5th year union electrician apprentice here. You are very good at explaining this. Much better than the ac theory teacher i had at the time. This is great! Thank you
hey bud, I've been a Hydro One station electrician for a little over 10 years now. I like your videos because as time goes on its good to get a refresher. We deal with mostly delta in from our 115kv-500kv delta system to 27.6kv wye system out so we see a wide variaty of electrical systems. We work with alot of types of circuit breakers from Air Blast to Oil and SF6. if you want some sweet switch arcing videos and transformer fire pictures I have a ton.
I dont mean to be off topic but does anyone know a method to log back into an Instagram account?? I somehow lost my account password. I appreciate any assistance you can offer me
@Milo Maxim I really appreciate your reply. I found the site through google and im waiting for the hacking stuff atm. Takes quite some time so I will reply here later when my account password hopefully is recovered.
To get an idea of phase vectoring and voltage, draw a circle with a 1 inch radius. Draw the first line straight up north, then another line 120 degrees away from it. Measure the distance from the end of each line (I think that's called hypotenuse). You'll find it to be 1.73 inches. So 120V times 1.73 is 208V. This can be applied to any degree of phase variance. Or you can use trigonometry. If you look at residential service (single phase center tapped with 180 degree phase variance) and apply the same diagram, you'll have 1 line straight north and 1 south. The distance is 2 inches. Voltage times 2, or hot to hot, makes it obvious why your stove gets 240V. And like he said about Wye, this is what runs down your street on the hydro poles. If it's the old style horizontal cross arm on the pole, just look for the odd colored or odd sized insulator and that's neutral. They're getting away from the horizontal cross arm these days because believe it or not, the bolt holding it on is a convergence point for field induction that could heat up that bolt.
The reason for the bolt heating up is because the insulators holding the conductors are leaking currents due to contamination. The leaking currents are trying to get back to the source so they travel through the wood arm to ground and or other conductors that are contaminated. The currents over time will heat up the materials it travels on and wood can dissipate this heat very well. Metal i.e bolts doesn’t dissipate heat it actually accumulates heat and ends up starting the wood around it on fire. To keep this from happening we bond all metal attached to insulators so as to give a path for this current to flow on. This prevents pole fires.
@7:45. ..there are wye/delta starters and motors and there are Soft Starts. They are not the same thing. They both employ reduced voltage technique but a wye/delta start starts at 58% voltage and a soft start is a solid state electronic device that uses SCRs to go from 0 to 100 % applied voltage.
Just to make sure I've got it straight; With a Wye service connection, Line 1 to Line 2, Line 2 to Line 3, Line 3 to Line 1 would all be 208? Delta would be Line to Line 240V between all three, with phase A Line to Neutral at 120V, phase B Line to Neutral should be 208V, phase C Line to Neutral 120V. Or is there no Neutral at all in Delta system and electchicken told me wrong. In my case, there appears to be ONLY be 3 insulated wires and bare wire from the utility transformer going to utility meter panel. Panel has a bonding wire to ground to create the neutral if I remember correctly, making this Delta system. Es correcto?
I was like no, it would be 240 if you used plus signs, but since the coils are out of phase; we are forced to use vectors. That is how we come up with 208.
