This is a 2 part video covering THREE PHASE CONVERTERS for your machine shop. Watch both parts. Please like & subscribe #machineshop#machinist#southbendlathe#lathe#millingmachine#atlaslathe
Before I had 3 phase I made a converter. Pretty easy and I suspect you can find all the info online now. Any 3 phase motor is capable of generating the 3rd leg. all you need is some way to start it on single phase. Some heavy capacitors will do it but be very carful as they are quite risky. I've had 3 phase for my business for many years. If possible I never buy single phase equipment. Too many hassles with the centrifugal switches and capacitors. Most machines with 3 phase made for the US market are either 208 (newer system,) 230+- or 460+- If you buy a European machine it will likely have a 380/400 volt motor and you will need to buy a transformer or some VFD's will also provide 400 V, (not common in the US) The advantage of using 460V is the smaller wiring, conduit and contactors that can be used. The disadvantage It will likely kill you if you come in contact with it. Where I live they will no longer provide 220/240V but 208V instead. It is easier for the power company to balance their loads with 208V. For our northern neighbors their 3 phase is generally provided @ 575 V so if you buy any used Canadian equipment be aware!
I recently replaced my static phase converter with a 5 horse rotary phase converter. I bought mine from North America Phase Converters cost me $500. Wired at myself, fairly simple. It works great! No problem at all for it to supply 3 phase power to the 2 HP motor on my Bridgeport AND the 1.5 HP motor on my lathe.
i worked in an old mans shop behind his home. he had a big 3 phase motor with a rope start. Wind the rope around the hub and pull then right away turn the power on. wire two legs of the power in to two of the three legs of the motor. then wire three phase out by connecting to all three legs of the motor. I have found that the larger and heavier older motors with lots of armature mass work better as they slow down less when starting or reversing the machines. I later added a small 1/4 horse motor for starting when in my own garage shop. 3450 rpm motors were too loud and i tried to use 1750 rpm motors. They worked very well for me.
Valuable information for people trying to power their garage/basement shops! FYI, it's also very easy to build your own rotary phase converter using a three phase motor with equal or grater HP rating then what you are powering. There is some great videos and write ups on the internet. I built the one for my Bridgeport, works flawlessly and way cheaper than buying even a used one.
Mr Pete, This and the next video on electricity will have more comments than you could have dreamed. Lots of questions, lots of DIY I do it this way, lots of arm chair experts, and some that really know what they are talking about! I like to read and laugh most of the time, but once in a while, you just can’t bite your tongue any more. Best wishes Sir! Kevin
Thank you so much for this. Of all your subscribers I will admit I am the most electrically illiterate especially on phase conversion and Keith will vouch for that. Can't wait for part 2👍
Wish I know 25% of things that you know and all the great things that you have made. Remarkable extremely knowledgeable great life long teacher. Wish more of our youth would get into trades.
The farmer next to our acreage has a grain dryer and bin set-up with three phase power. He pays $75.00 per month to keep the set-up active, sort of like rent. But then he is on demand so kick that corn dryer on and the $75.00 sounds cheap. But the dryer and bins only run in the fall and a short time in the spring or summer to empty the bins. But your point Mr. Pete is very valid, even if you could get the power company to supply 3 phase to you doesn't mean it is a simple watt hour meter. There is a fixed cost just to keep the three transformers hanging on the pole. Great video and explanation.
Lyle those clamp on amp meters use soft iron arms to measure the current. It IS important that the 2 mating faces are CLEAN when they come together That’s probably why you are getting inconsistent readings on the digital one. Give them a wipe over or even a gentle rub with emery to remove any rust etc. Hope this helps. Regards from Australia
I really enjoyed the video. I was wanting to learn more about how these worked. Your video came up at the right time! Greetings from Ottawa. 🤠 I have quite a few friends in Streator
Hi, Lyle I just noticed the manufacture on your phase converter. The Phase A Matic , is manufactured about half way between Palmdale, and Lancaster, just West of the Lockheed Skunk works, Plant 54. I have a 5 HP one, and it has preformed flawlessly for several decades. I have built several others just like this one, out of junked motors, and other junked components, and they all worked perfectly. No special starter circuits, or trick electronics, just a few large in Microfarad capacitors to balance the three legs a bit. They all run a bit noisy, but putting them up on rubber standoffs works, as does using some repurposes used valve springs. I keep thinking I will build a cover outside for it, but I have too many other projects in the works. The 5 HP 3 phase 240 volt motors have run everything in My shop from 5 HP mills and lathes on down with no problems. I have never had a failure, even though these motors are very old. Just changed the bearings to make sure , and ohm ed them all out to check for opens/shorts to ground etc. Not hard to wire up at all. Lots of simple plans on line. I have been using European 3 phase plugs, and sockets, as they are much cheaper than American ones, and very easy to work with. I think these German folks have got it made with 400 Volt 3 Phase power to every home. I taught taught Auto Shop in the Antelope Valley School district which covers a large part of the area around these cities. You might remember my partner and I talking with you as you left the Bar Z Bash a few years ago. We both taught in the Antelope Valley school district, just on the North side of the mountain where the Bar Z Bash was held. Hope to see you at the Bash again some time. Tim
Lyle - Good explanation of what becomes a complex subject fairly quickly. I would say that anyone who has done home wiring safely and correctly can study up some and successfully build a simple rotary phase converter. The simplest versions are just an old 3 phase motor, some wire and a rope to start up the 'home brew' converter. But as you said, get some help if you are not comfortable or have no experience with such things. Many of us have built and/or modified such systems.
