Three-Phase Power Explained 

Wow good testimony. Can you mentor someone? I am an electrical engineer

@@theachebes5724 Not on 60 Hz AC power. My AC power/motors experience ended with college. My experience is in RF-- its propagation, and also loss/gain calculations for hight power radio and TV stations. Did several 5 MW ERP/60 to 80 kW TPO analog TV designs, but with digital the maximum allowable ERP is just 1 MW, so TPO's are typically in the 40 to 50 kW range. Still, it's 6-inch rigid coax line to handle the power. No more waveguide transmission lines, given that UHF TV now stops at Channel 36 (605 MHz) instead of Channel 69 (803 MHz).

i'm ee undergrad student, can i get your contact?

most stupid explanation

I understand all that 100%. What I can't understand is how is there not live power on the neutral?

@@fuckjewtube69 here’s my understanding, take it for educational purposes, not instructional or safety purposes: the neutral wire DOES carry current, specifically the returning current through the home’s loads (ie. lightbulbs, tv’s, appliances, etc…). The neutral wires coming from the loads in a home’s breaker panel are tied to ground and the neutral wire coming from the secondary transformer is also tied to ground at the pole. Because neutrals are tied to ground, the Voltage potential from the neutral wire to ground is minimal. Power can be calculated by multiplying Voltage by the current (Amps). If there is practically 0 volts on a wire, then the power is going to be ~0 as well. **That is why it is possible for a person standing on the ground to touch a home’s bare neutral wire without getting shocked. It is also why the neutral wire coming from the pole transformer into a home is a bare conductor (no insulation). **If there are situations like lost/disconnected neutrals or grounds; ground faults where limbs of a tree touch bare high voltage wires; etc… then this statement may not always be true, it may be possible to get shocked. In summary, it’s about completing a path for current to flow, but also how much force (aka Voltage) behind the current flow; and it depends on exactly what two points in the electrical loop/circuit are being touched/connected in order to cause current to flow.

Is there a Grammer error? I have was??? Think you for your advice

Say that again in English

@@enyakang6950 Yes. He meant "I was only wondering about 3 phase for about 25 years ..." but another way of saying it would be "I've only been wondering about ...". So he probably started one way then switched to the other without noticing. As you probably noticed, the "only" is ironic, because 25 years is really a very long time to wonder about something. Only been wondering for 25 years! I've been wondering for longer, as I'm probably older and it's a long time since I first heard the term.

Absolutely, good point. I saw the same wrong explanation in other videos about AC...

Boring!

Kevin Butler Woow. This is absolutely superb explanation. But why have you switched off the save button

How do I turn the save button on?

4:18 Why did the electrons stop in lines 1 and 2 even with the magnet rotating?

@@mikeymcmikeface5599 i dont think it does becuz only one line will ever be perpendicular to the magnet every time it rotates while the other two will be parrallel to the magnet

We don't use 2 phase. We use single phase, with 2 lines 180° apart.

Common misnomer.

True (sorta). It is actually 2 phases, but they are phase locked 180 degrees apart and we have access to the 2 hots and that center tap. So in reality, it is a combination of both single and double phase. Imagine if someone had 2 lines each 120V and each having a neutral center tapped to the same transformer's secondary winding. Next imagine if they could put say a 45 degree delay in one of those lines. Would it then still be single phase or 2 phase? If 2 phase, then you are saying that when 2 lines are 180 degrees apart it is single phase but is it really? Some people would agree and some would disagree.

Brightwriter also you can reverse direction on it

If the starter winding is out or the centrifugal switch is non-functional, you can hand-spin a single-phase motor and it will run both ways. We had a bench grinder with a failed "cent" switch that would have sent power to the start winding. I put a momentary-contact switch in the start circuit, and then at the moment I would turn on the grinder I would push the added switch until it got up to speed, and then let that switch go and all was well! It we didn't hit that switch the motor would howl and not turn. If I hand-spun the grinder wheel backward and then did the other steps before it stopped drifting backward it would run in the wrong direction! Also, if I am not mistaken, the 3-pase motor was invented first, and it was supposedly a battle to make an effective single-phase motor after that.

Engineering Mindset is perhaps the best channel for this kind of stuff. This is also a good explanation.

S

Did you ride dinosaurs to school?

ΑΡΣΕΝΗΚΟΛΗΘΗΛΑ ΠΡΟΣΟΧΗ ΤΗΣ ΔΙΑΣΤΑΡΟΣΗΣ

you don't want a lay person without the background working on 3 phase, lol, lmfao, pmsl and ha ha. not unless you have a good Hoover to clean up the little pile of dust that will be left where he once stood 💥😵🌬💨👋

Would have been better without the crappy distracting music!

I gave up at 1:44. He doesn't have a clue how fluctuating magnetic fields induce an electric current.

@@-danR could you explain what's wrong? I'm not be facetious, I'd genuinely like to know what was wrong.

Two is clean

Lenz law, basic electromagnetism.

The waveforms at 4:50 and 5:25 look totally different. Why is the first one asymmetrical, as if the waves are grouped together? Just a crappy animation?

9 out of 10 comments are praising this video's claptrap. Unbelievable.

I was thinking the same thing. Anyways, most modern three phase industrial motors are induction and controlled by some kind of VFD.