Hi I'm Jon from the UK, I am an electrical controls systems engineer with over 30 years behind me now.There is a common misconception that both Star & Delta configured motors produce the same amount of torque and motor power. The basic problem arises when the teaching staff are competent but lack personal experience in that when you look at the equation and the only difference is the Line and Phase voltage difference and don't realise that when starting a motor the FLC is multiplied by about 4 for star connection and a minimum of 6 x FLC for Delta.However this is only the starting current so for a given load the reduced starting current of star saves on cable installation costs but compromises the long term operational cost of the plant in that the motor current of Delta is far lower than the same motor connected in Star.The selection of motor starter type is dependant upon many influences including the type of operational parameters:Common Standard Motor Starters For 3 phase cage types are:DOL = Direct On LineStar/Delta = Main Star & DeltaSoft StartInverterPole Changing MotorsIt should be noted that a good rule of thumb for Variable Speed Motors supplied from an inverter its supply frequencySo: 50Hz +/- 25% = (37.5 - 62.5Hz) ((60Hz +/- 25% = (45 - 75Hz)) if the motor is expected to operate outside this range then independent forced cooling units mounted to the motors is recommended. This is due to the motor cooling necessary because of the increased thermal load of running the motor outside its designed operation window.The use of a pole changing motors together with an inverter can be significant torque boost at starting load in that the motor say for example was an 8/4 pole motor then the motor can start in 8 pole 750 rpm double torque then switch over to a 4 pole motor at normal torque at 1500 rpm, then add on the torque boost from the inverter and the torque can easily be doubled again.
Your house only gets one phase, stepped down by a somewhat special transformer near you. This video is not relevant to your question about voltages. You get your two voltages from your single phase, local, center grounded transformer. From that center tap to each of the other two leads, you will get your 120VAC, from the ends of the secondary, its 240VAC. Its all about that center tap on the secondary of your local transformer. In the US, your wiring will be white for that center tap. This is neutral. Whoever sets up your breaker box will pick a side and it will be 120VAC or hot and it will be a black wire. The other side is usually wired red and it is reserved to use against the black to provide power to water heaters, stoves and other 240VAC services.
@@mscottmiracle1396 You would also use the red wire to feed 120v load that keeps the panel and transformer balanced. Both black and red wires feed 240v loads.
A "Wild Lag" would be the term for that unique 277 v different voltage winding on the rare type of 3 phase 240 Delta secondary X-former designed specifically for boost assisting the start rev of a industrial large motor(s) under weighted load like with commercial sludge pumps or the sawmill's saw blade drive motor. These are rare unless in an industry and prone to human factors when failing to recognize this unique X-former output. You are correct to lable that Wild Lag the color Orange as only that reveals to the eye to stay away when load balancing and always connect the ABC order perfect the first time with any Wild Lag motor type or you will smoke it baby and no one to blame for your bad guess work.
Good explanation! If I have two transformers (1&2) connected to each other; should the secondary connection of the main transformer (1) be the same configuration of the primary of the second transformer (2) ? Eg. should the connection be delta-delta ?
I don’t know that I have ever seen a delta at 120 volts. All I’ve seen was either 240 or 480. The 240 with one transformer center tapped for 120 is quite common for commercial, so also is straight 480 for industrial, with 120 coming off a separate 480 to 240/120 transformer.
This grid service type does exist as a 240 Delta (Not WYE), but with a center point tap (bonded to ground as our neutral buss between phase A and phase C often termed as a "Stinger". So then you get 240v between A&B, B&C, C&A, But then also can power standard receptacles that use a 120/240 Dual or "Split single" phase between A&C. For this one though, you must have a conjoined subpanel fed from the 3Ph MDP so that it can bond the center tapped Neutral to service ground point in that first MDP enclosure as close as possible to the secondary of the service X-Former. An electrician may be able to give a more current code explanation then me as I only have DC solar knowledge from my many installs with SMA inverter types that support the 240/120 Delta configurations but never came across one in USA service types. I'm eager to work with this in a hybrid router system since it would be superior if average use models are load balanced properly with our intermittent grids "Rolling Blackouts" reality coming to your theaters soon predictably.
American Military generators use the Wye and Delta configurations, however, we use them in parallel and series connections using six independent coils. In a parallel Wye, we can get 120 single phase and 208 three phase, only. Our 5 and 10KW generators use both Wye and Delta configurations; parallel delta 120VAC single phase Only, series Delta 120/240VAC single phase, and parallel Wye for 120/208VAC. We can set up our 15KW through 200KW generators with either parallel and series Wye connections. The reason is for NATO power. On our parallel Wye we get the 120/208VAC and in series Wye we 240/416VAC. We also can set our generators to 50 or 60HZ. All the American Military generators have to be NATO compliant. I tell my students that when figuring the Wye three phase to take the line to neutral voltage and multiply by 1.732 for the three phase voltage (207.84). It's easier than going through the Trig computations.