Lyle, I thought the same thing about 3 phase in residential areas. I live in the middle of a residential tract. (No businesses close by.) Had a guy come over to look at our dying AC on the roof. He said we have 3 phase power. I thought he didn't know what he was talking about. We CAN'T have 3 phase! Then I went to look at the breaker panel. Took the cover off to see inside.(Didn't need to do that, if I'd just look at the breakers.) Some single breakers, and some double ganged breakers, all separated by an unused spot. Then I looked at the AC breakers, triple ganged! steve
@@mrpete222, either had i. The whole neighborhood is wired for 3 phase. Just so you know, I repair all kinds of woodworking equipment, and am quite familiar with 3 phase stuff. (Just never bothered to look at the house breaker panel, concerning 3 phase.) steve
You're a legend Pete ! I'm a native french speaker and yet the pace of your voice makes each word understandable and the whole videos the best lessons, thanks a lot !
I think it is interesting to see how electricity is solved in different countries. I'm Swedish and here everything is 3-phase. There are houses that are connected with 1-phase but it is very unusual. A standard house in Sweden has a 4-wire system (3-phases plus common earth/neutral), 400V between the phases and 3x16A main fuses. The electrical outlets in the different rooms are 230V 1-phase - phase, neutral and earth (you split neutral and earth in the fuse-box, which is placed central in the house). The advantage of having access to 3 phases is that you can distribute the load from all the rooms in the house on the 3 incoming phases and thus get down to the size/area on the cables that feed the house itself. It simply becomes cheaper and more reliable.
I live on small acreage in South Texas served by a rural electric coop. When I was about to retire my wife built me a metal barn for a shop. The coop has a 3-phase main line running through my property, but gave me all kinds of reasons and general resistance to hooking up 3-phase to new shop, but FINALLY gave in. One of the reasons for not doing it was getting wires from pole to shop...the were going to charge $2500/pole, another pole every 400ft. I asked them where they had to put the first pole off the main line and they said 40 feet. Miraculously, the corner of the shop where the power comes in is 39 feet from main line....what a lucky break! Additional cost was $1800 and well worth the money. BTW: you say that 3 phase is more efficient for motors, and i understand why. But, HOW MUCH more efficient? 10%, 30&, 50%??? I can't seem to find the answer to that question anywhere. Nice Video, thanks
A motor after start up uses the same power to run regardless of wiring. A 1 hp motor uses the same power running wether single phase or 240 volt or 3 phasse. When you test the amperage of a 3 phase motor you have to add the amperage of the three wiires to get the total amperage the motor uses. Likewise you have to add the amperage of the 2 wires on a 240 volt motor to get the total amperage the motor uses. On a single phase motor (120 volt) you just need the amperage of one wire to get the total amperage. This is why you can use smaller wires to run the different motors. This can add up substantially when running big motors. All things being equal as the motors are made the same they will use the same power to run regardless. Hope this helps as there seems to be a lot of misconception about this. Dale in Canada
@1:53 Other than the US, most houses and sometimes even individual rented flats in a multi tenant house here in Germany, and as far as I know many other European countries, are provided with 3 phase power. That’s very convenient, as you could easily have an electrician put a 3 phase socket in your garage or workshop.
In the EU, the whole electrical grid is 3 phase. If a house has only single phase, it's still 3 phase in the street - just a matter of running the other 2 phases to the house. The typical layout of feeds to houses is that the first house is on phase 1, 2nd house on phase 2 and 3rd house on 3. Then back onto 1 again for the 4th house etc.