@@joshbachman7706 indeed Industrial inverter drives are brilliant for matching speed matching ramps or current limit I have fitted thousands from 0.05kW up to 3000kW fun days.

Scott J Electrons do not necessarily need a wire to move about. Electrostatic charge is one example. Electron beam is another. Old CRT TVs used the steered electron beam for half a century. There are scan converters that still use them today. Then there is always radio. Electrons are not pushed anywhere. They are lured to an electron depleted field through what ever means they can. Open space requires very high potential levels, metal conductors very little. This is a small sample of what you left out of your educated reply.

Bryan St.Martin, Although everything you've said is true, it's irrelevant to the understanding of 3-phase power and the functioning of electric motors. The current in an antenna is negligible compared to the current in an electric motor, generator, or transformer where the electrical circuit is complete. I do agree with Scott J that the pictures in this video demonstrating the magnet and the current in the wire are a bit wonky. The video makes it appear that electrons are attracted to the north pole of a magnet, and repelled from the south pole. If this were true, we could obtain free energy by using magnets instead of batteries. Rather it's the moving magnetic field that induces a force on the electrons. Neither the pictures, nor the explanation in this video explain this, and in fact imply that this is not true. For someone who doesn't understand these things and who is trying to learn, this is going to cause a lot of confusion.

There's a reason he said at the beginning of the video that this video requires an understanding of how AC power works, and that if you don't have such an understanding you should watch the video on AC power first. You're criticising this video for something that was explicitly stated would not be in the video. It's like someone saying they are going to show you how to cook pasta, and you're complaining that they skipped over how stovetops work.

Jeffery Wells, I'm criticizing the video because what he's showing is not only confusing, it's wrong. The north pole of a magnet does NOT attract electrons. The wires have to be moving perpendicular to the magnetic flux lines in order for there to be a force on the electrons. The wire has to be oriented so that force is in a direction that causes current to travel through the wire. What is shown in this video will cause no current at all.

Scott, I'm the creator of the video. If you watch the first video, you'll see and hear where I say that while I SHOULD show a loop of wire (per your comment) BUT in order to keep things simple, I will only show half. The issues with creating these types of 7-10 minute videos are: what do I include and what do i cut; what analogies do I use to explain the basic concepts which are rarely well explained. I decided that showing a looping wire would be harder to visualize and animate. It would also open more esoteric topics. My goal was to explain the topic to people who didn't understand 3 phase.

The _radical symbol_ *√* is NOT an "r"-it is a mathematic symbol. *√3* means _the square root of 3._ Or, _3 to the power of_ ½. *√3 ≈ 1.7320508075688772935274463415059*

Because there was/is a common configuration that is 120V to ground on 2 legs with a stinger leg which is 208V to ground. They are 240 delta with a center grounded winding, quite common where I live. Your company probably could have bought a transformer.

You are correct, but in most cases the generator is moved with burned fuel.

ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-HqZtptHnC2I.html

yeah.. that video doesn't explain anything, because the numbers seem to be chosen arbitrarily. so.. no real background there. again: after 3 phase power the next possible number of phases would have been 5 for the reason of a steady power output. but it can be explained quite easy why 3 phases were the way to go - there is no need for a 4 minute long explaination.

Hace mas de 100 años, en los inicios de la electricidad, se probaron sistemas de varias fases, pero el sistema que venció a los demás fué el trifásico.

Here's a simple answer - the cost of copper. The detailed answer is a very technical analysis of cost of additional copper for each phase versus the increased "performance" of more phases.

the need for an alternating current with constant power output (and not any sin-wave power!) came from electric locomotives. they would slip with a power peak coming for example from a single-phase sin-wave power. when slipping, the friction reduces a lot limiting the capibilities of it! but with a constant power output the trains could be built smaller and more efficient. and again: 3 phases, 5 phases, 6 phases, 7, 9, 10, 11, 12, 13, 14, 15, ..(any uneven and multiples of those uneven numbers mentioned before) have a constant power output over time. and obviously when they all do the trick why use more than 3 phases? wouldn't have made sense in any way (yes, cost, but also complexicity). always think of the histrory of the technical system you have in front of you and electricity wasn't always for wide public use! then tesla and westinghouse had their stupid fight over AC vs DC is was already decided in europe to use 3 phase AC. that's what noone from the north-american continent seems to know and maybe they just don't want to know..?

+Jorge Cervantes - Yes, certainly it's possible but it's not a common scheme, at least in America. 220-240 volts 3 phase *is* common in Europe and most other parts of the world. The closest scheme in America to your question is the 277/480 volt 3 phase system used in factories and large installations.

roy yung- great point but hey at the end its all in "P" ie power

You can use ohms law if the load is pure resistive and power factor is 1

Id be one of those people but it's hard to avoid the brainwashing terminology of the ac power fans. Hot neutral and earth? Isn't it power, ground, and redundant ground? Also wouldn't a pulsing DC run a transformer just the same? I mean unless ignition coils are some sort of black magic.

There is always a real component (I.e watts) in power calculation of AC circuits. Apparent power includes the real and imaginary vectors in the calculation and units is VA. Most electricians widely misuse these units and how to calculate them.