Hey. Really good info here - very useful. As far as learning more about this, is there a text you can recommend on Wye and Delta 3 phase configurations? Thank You.
In Russian they call the wye a "star" and the delta a "triangle". The instructor at the trade school was not anywhere near as lucid as you, and he was hung over half the time. I wish I studied with you as the instructor.
Good overview of this. Now to expand on this just a bit....I'm looking at installing a 3 phase solar inverter. It can be configured for either Y or Delta. In this case I'm thinking I would want to go with a Y configuration, however in some respect a Delta might be better. The only draw back I see at this point would be the lack of ground in the Delta circuit. What would be your thoughts on this?
Ground and Neutral are not the same thing. Delta configurations do not have a neutral, but they can still have a ground. None of the conductors are _grounded_ in a Delta configuration. In the Star/Wye configuration, the neutral carries the imbalance of the loads of the three phases, and it is usually directly grounded. Delta configurations must utilize an indirect kind of ground. I'm no expert, but the Wye configuration always sounds easier to me to implement.
+Kurt Langeberg - I tend to agree with Jovetj. The wye configuration is probably the better way to go, especially if this inverter is going to supply AC to an occupied building, off the grid. But the choice really depends on the total application. Is the system off the grid (with batteries) or is it grid-tied? If it is grid-tied then it must be compatible with the configuration that your power company is providing you with. If it's a standalone system that is charging batteries then the choice comes down to system voltage and capacity. High voltage/lower current systems would favor the wye system, lower voltage/higher current systems would favor the delta system. It can be quite the panoply of possibilities with these things. The key is knowing everything you can about the installation.
Single phase systems provide 120/240VAC 120 phase to neutral and 240 phase to phase. The 120 degree separation on a three phase system as opposed to 180 degree separation on a single phase system is only there for smoother operation of three phase motors and such.
I may have missed it but what about how delta can run with faults and is used in the nuclear industry and some Electric arc furnaces. Also the delta-wye/wye-delta transformation would of been good. Also some per phase/3 phase analysis would be nice
+Shredxcam22 - I can't answer all your questions but as far as a delta system running with faults, there is the case of the "open delta." This is when one of the phases is taken out of circuit for any number of reasons: maintenance, replacement of a bad component, etc. It is possible to do this in a delta system because the two remaining phases will actually recreate the missing phase and allow continued power flow to the loads that were handled by that phase. Of course allowances must be made to avoid overloading those two phases since they are now doing the work of three phases. Obviously this is a big advantage for power systems and "the grid" in general.
There are times when delta is not grounded, so if a phase goes to ground there is no current flow to activate protection. There is no current flow because of no relationship between transformer and ground. It would take two faults to ground on two different phases to create a current through ground and activate protection device. This is done on purpose so you don’t shut down that circuit for one fault. This advantage is needed for production oriented business.
+Ajay G - Actually the phases and lines *are* in series in a wye system, so most certainly the currents would be the same between the two. The exception is the neutral wire, which has the three phases paralleled to it. So the current in that wire is the vector sum of the three phases. And if the three loads are equal (balanced), no current will flow through that wire. In those cases, such as three phase motors, the neutral can be eliminated.
Could you please elaborate the sequence current and voltages developed below described scenarios. A 500KVA distribution transformer with 6% Z, 11/0.44 kV, Dyn11 connections lost one HV conductor. That conductor is on floating from source side and transformer side is touching with ground having less than 3 ohm ground resistance. So how much current will be developed in healthy phases and what will be the value of zero and negative sequence current
There are a lot of videos on that already. No offense, but if you dont know the difference, then you really jumped ahead when you watched a transformer video. He expects you to know that already.