I was moving some grain at a place I worked at in Kansas and heard a loud “pop” outside. The sound of the grain leg instantly changed for it was 3 phase. Upon further investigation, I had found that a sparrow had shorted out one of the electrical feeds on the transformer pole outside. That sparrow had caused the pole fuse to burn out. The poor sparrow was nothing more then smoldering feathers.
A timely video for me. I'm currently building my own converter. The experience has been extremely educational with regard to electricity in general and more specifically to contactors, capacitors, stepdown transformers and control circuits.
S Bird Ranch did a series on building one, I found it to be quite educational. You might look it up if you are researching various ways of going about it.
Timely, my daughter and her husband are opening a custom butchering shop, and got great deals on 3 phase equipment. They are putting in a 22 Hp Phase converter. One thing to remember, even if you hire a professional electrician, is that a phase converter is a "service", even if it is hooked up in series from your properties service where the power meter is located. So be certain the electrician wires it as such. Not all do, or some will quote you a lower price to get the business and skip a few steps. There are a lot of good deals on 3 phase equipment. My Sheldon Lathe is 3 phase. It is a real shame that Electric companies won't put 3 phase everywhere. You would think with all the hoopla over energy savings they would install it with a smile.
Absolutely mint to hear from a man who is confident in rotary phase converters. What you say of 3 Ph. is true of this overseas country also and the best workshop equiptment is always available in just that. Here where I am VFDs get some retail promotion but rotary converters are home made usually and not encouraged by electrical trades. I prefer the more flexible source of rotary converter in theory, but have not dared to make the leap yet.
As someone who has worked in shops with both VFDs and RPCs, I almost prefer the RPC for it's simplicity, though i very much appreciate a VFD's ability to replace aging motor contactors and provide fine control over the motor start, stop, and speed. RPCs are much better for the long term I think. The motor is likely to never fail, and capacators and contractors are easily available. My boss ran his entire shop on 3 or 4 RPCs, an '80s Mazak CNC on a 40hp, a 90's Haas VF4 on a 20hp, and everything else on a 10hp. Larger converters do require 400a service though.
Been using a Phase-a-matic for my lathe and mill for years and years and years. My father used his Phase-a-matic before me for 30 years. Absolutely trouble free and reliable. As you said about the only drawback is the noise - I have mine mounted outside the shop - solved that problem.
Yes I am interested in this information. As for explaining the 3 phase power thing? Imagine one man pushing a 500 pound wheel for one second. Can he do it? Yes, but its very hard. He has to find his footing, and push with all of his might and that is going to move the wheel about 2 feet. If he has two friends pushing, but only once he's expended his push and is trying to find his footing again, and each pushes in turn so its 1push, 2push, 3push, 1push, they can get the wheel moving quicker, go faster, and keep it moving constantly. This is why three phase power works great with electric motors, and also why you can make mechanical phase converters, rotary phase converters and digital too. I think its important for folks to know this, because electric cars even though battery powered use 3-phase power to move them. I still think this is highly ironic. Why? 3-Phase power has been around since about 1880 or so powering electric motors, including Edison's Electric Cars which were made up to about 1930. Every time I think of Edison? and his rock star image? it makes me laugh because Musk is about the same way.
I have used an 3 phase inverter for years on a lathe and mill. the ability to dial in a soft start. This is particularly valuable in an operation requiring frequent direction reversals. The inrush current of the stop start cycling can over heat and damage the motor, it happened to me using a rotary converter.
I built a rotary phase converter for my Dad's shop back in the 1970's My shop uses one I built 20 years ago. Both were built from cast-off materials. Mine sits on a foam pad as yours does. The cost, and availability of the rotary converter is such today that I would buy, instead of build. Thanks for this video Lyle.
I built mine about the same time with air conditioning parts disgarded at work. But bought store bought recently for my mill and lathe and my old one for my big Rockwell variable spped drill press
I bet your home-built are of the lesser quality type. Some RPC are now proper rotary transformers - single phase in 3 phase out from the generator section of the RPC.
@@millomweb I don't understand what you mean by lesser quality, but my RPC home build powered my Bridgeport as well as the the three phase powered the Bridgeports in the factories I worked in all my life.
the fluke current clamp is trueRMS, which might be why the reading on it is different than on the rest of them, but it'd be more accurate, not less accurate
Most interesting. All my Machines are 110-volt so that I can run them from auxiliary power in case of emergency. But you have explained it thoroughly now at least I understand 3 phase power thank you
I used a rotary phase converter for years and it performed its job but I hated it. It was so noisy, you had to turn it on first which was bothersome especially if your equipment was scattered so you had to walk to the switch and finally if you were using multiple motors you are supposed to start the biggest motor first-then the next biggest etc.. I switched to a digital full shop converter by Phase Perfect. It is on all the time, they come in different sizes but mine will handle up to 10 hp total, it’s noise level is that of computer fans which come on infrequently when necessary to maintain its temperature, power loss is only 2%, it is a more balanced 3 phase than the power company so get full hp out of your machinery, you can turn the motors on in any order regardless of hp, and did I mention it is on all the time😉. Best thing I ever did in my shop and I have no financial interest in this great product.
