is is take lets say line 1 , 2 and 3 from my 3 phase breaker 240v and hook 1 and 2 to the input of one transformer, 1 and 3 to the next transformer and 2 and 3 to the third transformer, this is know as a delta wiring configuration
On the outputs of the transformer, I hook one wire from each transformer to a Neutral connection which goes to ground, the 3 wires left over , one from each transformer and the neutral will go to my 3 phase 480 volt panel, This is called a Wye configuration wiring on the output..
I can still get 240v single phase from my 480v 3 phase panel if I use a single breaker and run a ground just as you wire a 120v single phase supply.
In Europe they use 240v to most of their appliances, instead of a ground and two 120v wires, they use a ground and one 240v wire with a neutral for case ground. It is crazy
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.
Using a seperate motor as a phase converter is a very old school trick. Many of home machine shops have done this. But if you are powering a small single motor the VFD with a phase convertor is the way to go. Amazon has some china made versions that will run a 2hp off of 110v for 80-90 bucks.
This is good to know info! I'll have to keep this video handy! Thanks for posting this
i was going to say the same thing, lol
Very nice video indeed!
You have just proven the fact that Gerard Morin is right.
The last minutes in you start talking about how you can run more motors without having the power.
Now this has al to do with the hertz freqentie of the current. Never the less good video!
Please look him up Gerard Morin he's a very smart guy and could use any support!
Keep it up and keep em coming!