I’m trying to start learning the electrical field as I have been working in the manufacturing field as a mechanic and have been exposed to electrical systems but haven’t been learning much over the past few years as our company doesn’t want to help us advance , now I want to expand my ability and branch out , that being said how would you suggest I start learning about industrial electronics.
I’m totally confused. I have an old crescent disc sander. It has a three-quarter horse three phase motor. There are four wires coming out of the motor. Two of the wires go down to the motor starter and connect to T1 and T3. The other two wires up at the motor are connected together. So it appears that the motor is only running on Two legs. T1 and T3. How is that possible? Anybody’s help would be greatly appreciated. Thank you
The Electric Academy I went through a weird transition and have had to learn a lot. Avionics to working in a steel mill. I had to learn a ton but something are not often talked about. I plan on doing some videos eventually. I am finishing my BS electronics engineering technology which many people don't get the difference between EE and eet even tho both are ABET accredited.
You are going to need a rotary phase converter, look up americanrotary.com, or you can build one yourself. Or you can go with a VFD, just make sure that you get one that requires 240V AC single phase on the input.
am I correct that for an alternator, the W phase is preferred, for the motor the delta - in case we are talking about a system in which the alternator feeds the motor (through a battery bank)?
In a 9 lead motor at high voltage the wye and delta are connected in the same configuration. How can I determine whether it is wye connection or delta then?
can you do one more in depth about the differences of like corner grounded deltas and all the other ones. I'm an apprentice with the iec and went haven't gone over it to much in detail. probably my fault for not asking the right questions
Great video! Thank you you explain on how we obtain 120 V 208 V and 480 V but you didn’t clarify on 277. Can you please make a video on that? Thank you
480V is the phase-to-phase voltage of a 277V phase-to-neutral three phase system. The problem is inconsistent naming. We call it "120V three phase" and "480V three phase" but the first is named after the phase-to-neutral voltage and all other higher voltage systems are named after the phase-to-phase voltage. This is probably because the 120V systems are typically wired in Y configuration and higher voltages are typically in Delta configuration. In a Delta configuration, you would rarely use the phase-to-neutral voltage. But in a Y configuration the line voltage is frequently used. So the inconsistent naming convention makes sense with this logic.
The “H” is the high voltage of the transformer. The “X” is the low voltage of the transformer. “Primary “ is the the side that magnetized the transformer. Secondary is the side the load is connected to. Typically primary is feed in the “H” side and the load is feed by the “X” side. In this configuration the transformer is in step down configuration. When you feed the transformer in the “X” side then that becomes the primary side and the”H” side feeds the load becomes the secondary side. In this configuration the transformer is in a step up configuration.
On a delta connected system since there is no reference to ground what is the downside to having a wire shorted to ground. You won't notice it I assume but I assume that this will ultimately cause a problem. What would be the issue?
On these ungrounded Delta Systems there is a ground fault detection unit. The first ground fault is "free" and personnel is alerted by detection unit. It gives personnel time to find the fault without the whole system coming down. Another fault to ground on a different phase would create a phase to phase fault and that would trip main feeder breaker. These systems are used in process plants with majority motor loads.
@@ikerivers1795 so sounds like with delta if there is one fault it really doesn't matter. Only issue I can think of is that before with no fault if someone gets across a phase and ground there is no shock hazard, but once a fault occurs there would be a shock hazard if they the touched the other phase and were also grounded. Seems like a delta system is inherently safer unless there is some other aspect I am missing.
@@diyertime kind of...."shock" is the result of difference of "potential". Difference in voltage magnitudes regardless if your "grounded" or not. If you are grounded though that is an easy reference to near zero potential so whatever you touch is maximum potential difference.
@@diyertime This is a 3 wire Delta System I was describing. There are also 4 wire Delta Systems, where a grounded conductor i.e., neutral is derived from midpoint of a phase. ,
@@ikerivers1795 this gets to the heart of my question, what would be the advantage of adding this ground? Just so a fault is easily/quickly determined? Just as an fyi, I am a registered prof EE albeit most experience with computer engineering and rf electronics. I also did a stint for an electric utility. So if you need to be more technical its ok.