Hey Mr Pete thank you for explaining these issues - I know enough about electricity to hire a professional. My Bridgeport gets power through an electrical circuit loaded with capacitors, which powers a single phase 1 hp motor belted to a 5 hp motor that connects to the mill (I think I have this sequence correct). On my south bend lathe, I have a computerized converter the size of a shoebox that converts power to 3 phase. It features controls like changing rpm’s by changing power, and direction of spindle rotation. Again, beyond my wheelhouse. Thanks, John
3 phase power frightens most home shop folk, but it is worth considering. Industrial machines over 1HP are normally 3 phase and can be purchased used for lower cost than their single phase versions due to the prevailing fear of 3 phase. I purchased an extremely large gear head DoAll drill press for $100 simply because my competing bidders were afraid of 3 phase. I purchased an industrial Wilton 6" belt sander for the same price and for the same reason. I knew that it had a 3 phase plug on the cord, but I also knew it was a single phase machine. I am just a hobbyist, but I currently own five 3 phase machines. I run one on a VFD, but the others use a rotary phase converter. I am setting up my commercial 3 phase rotary converter right now. I have run for years on my home built converter. Explaining 3 phase versus single phase is a large subject. Lyle's simple explanation is helpful and sufficient. I will attempt to go deeper for the nerds that want to understand more, but I will make some generalization for the sake of brevity. AC 3 phase is generated by the utility with the phases 120 degrees apart. Single phase is obtained by any two legs of the 3 phase power. The utility transmits 3 phase power and splits off single phase as demand requires. If you are located in a densely populated area, 3 phase is very close, but rural areas frequently are fed by only single phase. Getting 3phase to your home is costly because the utility doesn't set up transformers for the purpose without the user paying for the cost. Single phase is delivered at "the utility's expense". 3 phase gives rotation direction control be synching the motor windings to the supply rotation or switching two legs to reverse the rotation. Single phase motors need something to "imbalance" the AC supply current so the motor will always run the correct direction. Motor design accomplishes this in different ways. Shaded pole motors weaken the stator magnetic field. Machinery motors rely on start windings with or without start capacitors. Permanently split capacitor motors can run with just a run capacitor or can also use a start capacitors. A capacitor will cause the current to lead the supply current by 90 degrees. This gives the motor torque in two phases shifted 90 degrees and determines rotation direction. Start capacitors have much higher MFD than run capacitors and must be removed from the circuit to avoid failing the fine wire in the start winding. This is done with relays or mechanical throw out switches. Single phase motors are therefore more complex to manufacture and require capacitors and switching components for these applications. Single phase requires more current for the same HP since all the power is carried on two wires instead of three in three phase. 3 phase is perfectly balanced by design and shifts current flow to the other legs depending upon the relative rotation. Perfectly balanced also includes balanced torque. 3 phase allows instant motor rotation reversing, but to do this in single phase is complex. In simple single phase motor and control design, reversing the control of the spinning motor will have no reversing effect. The motors in this annoyingly long description are squirrel cage design. The magnetic field rotates via the wound stator creating Eddy currents (counter electromotive force) in the conductor bars of the rotor. The rotor is repelled by same magnetic polarity causing the rotor to turn. (Brushed motors, whether AC or DC, work on a different principle.) Speed of a common AC motor is determined by the frequency of the supply current and then by the number of poles wound into the stator. Motor design incorporates slip so the motor rotor turns slower than the revolving magnetic field created by the AC. The rotor is always trying to "catch up" to the magnetic field creating the torque. As load slows the rotor the torque increases causing the motor to draw more current and attempting to "catch up". So AC motor speed is dependent upon supply current frequency. This is why VFD's work to control motor speed. Increasing frequency rotates the magnetic field faster. The rotor follows the rotating field as I attempted to explain. VFD's are highly complex devices that I won't try to explain here. Torque is complex to manage when speed changes. When VFD technology was introduced it was very costly. This technology is now well understood and VFD's are now quite affordable. I have attempted to use lay language in my description. I have purposely left out vast amounts of information, so my explanation is not intended to be completely accurate. I am attempting to add some helpful information to the hobbyist reader. Motors 1 HP and larger require motor protection. Thermal overloads in the motor is adequate, but uncommon. You find this protection in high end home owner woodworking machinery. Industrial motors and those found in machine tools will have external motor protection. A device called a motor starter is employed. Motor protection is another major topic. Entire articles in the NEC are given just to motors, motor protection, control and supply. Grab a NEC and you will find lots of helpful information.
