3-Phase for the Shop: 3-Phase -vs- 1-Phase Power

[@MasterTheNEC]

Greetings Gavin - Nice explanation. However, you are aware that the remote distribution panel you show is a violation of 250.24(A)(5) right. You do not ties your grounded comductors, in your case neutrals, and equipment grounding conductors together. This creates objectionable currents as well and places unintentional current on metal parts. However, in terms of phasing and so on well done. Also that grounded conductor in your remote panel needs identification as a grounded conductor as well per Article 200.

[@aw738]

This was the best explanation of 3 phase I've ever seen.

[@Ultimatereloader]

Thanks!!!

[@randyscott990]

Great explanation Gavin. Your panel from your converter uses black, white and green. Kind of a no no. Electrons don’t care about insulation color and I’m of course referring to a business where city inspectors, building inspectors etc. have free access to a business, so in that regard, you’re a private entity so they’ll never know (unless they watched this video). The only problem that could arise if you go to sell the outpost and an inspection is required, they would ding you for that. Simple solution, use colored electrical tape to correct the wrong color. For example, put some red tape on each end of the white and blue at each end of the green. In your small shop it’s your kingdom and you did the work, if an electrician came in for some work he would have to $pend time figuring out your method to be safe. That green as a hot leg can get people hurt and confused. And I did see a comment where you’re going to add a ground to the lathe. Good idea. Back in the old days they didn’t have it but they DID need it, they just didn’t realize it. Dead people made the industry realize it. I see the incorrect use of insulation color often, but like I said, electrons don’t care. You do’t claim to be an electrician so you get a pass but your clean wiring and research allow your set up to work safely. Nice job, keep the excellent videos coming. And NICE outpost.

[@peterdietrich1785]

Kind of a no no is a massive understatement. Green should NEVER be used for current. It ALWAYS needs to be a Ground and tied to an earth or water ground at the main panel. Imaging someone accidentally energizing an entire machine body because a green wire is accidentally tied to a hot leg. With rubber vibration isolation mounts on a machine tool you are creating a potentially deadly situation.

[@1725Izzy]

In the NEC code book the only two colors regulations are white/grey for neutral and green/green with a yellow stripe for grounding

[@JohnSchenck]

I've used 3-phase in my data centers before and knew it's better but having this very straight forward walk through of 3-phase really clearly iiustrates exactly what is going on inside the 3-phase power panel. I've made myself somewhat known by saying over and over again "No 120V in my data center!" 208V is just more efficent. The one real advantage I see with 3 phase in the data center is a power run to the cabinet can offer a lot more amps without stressing each of the legs as much. But for a machine shop your walk through explains why 3-phase is so much better for a mill or lathe. Thanks for the simple consumable instruction. Look forward to more of your shop vids!

[@Ultimatereloader]

John Schenck thanks, glad it was helpful!

[@nunyabusiness2294]

wow. best explanation of 3 phase power on the internet.

[@sethvermaaten7584]

Very good dissection of power and three phase vs. single phase! Brings back good memories from college and physics classes!

[@Ultimatereloader]

Thanks Seth!

[@leefeatherston7014]

good video 👍 thanks again my dad now's it he retired from IPL power company 33 years very nice setup

[@Ultimatereloader]

Lee Featherston thanks Lee!

[@riptide6161]

Excellent explanation of the basics of 3 Phase Power. However, I have to agree with previous commenters regarding a range of issues (close to live wires, color coding, etc.). You obviously know what you're doing, but some folks may think they could do this. I met a guy 3 decades ago who thought he knew enough. His two missing fingers elicited my "interest". He showed me the scars across his arm and chest from the shock he got from a panel. It disintegrated his two fingers, scarred him for life, and put him in the hospital. My comment is aimed at those who are not WELL educated about working with high voltage electricity. It can kill you.

[@nilescoyote4829]

Anyone else getting the jitters watching Gavin touching the wires?

[@talon0863]

Yes. that was irritating me. It's like he trying to teach how to get brain damage and cardiac arrest therapy for the DIYer.