He should review his videos and get the errors out before posting them. A tutorial should not contain elementary errors because they just confuse people who are trying to learn something.
Hey! I just found your channel just now. At this time in my life, i suddenly have electricity on the brain. And this is like intellectual Kraft caramels to me; cant get enough. Here's one for you, I work on 115v ac machinery that has REVERSIBLE ac motors. I would like to construct something whereby i could bench test them, as in, hook them up to power and run them outside the devices they are from so as to evaluate their condition overall. Do you have a video on that sort of thing? or could i trouble you for any links to such that you might be aware of?
How can all three phases come together after the load being 120 degrees out of phase and nothing blow up. But if you cross phases before a load its a disaster?
+Caleb LeMay - If you are referring to how the three phases in a delta system can form a closed loop without blowing up, the answer lies in the fact that the VECTOR sum of the three voltages is always zero. So no current actually flows *around* the closed loop. You can actually see this by opening one corner of the delta and read zero volts or very close to it between the two leads. Put another way, it can be shown that the vector sum of the voltage of any two phases is always equal to the voltage of the third phase--again proving that no current will flow around the closed delta. This is one of the few cases where out of phase voltage sources can be directly cross-connected without blowing up. Chalk it up to the craziness of the math.
+Caleb LeMay - You need to find a good book on AC electricity. To start with, the type of load makes no difference in this point -- inductive, capacitive or resistive. The type of load will have a direct relationship on the phase angle between the voltage and current in the three lines going to the load but we are not talking about that here. As for vectors, think about the numbers that you see every day: the amounts you add and subtract in your checkbook, the prices of the groceries on your cash register receipt, all the different charges and credits you see on a utility bill, etc. All of these examples, in fact most numbers you work with in everyday life are examples of *scalar* quantities, numbers that solely represent an amount. Voltage, current and resistance in DC circuits are good examples of scalar quantities in electricity. Working with AC thrown in one more thing: *direction*. This makes up a vector. It denotes both magnitude (a scalar quantity) and direction (phase angle). Like other numbers, vectors can be written out like any other number -- with special notation so that you know it's a vector -- or graphically. This last method is usually the easier one to understand. For our purposes, perhaps this analogy will help you grasp the principle of the delta. Imagine two 1.5 volt dry cells hooked together in series, but connected say, negative to negative instead of the usual negative to positive. Now, run a lead from the shared negative to two light bulbs connected together (not in series). Now, connect a lead from the positive terminal of each dry cell to the free terminal of each lightbulb. What do we get? Both lightbulbs illuminated. What we have are two independent circuits consisting of a dry cell (voltage source) and a lightbulb (load). With this configuration you can disconnect each lightbulb but the other one will stay illuminated despite appearing to be in series. Now, measure the voltages around the circuit. What do we have? 1.5 volts across each bulb, so we know we have two power sources driving their individual loads. But what do we get if we read the voltage from one positive terminal to the other? Answer: zero volts or very close to it. In other words, the voltage of one dry cell has cancelled out the voltage of the other without affecting the operation of the circuit or causing damage to either dry cell. This, in a more complicated way is what is happening with the closed delta loop. Some suggested things to look up: polar and rectangular vectors, the trigonometric functions (sine, cosine and tangent), and if you're really brave, the trig formulas for the sum of two angles (example: sine of angle A + angle B). Mastering this formula and plugging in the right numbers is the key to proving mathematically that no current will flow around a closed delta. Hope all this points you in the right direction (pun intended. LOL!)