Was taught 50 years ago that a cord must never be used in place of permanent wiring. Inspectors never saud anything when I wired in a lot of Bridgepirts with the rubber cord that was on it. At a large candy plant that I worked at they wired mist things from illegal cheap cord thru a romex cinnector that mounted on cover of ictagon or 4 by 4" square boxes. Told them numerous times this was against the code. Any way OSHA came in and had a field day. They told them machines have to be portable ( on wheeks ) to have a cord with an approved strain relief . So the 6 sparkies each got over 150 hours OT each to bring plant up to code.
Thanks Mr. Pete - useful info. You can run some 3-phase motors on single phase, as long as you do do not use the machine hard or continuously. I have a three-phase radial arm saw that I start with a capacitor, and run on single-phase. In fact, that is what the rotary converter is doing - you start a three-phase motor from single-phase, then, you tap off the three-phase motor leads to run another three-phase machine tool. The motor on the converter supplies the third leg. Mr. Pete mentioned running multiple motors at once, and that can be beneficial - the more running motors on the lines, the smoother the power is.... up to a point - You cannot exceed the HP rating on the phase converter. But, idling motors in parallel produce a cleaner three-phase signal.
Mr. Tubel I use a 7.5hp/ 15hp max total rotory in my shop I put a 220v 2pole magnetic starter relay with a 110v coil on the input side of the RPC and use a remote controlled relay (from Menards) to energize the 110v coil. This allows me to turn the RPC on or off with the remote control FOB that way you can place the RPC away from the immediate area away from the noise. I have had this setup for the last 20 years no problems to date. You will find that as you get the RPC to its max advertised HP rating the quitter it will run. Cheers Zed
If you have a 3 phase motor, you can put together or even purchase complete a control box to make your own rotary phase converter, its basically a few start and run capacitors, a magnetic contactor and some wiring, I purchased a 5 hp one for a bit over $100 that I married to a used 5hp Baldor motor. Its a very economical way to roll your own 3 phase power, especially if you have a descent sized 3 phase motor kicking around already.
I built my first rotary phase converter many years ago to run my air compressor. All the parts were used/salvage finds and it worked great. Now after buying land and a large shop I need to decide what to use now, ie commercial or a larger rpc self built. I was just looking a 240v to 480v transformer also.
Thanks for this very interesting video. I have quite a bit of experience with three phase motors and always impressed with their starting torque. You might want to mention what happens when losing one of the three phases--quick way to let the smoke out of a good motor, if not properly protected.
#6 B - Better finish due to the uniformity of the torque. I built a 10 HP rotary for my shop. Works great. I found a cheap motor that had a foot broken off. Since it just idles away, it works perfectly. I put it on a tiny furniture dolly under a work bench. Control box is on the wall above. Very easy to use. The static phase-a-matic is just the control box portion of a rotary converter.
I read in a Hawkins' Handbook of 1907 of a conversion method called "Feraris-Arno". Upon further investigation, I learned that Feraris was an Italian contemporary of Nicola Tesla who tended to gravitate more to practical applications rather than the highly experimental work of Tesla, although they overlapped in a number of areas. Anyway, I discovered an article by Feraris which, although in Italian gave diagrams in standard electrical representation, which I understand. Taking this information and some salvaged components, I was able to construct a converter able to operate my LeBlond Regal, as well as other 3 phase equipment. It is pilot relay operated so if there is any interruption in the supply power, it shuts down, as well as be operated from satellite control stations so you don't have to leave the machine you want to use to turn it on or off. I just wish I had not mounted it on a rigid shelf attached to the structure of the building, as the wall acts as a sounding board, and, as you say, there is a fair amount of noise from it. The whole thing cost less than $100.00, maybe even less than $50, but I am an accomplished schrounger and have barterable skills. Should any reader feel the need for information, I am happy to help. Thanks for your effort in passing knowledge along to others.
Certain old neighborhoods in the Phoenix area were wired for 3phase due to the extreme heat in the city during the summer months and the large air conditioning loads. The AC/Heatpumps all had 3phase motors on them. Being able to feed enough power in Phoenix during the summer has always been a challenge for the power company. The fluctuating demand between the days and nights is quite dramatic.