[@Ultimatereloader]

Hey guys- you can’t get shocked from touching wire insulation :)

[@chrismccotter5351]

Treat every wire as if it is loaded. :) I've been bit by 240 though cracks in the insulation. You'll only touch a wire once after you've been bit.

[@atomicfsn22]

I got bit through a spark plug wire that had bad insulation. That hurt like hell not sure what the voltage from an ignition coil is. My damn mechanic kept telling me it didn't need a tune-up till I told him to touch the cylinder 4 wire lol.

[@bluehornet6752]

@@Ultimatereloader Heh...that assumes that the insulation hasn't been broken when you (or someone) pulled it through conduit. So with all due respect, I think you're making an assumption that may be based upon a false premise. (I've seen a mill electrician get nailed by 480v, just by touching the insulation...I was standing right next to him.)

[@geckoproductions4128]

Gavin your chalk talk primer on single phase and three phase is exactly right on....at least the way I learned it in tech school in 1971. I do wish you would consider doing me one favor though? PLEASE don't hold on to the breaker box, water pipe, or some other good ground with one hand while you are contacting wires with a finger of the other hand. If an accident occurred, the max current would surge directly through you chest and heart, likely killing you. When we were working around BIG power down at NASA in Houston the safety inspector would often make us work with one hand in our pocket until we were sure the circuit was dead. Again best primer on power I've see. BTW: the multiplier to convert from peak to rms is 0.707 and the other way is 1.414

[@hotpipe2113]

Enjoyed the video, looking forward to the series, thanks.

[@Ultimatereloader]

hotpipe2113 Good deal- I’m having fun with it!

[@davidgoldberg]

I was wondering how that works, thanks for the explanation!

[@Ultimatereloader]

You are welcome, glad it was helpful!

[@darthcollosus]

I’m an electrician by trade and there is def some serious issues with your installation and I hope no one uses this as a template. But I think you did a decent job explaining what’s going on with single phase and three phase power.

[@andrewmacneillam]

Parallel paths to ground from sub panel 💩

[@MasterTheNEC]

Also...the use of the green insulated conductor in your three phase panel is a violation of 250.119. One thing is working but minimum code safety standards must always be followed my friend.

[@ChrisUhlik]

One thing you glossed over is that rotary 3-phase convertors that use an idler motor as a rotary transformer do not produce 120 degree phased power. They synthesize a third leg which is +/-90 degrees to the two standard 120v legs which are 180 degrees to each other. So there are 3 sine waves, but they are not equally spaced. It still "works" but technically you should derate the motors driven by this because the magnetic fields do not produce the design torque as they are not properly aligned with the physical windings in the motor, those being actually 120 degrees apart. Very roughly speaking, you can think of the magnetic fields as being about 30 degrees away from their perfect positions, so you get something like cos(30 deg) or 87% of the design torque. Close enough, especially for hobby work. The phase-to-phase voltages are all about 240v, but the phase-to-ground voltages are something like 120, 120, and 250. Go and check if you don't believe me. An alternative is a single phase motor driving a 3 phase motor where the input phases are not directly connected to the output. This works for small convertors but large, single phase motors (like >10hp) aren't available. And you lose some efficiency this way too, so while the phases are well aligned, they are weaker. The main consideration you should take is that some machines have a CNC computer or other electronics that are powered from just one of the input phases. You should make sure that lead is connected to one of the "real" input phases rather than the synthesized leg. Because the synthesized leg is much higher voltage (relative to ground or neutral) than it would be in a conventional 3-phase system. I've been told this can damage computers, though I've never had a problem. Still, I'm careful with this. For example, on my surface grinder, I wired the 120v magnetic chuck to the L1 phase and not to the L3 (synthesized) phase.

[@byronmill]

Chris, excellent comments! I was hoping someone would bring this up in the comments. He may not be glossing over these facts, he likely just does not know them. I just shake my head when I see all these people commenting about how they are getting "pure sine wave three phase power"out of their rotary phase converter. It seems especially bad in the machining discussion boards and Facebook groups. They clearly have very limited understanding of what their rotary phase converter is doing. I would have a minor challenge to your comments regarding the phase angle of that third "synthesized" leg. The capacitors used in the rotary phase converter do help to shift that phase a little bit closer, though there is still a significant difference in the angle. Some higher-end rotary phase add some additional components and digital manipulation to bring those phases closer together, though never perfect, and some add components for electronic voltage control to address the voltage to ground issue that you brought up regarding that third leg. But the reality is very few rotary phase converters in operation have any of those additional components and features. In my opinion rotary phase converter manufacturers are not being honest with their descriptions of their product.