Caleb, I assume you are looking at the centre of the Y configuration. Think of it as if you had three single phase motors each plugged into a separate plug with a unique hot phase of supply. Let's call them your blender, coffee grinder, and food processor. Each kitchen appliance has a two-wire connection of a hot phase supply and neutral return. Why is the return neutral? Reducing to utter basics, because the voltage has been "used up" (as power output of the motor) across the inductive coil of its motor. So the neutral has zero voltage and can be connected to ground. So if you were to strip bare the neutral wires on your blender and grinder, and touch the neutrals together, there would be no problem, because there is no net voltage between them. The same applies inside a three-phase motor. The voltage has been "used up" across each coil. Since the voltages are 120 degrees out of phase with each other, the voltage is "used up" at slightly different times each cycle but each phase has a neutral (zero volt) side for the same reason a single phase motor does. To save wiring, the motor just ties those neutrals together into a singe wire.
The grounded delta can be very dangerous if you don't know the system. Your wiggy will show no voltage from ground to that leg and you'd assume that there's a problem.
5th year union electrician apprentice here. You are very good at explaining this. Much better than the ac theory teacher i had at the time. This is great! Thank you
hey bud, I've been a Hydro One station electrician for a little over 10 years now. I like your videos because as time goes on its good to get a refresher. We deal with mostly delta in from our 115kv-500kv delta system to 27.6kv wye system out so we see a wide variaty of electrical systems. We work with alot of types of circuit breakers from Air Blast to Oil and SF6. if you want some sweet switch arcing videos and transformer fire pictures I have a ton.
lets see em!
I dont mean to be off topic but does anyone know a method to log back into an Instagram account??
I somehow lost my account password. I appreciate any assistance you can offer me
@Weston Zayd Instablaster :)
@Milo Maxim I really appreciate your reply. I found the site through google and im waiting for the hacking stuff atm.
Takes quite some time so I will reply here later when my account password hopefully is recovered.
@Milo Maxim it worked and I now got access to my account again. I am so happy!
Thank you so much you really help me out !
Amazing!! You are making complicated things way more easier to digest. Thank you for your knowledge sharing and wish you all the best.
To get an idea of phase vectoring and voltage, draw a circle with a 1 inch radius. Draw the first line straight up north, then another line 120 degrees away from it. Measure the distance from the end of each line (I think that's called hypotenuse). You'll find it to be 1.73 inches. So 120V times 1.73 is 208V. This can be applied to any degree of phase variance. Or you can use trigonometry. If you look at residential service (single phase center tapped with 180 degree phase variance) and apply the same diagram, you'll have 1 line straight north and 1 south. The distance is 2 inches. Voltage times 2, or hot to hot, makes it obvious why your stove gets 240V. And like he said about Wye, this is what runs down your street on the hydro poles. If it's the old style horizontal cross arm on the pole, just look for the odd colored or odd sized insulator and that's neutral. They're getting away from the horizontal cross arm these days because believe it or not, the bolt holding it on is a convergence point for field induction that could heat up that bolt.
The reason for the bolt heating up is because the insulators holding the conductors are leaking currents due to contamination. The leaking currents are trying to get back to the source so they travel through the wood arm to ground and or other conductors that are contaminated. The currents over time will heat up the materials it travels on and wood can dissipate this heat very well. Metal i.e bolts doesn’t dissipate heat it actually accumulates heat and ends up starting the wood around it on fire. To keep this from happening we bond all metal attached to insulators so as to give a path for this current to flow on. This prevents pole fires.
@7:45. ..there are wye/delta starters and motors and there are Soft Starts. They are not the same thing. They both employ reduced voltage technique but a wye/delta start starts at 58% voltage and a soft start is a solid state electronic device that uses SCRs to go from 0 to 100 % applied voltage.
A refresher for electrical enthusiast. Thanks for posting this. God bless.
Phase to phase on a Wye system would never be 120 volts that would be from line to neutral only
I'm glad you clarified that...It was f**king with my head.