@@infoanorexic Tucson is dryer than Phoenix so they solved the heat problem using evaporative cooling for the most part. Phoenix however is hotter and has higher levels of humidity due to having more surrounding bodies of water, so AC was always pretty much the norm there. Tucson's monsoon season has caused more people to move toward using AC systems. It's a miserable time of year if all you have is evap cooling.
Gas & Electric prices have skyrocketed it costs me almost as much to power & heat my 20,000 square foot shop as all other expenses combined. We are thinking of upgrading our air compressor from a 25hp to a 50hp thank god for rotary screw compressors the thought of having an 50hp compressor turn on and off 6 times an hour frightens me lol.
Very en-lighting Lyle and will explain. Both lathe & mill here have VFD's supplying power to there 3ph motors, and so far not noticed a big jump in utility cost, but they don't get a lot of daily use either. The Klopp will be also be feed of the one to the lathe (shared) but one day may build a rotary phase converter. Have the all the parts, including a 3cyl air cooled Deutz F3-L that will drive the generator motor, but future build of course (@@)! Weather sure put a damper working in our shop, and be glad when all our snow and ice melt off here. Have a great time dw at the FlyWheel event, and hello to all the other creators and enjoy the 4 days. Bear & Sammie.
17 years ago I went with 3 phase Rotary and created 220v 3 phase and then through a big Electrical box I used contactors.... and stepped it to 380v 3P and it drives my two big surface grinders.
The currents that you measured are probably almost all motor magnetising current. Small 3-phase AC motors typically require about 40% of their rated current to magnetise them. However, since this current is almost 90 degrees out-of-phase with the supply voltage, the real power (i.e watts that cost money) is very low.
MR PETE is the coolest kid on the block with the coolest toys! .. I always thought a phase converter only gives 2/3rds of the rated 3 phase motor horse power when used on a rotary converter? True?
One of the big advantages of 3-phase motors which you left off of your list is the ability to change speed. This is only possible though if you are using a VFD. I use a rotary phase converter on my milling machine but I also use a VFD for my lathe. They each have their advantages.
I gave this as a response to mark clauss below and thought others may have similar questions. - Ok, I'll give it a condensed try. Power stations generate and distribute 3 phase maybe at around 1kV). At a residential street, two legs of the 3 phase are connected to a single phase step down transformer (1kV) input, 220V (split) output, giving two 110 volt lines to the breaker panel. Sine waves are a type of alternating current generated by rotating a magnet inside a set of windings (in the case of 3 phase - a set of 3 windings, 120 degrees from each other) - a result of the physics and geometry of the generator. There are therefore 3 nearly identical sine waves coming out of the 3 legs of the generator, each shifted 120 degrees from the other. In order to generate a rotating magnetic field it is necessary to have at least two sine waves (in this case separated by 90 degrees). So in a single phase like we have in our homes a rotating magnetic field can't be generated without some sort of trickery. VFD is a newer way. The old way is to use some sort of delaying system to make a second phase (from the normal single phase in the house). There are various delaying techniques available. One common method is to use a capacitor in series with the second winding of the motor. This can be continuous like in most medium duty motors - table saws etc. (called capacitor run), or intermittent (called capacitor start motors). Obviously, with 3 phases you don't need any sort of delaying scheme to get a rotating magnetic field. I hope this is helpful. RPM
Lots of power options. I think a static converter is the worst option. VFD is a good choice but has its quirks. There are two types of rotary - typical converters and rotary transformers - which are a better option as they are genuine generators - but you can't get straight answers out of sales people - so I made certain by getting a diesel generator. Doubles up as emergency back up.
I had that fluke amp meter. It's made for big stuff, and doesn't have resolution for one and two amp stuff. That fluctuation at that low amperage is pretty normal. Fluke makes some now that are alot better on the bottom end.
Oh? Model number? I've got a Fluke amp clamp that isn't very useful under 10A. There's also a cheap UniT meter that does AC and DC current at low values, but I wouldn't trust it for anything critical.
Great video Mr Pete! The demo of the different meters and the various readings is very interesting! Running the extra motor is a small price to pay for the 3 phase performance for us small shop guys! Thanks for your time and sharing! Excitedly waiting for part 2n 👍😎
You can also build your own rotary phase converter yourself really cheap. The "rotary" part of the converter is nothing more than another 3 phase motor, that uses capacitors to start it (a 3 phase motor will run on single phase if it has some help starting). I've got a 10hp rotary phase converter that I have less than $100 in, but I got the idler motor free.