[@imkindofabigdeal4308]

@@byronmill Is this true with the electronic contols and power corretion in the AR control section? Sure seems like AR is addressing that from their product marketing but reality may be different. The AD and ADX lines specifically call that out. Thoughts?

[@sthier24]

Excellent explanation! Well done

[@Ultimatereloader]

sthier24 Thanks!!!

[@jasonrad9332]

Great explanation!

[@malcolmridings1175]

Gavin thank you for the video, however not everyone takes Trig in high school, I did learn the difference between the (two) and I will most likely watch it again, so that it sinks in. I also learned the new to me... the term torque ripple.

[@ronbianca1975]

Hi Gavin, look forward to see the 5 hp lathe running. Ron

[@hardware4200]

I thought I understood 3 phase, I didn't, now I do. However that panel wiring is not standard color code for 3 phase, at least I don't think it is. That Green is normally a protective ground, and you would have a red, black, and blue. Regardless, still a great presenation.

[@slyspy9819]

Hey Gavin great job but remember COLORS Matter , Identifying what's hot and what's not is critical the COLORS of the wire determine their function in the circuit . You MUST get that right ! What you've displayed here (12;30 ) scares me that's why I test all circuits I'm working on if the job is new to me and until I decide that the wiring is correct with respect to grounding and polarity I always proceed with caution

[@CapnBubbaa]

Great instructional video!!

[@williambrown8683]

Great video....makes it very understandable....Thanks

[@GrngulaMC]

Really good video, just one question. Shouldn't neutral be separate from the ground in the sub panel? Best regards

[@buggsy5]

It is required to be separate in subpanels by code in the USA

[@kevfinsed]

Clear and concise, thank you.

[@paulprecht9786]

I'd like to see a drawing of how the rotary phase convertor squeezes in the L3 when L1 and L2 from a single phase output and phase convertor output are still 180 degrees out of phase.

[@Ultimatereloader]

Math is coming! It's a function of the fact that potentials between poles are what the effective voltages, not in reference to neutral, etc. The end result is perfect 120 degree phasing if you look from L1 --> L2, L2 --> L3, L3 --> L1, etc. It's a math trick, but the motors/appliances don't know the difference :)

[@patrickthompson389]

This is a solid tutorial. Cheers.

[@Ultimatereloader]

Thanks Patrick!

[@patrickthompson389]

Cheers Gavin. Sometimes I get a little frustrated with the manufacturer favouritism in your sponsored reviews( which should be called advertisements, not reviews), but then you knock it out of the park with a video like this. Really; this and those numerous like it that you've shot and produced, should earn you an honorary teaching degree, and your sponsors/suppliers should be so grateful to have such an astute and comprehensive presentation of their products, their capabilities, and their safe operation. Keep up the amazing work.

[@jhawksfarm]

Hey Gavin, just get some red and brown tape or tape them all black and that will take care of the white and green wires. Green should always be ground and white should always be neutral. I wont get into never using the green wire for a conductor. That's my two cents, I really enjoy your videos.

[@danh5150]

Another excellent video, sir! Very concise explanation. Just a minor safety note (and I saw below some others had already commented about safety as well); it's good practice to NEVER wear metal jewelry (i.e.-wedding bands) or a wristwatch when working around electricity. You seem like a cool dude. I'm sure your wife wants to keep you around as long as possible! ;o)

[@boober7270]

Can I call dibs on a barrel when you start turning them lol.

[@Ultimatereloader]

:)

[@paulshepherd7457]

How significant of a problem is torque ripple on a lathe? I believe you wired your PM1440GT to 220V single phase.

[@colsoncustoms8994]

Awesome, thanks for the info.

[@Ultimatereloader]

Colson Customs You are welcome...