Just to make sure I've got it straight; With a Wye service connection, Line 1 to Line 2, Line 2 to Line 3, Line 3 to Line 1 would all be 208? Delta would be Line to Line 240V between all three, with phase A Line to Neutral at 120V, phase B Line to Neutral should be 208V, phase C Line to Neutral 120V. Or is there no Neutral at all in Delta system and electchicken told me wrong. In my case, there appears to be ONLY be 3 insulated wires and bare wire from the utility transformer going to utility meter panel. Panel has a bonding wire to ground to create the neutral if I remember correctly, making this Delta system. Es correcto?
Me too
I was like no, it would be 240 if you used plus signs, but since the coils are out of phase; we are forced to use vectors. That is how we come up with 208.
@@phfedawg We are not forced to use vectors. It is physics. It is just how nature works. It is vector quantity phenomenon.
Hi I'm Jon from the UK, I am an electrical controls systems engineer with over 30 years behind me now.There is a common misconception that both Star & Delta configured motors produce the same amount of torque and motor power. The basic problem arises when the teaching staff are competent but lack personal experience in that when you look at the equation and the only difference is the Line and Phase voltage difference and don't realise that when starting a motor the FLC is multiplied by about 4 for star connection and a minimum of 6 x FLC for Delta.However this is only the starting current so for a given load the reduced starting current of star saves on cable installation costs but compromises the long term operational cost of the plant in that the motor current of Delta is far lower than the same motor connected in Star.The selection of motor starter type is dependant upon many influences including the type of operational parameters:Common Standard Motor Starters For 3 phase cage types are:DOL = Direct On LineStar/Delta = Main Star & DeltaSoft StartInverterPole Changing MotorsIt should be noted that a good rule of thumb for Variable Speed Motors supplied from an inverter its supply frequencySo: 50Hz +/- 25% = (37.5 - 62.5Hz) ((60Hz +/- 25% = (45 - 75Hz)) if the motor is expected to operate outside this range then independent forced cooling units mounted to the motors is recommended. This is due to the motor cooling necessary because of the increased thermal load of running the motor outside its designed operation window.The use of a pole changing motors together with an inverter can be significant torque boost at starting load in that the motor say for example was an 8/4 pole motor then the motor can start in 8 pole 750 rpm double torque then switch over to a 4 pole motor at normal torque at 1500 rpm, then add on the torque boost from the inverter and the torque can easily be doubled again.
Why did you bother writing this?
@@Impedancenetwork because he is smarter then us and this knowledge is easy for him to write
Thank you for this brief overview. 2 questions: A) how does my house get 120v/ 240v? B) What is a wild leg? (orange)
Your house only gets one phase, stepped down by a somewhat special transformer near you. This video is not relevant to your question about voltages. You get your two voltages from your single phase, local, center grounded transformer. From that center tap to each of the other two leads, you will get your 120VAC, from the ends of the secondary, its 240VAC. Its all about that center tap on the secondary of your local transformer. In the US, your wiring will be white for that center tap. This is neutral. Whoever sets up your breaker box will pick a side and it will be 120VAC or hot and it will be a black wire. The other side is usually wired red and it is reserved to use against the black to provide power to water heaters, stoves and other 240VAC services.
@@mscottmiracle1396 You would also use the red wire to feed 120v load that keeps the panel and transformer balanced. Both black and red wires feed 240v loads.
A "Wild Lag" would be the term for that unique 277 v different voltage winding on the rare type of 3 phase 240 Delta secondary X-former designed specifically for boost assisting the start rev of a industrial large motor(s) under weighted load like with commercial sludge pumps or the sawmill's saw blade drive motor. These are rare unless in an industry and prone to human factors when failing to recognize this unique X-former output. You are correct to lable that Wild Lag the color Orange as only that reveals to the eye to stay away when load balancing and always connect the ABC order perfect the first time with any Wild Lag motor type or you will smoke it baby and no one to blame for your bad guess work.
I'm bit nervous for new job on monday installing 3 phase 480 volt transformer , thanks for your help.
So how did it go???🤔
Awesome. Will appreciate a full class on three phase systems. Transformers and the Automatic transfer switch
Thanks prof, explained a lot well, wishing you well
On the ungrounded Delta, we add a neutral grounding Zigzag transformer and a resistor to create the grounding point. Works well
Isn’t that zigzag transformer wired in a wye configuration to get the neutral?