I install vfds at work and get old vfds from work basically free. But after using some for the shop for a year I went with rotary phase converters that I made myself. Kept finding really cheap like new motors local so kept selling the previous models to friends. Made a 15, 20, 25 and 30 hp models now. If I didn't have a10hp air compressor I would never have gone that big. But biggest problem with vfd is u have to remove the magnetic starters and wire directly to motor otherwise your very likely to burn out the magnetic starter because of the high carrier frequency they produce.
For a truely crazy electrical setup you have a shop like mine with 120 and 240V single phase as well as 240V and 480V 3 phase all done from one supply. :-)
For a shop with a few older 3 phase powered machines, a Rotary Phase Converter can be very cost effective, especially if there is more than one 3 phase motor to drive in each piece of equipment. RPCs can be built or purchased; you probably won't save any money if you build your own (correctly), but with DIY, it is easier to match it to your load motor(s) to get less current draw, and a more balanced output. An RPC can be made *very* efficient, but requires a lot Capacitor Swapping/ Adding/ Removal (with lots of volt/amperage readings in between) to get it optimized. The trouble with perfection in this case is that a "perfect" setting for one load motor will hardly ever translate to the same result for a different load motor.
You want the other version of a converter - a rotary transformer - which some RPCs are. No messing with capacitors, it's a combined 1 ph motor and 3 ph generator in the same casing.
There actually are some residential areas that are supplied with 3 phase to the house. Around here, a good chunk of the old neighborhoods in Phoenix were done this way with 4 wire open delta service for the old central A/C units with a 3phase compressor motor. I understand some of the old homes on the east coast were this way as well. I live in a rural area just outside of Phoenix in an area with a heavy concentration of farming and ranching, and was told by the power company that it wouldn't be a huge deal to supply my property with 3 phase if I really wanted it, though I would have to cough up a few thousand dollars to get it done.
I live in Chicago and use a rotary converter to power my machines, but in recent years Con Ed has up graded their power lines, so now I get close to 250V and it's making my motors saturate and vibrate on starting. I now have to get a transformer to lower the voltage I feed the rotary to 230V
Thanks for the excellent refresher on 3 phase power and static and rotary converters. I have both in my shop, the static to run the Bridgeport and the rotary for the surface grinder. Static did not provide enough power for my 1 HP surface grinder so I had to purchase the rotary unit for it. Interesting that the quiet static converter works fine on the 2HP Bridgeport.
The statics come in power ranges like anything else. I've a 7.5 HP static - so will run 1 or 2 3HP motors - there's a knob on it to 'tune' it to the power being drawn. I've switched to a diesel generator !
@@millomweb No, Phase A Magic is just a trade name. The static model comes in different HP ranges such as 1 to 3 or 5 to 8 etc.You have to use the correct model and not go over.
In Euope, Sweden, 3 phase is standard in free standing houses much due to electrical heating. Owens using 3 phase is also common, washing machines and so on. That way the size of the main fuses can be kept lower, saving money.
Wish we had that in the US but you go with what you have especially when it is such a huge developed electrical grid. A change over would be unthinkably expensive. Variable frequency drives have made it a much smaller problem.
@@bruceanderson9461 Are there 3 phase converters with built in VFD powered by 110 volt? That would be really handy. Here "bad guys" are cutting and stealing copper wires almost daily. Railroads get in trouble.... Using 110 volt, like in the US, forces the cables to be significantly thicker and more attractive for thieves.
@@Stefan_Boerjesson I am not an expert in vfd and the one I use is on 220 volts which is the standard voltage brought into homes in the USA. An internet search would probably answer your question. My main shop uses a digital phase converter that is on all the time, is quiet, and provides better 3 phase than the electrical company while providing full hp to my motors with only a 2% power loss.
@@bruceanderson9461 Whatching a number of machinist RU-vidrs that restore and use old machines quite a number of them only have 110 volt available.....
Here in NYC, much of the street lines are three phase. When I asked about three phase, I was to,d that sure, they would do it, but that it would be very expensive for what I wanted it for. Meanwhile,e, mt commercial photo lab had 600 amps per phase three phase.
For many years my grandfather just connected a 5 hp 3 phase motor to his mill and 220 single phase . Used a clothes line cord to pull start the motor. Once rotating it self generates the other leg. Rotary phase converters have capacitors to temporarily create the 3rd leg to start motor. Nothing really magic.