[@franklinhernandez7387]

Thank you!!!!!

[@Korey47]

*8:06* Box: stop yelling at me! This dude: Shut up and let me explain

[@TheMulk777]

Very helpful. Thanks!

[@NES50]

Sorry, but a second phase is 120 degrees shift to first one(360/3=120). Tge voltage will be lower as just a difference between two phases. At least so it in Europe.

[@jerrymont2595]

Hey, you still have your old machine I see

[@benwagner4770]

Great explanation! Thanks

[@Ultimatereloader]

Thanks Ben, and you are welcome!

[@upyours6000]

Theoretical can i run a machine that is design for 240v single phase on a 3 phase. The voltage would still be 240 its just more consistent. Im just trying to understand basic electric engineering. Thanks

[@buggsy5]

You could, but with a lot of torque ripple and reduced power - since the voltage across two 3 phase legs is 208 volts, not 240 volts.

[@seandecourcy7297]

Wow! Some super dangerous wiring in your installation! I hope one of your connections at the lathe doesn't loosen over time and contact the lathe case because you're dead! Bond wires going to the neutral bar.....another major mistake! Lots of wiring issues here.

[@talon0863]

Ummm are 3 phase lines typically white and green? And by the way if you get your fingers any closer it might blow off a finger nail.

[@Ultimatereloader]

Stay tuned for the install video where I label the wires :) (rural location, didn't have much choice on color). You can't get shocked touching wire insulation :)

[@paulwatterson5992]

Good info ! How do you get 3 phase power into a residence? Or do you generate 3 phase power from single phase?

[@oriongaby]

The reason 3-phase power even exists is because industrial power generators actually generate 3-phase power and that is converted to single-phase because it's cheaper and easier to transmit (2 vs 3 lines), it's also easier to balance a current load across two phases when you're only using single-phase electric equipment. These are some of the reasons why you DON'T get 3-phase power delivered to residential areas, but it's the most common form of power delivery in industrial areas and somewhat common around commercial areas.

[@OU81TWO]

12:37 "I'm just gonna go ahead and turn that on. Now we have live power..." (starts putting fingers into the panel) Dude wtf??

[@Ultimatereloader]

Contrary to what some people think, you can't get shocked by touching the plastic part of a circuit breaker :)

[@DavidHerscher]

@dliguori25 yeah no, he was SUPER close. especially when pointing out the 3 contacts, like, he almost put his fingers on those contacts. Gavin def knows what he's talking about, but maybe not showing quite enough respect for that "little" panel when poking around in there. I would argue that there was no justifiable reason to energize the panel in the first place and the safer, and better, option would have been to leave it cold. Still, great vid, just be careful man! We want to see more great machining videos, not unintentional BBQ videos... XD

[@snteevveetns]

I knew I liked you for some reason, then you start drawing on the board left handed!! Yesssss lefties unite! LoL

[@monk4786]

No equipment ground to the lathe ? Hmmm

[@Ultimatereloader]

Stump Busters Strange, huh? Different thought process in the 1940s :)

[@Ultimatereloader]

I plan to add ground to the lathe when I finish the initial install and renovation.

[@Towert7]

Holy shit! I hope that circuit breaker wasn't energized when you were touching it! God dam, that's a quick way to end your life, doing what you just did. NEVER "GRAB" AC.

[@Ultimatereloader]

towert7 Just as an FYI- breakers won’t kill you if you touch them. They are switches- designed to be touched when you switch them on and off :) - unless you are watching Macgyver.

[@tedtedness184]

The last box was done by a hack and not an electrician. The wire color scheme is not used and off. No bond to the the panel. You should of used tape to call out your wire. Black, Red, Blue, and in that order. If the first box was a sub panel it's wrong too. Hows your neutral feedback doing. No marked wire and you have full romex wire inside the box. If people are using your equipment do them and yourself a favor, get your boxes up to code. We can all see you did not permit your work, it never would be approved.

[@businessandpoliticsinswede3138]

I can't stand the sound of the pen scratching the board.

[@springtimeplumbing6240]

Keep your damn fingers out of the panel!! Bad, bad example. If you need to point something out, use an nonconductive pointer.