Thanks for doing your part to keep Com Ed profitable Mr Pete 🤣 Personally, I would have used a non-conductive pointer and not that metal one that you were using to point out the various parts. ⚡️
These are very simple to build from a three phase motor. The motor used for the converter will operate 3 times it rated HP. For example A 10 hp converter will operate 30 hp . The more running 3 phase motors in the shop, the smoother the generated third leg will be.
Every residential neighborhood in the US & Canada (and possibly in Mexico) has a 3 phase supply line feeding in, but the power companies step it down to ~220 V (208 to 240, depending upon your location) single phase before they make the connections to the residential - and most agricultural - customers. It's actually a bit more complex than that, because your typical residential service connection is actually two 110 v legs, and you need to have a circuit breaker that picks up from both legs to get 220 V, single phase, power. For a variety of reasons, even though I have a 5 kV, 3 phase local feeder running down my property line, ~10' from my garage, my power company will NOT give me a 3 phase, 220 V connection. I don't think that it would actually be illegal for them to provide 3 phase power, there are many bureaucratic hurdles., before you even get to the cost of such a connection. Some of their reasoning may have to do with the perception that 3 phase power is inherently more risky for homeowners to be monkeying around with, and the insurance lawyers are telling the power utility to make the residential consumers do their own aftermarket 3 phase work, in an effort to limit liability... Considering what I have seen some people do with ordinary 110 V circuits, I cannot entirely blame them... Meanwhile, your corner convenience store at the end of the block has 3 phase power to drive their refrigerators...
For some reason, three phase power was made available to all homes when my neighborhood was developed in the late 50’s. My neighbor has an original three phase motor on his HVAC unit. I could easily tie in with a separate meter if I wanted to.
Hi Mr. Pete! Could you please explain to us exactly how single phase power is generated at the power plant and how three phase power is generated at the same power plant. What are sine waves ? Are there 3 sine waves in three phase? Plus, Why do single phase motors have capacitors and three phase motors do not ? This is all so fascinating ! Thank You ! Mark
Power stations generate 3-phase, and it's transmitted as 3-phase. To get single phase your house is hooked up to one of the 3-phase lines. In Australia every third house is on a different phase, occasionally you'll get a blackout when one phase goes down so every third house goes dark. (I think in the USA they tend to run only one phase down each street.) As for motors, 3-phase ensure the motor spins in the correct direction at start-up. To over simplify, one coil may be fully energised and it's neighbour only partly so, so it'll start to spin as the magnetic fields are "out of balance". The start capacitor in a single phase "fakes" this by energising the start winding which is offset from the main winding, giving the motor enough torque to start spinning.
@@daviddauphin838 when Mr. Pete said, "Now you know what 3 phase power is"...I thought...No I don't...I don't know any more than when he started...he said it was hard to get...he told me that it is expensive to have "Brought " to a shop....He didn't really tell US what it IS !!! I know what 3 phase power is...I know how it is generated....I was being SARCASTIC...IT WAS A "TONGUE IN CHEEK" and un-necessary SARCASTIC comment...SHAME ON ME ! Mr. Pete is a COOL GUY ...but I think he is SLIPPING MENTALLY...I WILL TOO SOMEDAY...HOPEFULLY SOMEBODY WILL GENTLY WALK ME AWAY FROM RU-vid AND ALL SOCIAL MEDIA...
Hi Mr Pete - thanks again for the great videos! I’m a novice machinist setting up a new 1340 Lathe with a 3HP, 3-phase motor. The one I’d like to buy is an American Rotary 5HP basic model. Of course, they’re telling me to use a 10HP rotary converter model due to motor start up draw on the Lathe. My gut tells me that the 5HP converter model should be sufficient. What do you, or other experienced commenters think? They recommend double HP but the loss seems to be pretty marginal in this instance..
I should have watched this before commenting. I didn't know what it was I was looking at. The lumberyard I frequent has a big radial arm saw. They have two motors wired to it. The first motor doesn't run anything. They just start it up before starting the main motor that runs the saw. I have never seen that done before. Supposedly the first motor keeps the second motor from tripping the breaker. On another note. I prefer analog meters as well. In the first place that is what I learned on. And in the second place my son's don't borrow them from me.
The digital meter fluctuates because the measurement is between 2 and 3 Amps. You could estimate another (unspecified) digit by noting the time 2 is displayed vs. the time 3 is displayed. The residential grid contains only two wires (except in cities) so delivering 3-phase power would entail running a wire for the third phase. If you are not VERY close to a switching station, the power company would insist on running the wire all the way to the next switching station. This additional infrastructure would be at your expense. They might also charge extra for the 3-phase transformer at your home. Your home would need a 3-phase breaker box and circuits divided among three phases instead of 2-phases to keep the load balanced.