Good explanation! If I have two transformers (1&2) connected to each other; should the secondary connection of the main transformer (1) be the same configuration of the primary of the second transformer (2) ? Eg. should the connection be delta-delta ?
Good explanations,, very good 👍 PROUD TO BE ELECTRICIANS
I truly appreciate this Amazing breakdown!!!
I don’t know that I have ever seen a delta at 120 volts. All I’ve seen was either 240 or 480. The 240 with one transformer center tapped for 120 is quite common for commercial, so also is straight 480 for industrial, with 120 coming off a separate 480 to 240/120 transformer.
120/240 delta with a 208 high leg is a common older service used in my area..
This grid service type does exist as a 240 Delta (Not WYE), but with a center point tap (bonded to ground as our neutral buss between phase A and phase C often termed as a "Stinger". So then you get 240v between A&B, B&C, C&A, But then also can power standard receptacles that use a 120/240 Dual or "Split single" phase between A&C. For this one though, you must have a conjoined subpanel fed from the 3Ph MDP so that it can bond the center tapped Neutral to service ground point in that first MDP enclosure as close as possible to the secondary of the service X-Former. An electrician may be able to give a more current code explanation then me as I only have DC solar knowledge from my many installs with SMA inverter types that support the 240/120 Delta configurations but never came across one in USA service types. I'm eager to work with this in a hybrid router system since it would be superior if average use models are load balanced properly with our intermittent grids "Rolling Blackouts" reality coming to your theaters soon predictably.
yo that root 3 formula bro has solved so many problems with this shit
American Military generators use the Wye and Delta configurations, however, we use them in parallel and series connections using six independent coils. In a parallel Wye, we can get 120 single phase and 208 three phase, only. Our 5 and 10KW generators use both Wye and Delta configurations; parallel delta 120VAC single phase Only, series Delta 120/240VAC single phase, and parallel Wye for 120/208VAC. We can set up our 15KW through 200KW generators with either parallel and series Wye connections. The reason is for NATO power. On our parallel Wye we get the 120/208VAC and in series Wye we 240/416VAC. We also can set our generators to 50 or 60HZ. All the American Military generators have to be NATO compliant. I tell my students that when figuring the Wye three phase to take the line to neutral voltage and multiply by 1.732 for the three phase voltage (207.84). It's easier than going through the Trig computations.
Thank you for posting, this stuff interests me.
Hey. Really good info here - very useful. As far as learning more about this, is there a text you can recommend on Wye and Delta 3 phase configurations? Thank You.
Thank you so much for posting this and the other videos too.
In Russian they call the wye a "star" and the delta a "triangle". The instructor at the trade school was not anywhere near as lucid as you, and he was hung over half the time. I wish I studied with you as the instructor.
In Soviet Russia we don't say car - It's mobile home.
Well RUclips wasn’t made in Russia, this is America
Time for America, my friend. Some in Russian here also: www.chick.com
Great video. Why would you configure a motor in wye versus a delta? Most motors give you an option on how to connect it? Thanks.
Sure you can make more videos, you explain clearly.thank you thank you have an awesome days
Delta for slowly ramping up on specific needs of production or big equipment
very informative video
Good overview of this. Now to expand on this just a bit....I'm looking at installing a 3 phase solar inverter. It can be configured for either Y or Delta. In this case I'm thinking I would want to go with a Y configuration, however in some respect a Delta might be better. The only draw back I see at this point would be the lack of ground in the Delta circuit. What would be your thoughts on this?
Ground and Neutral are not the same thing. Delta configurations do not have a neutral, but they can still have a ground. None of the conductors are _grounded_ in a Delta configuration. In the Star/Wye configuration, the neutral carries the imbalance of the loads of the three phases, and it is usually directly grounded. Delta configurations must utilize an indirect kind of ground. I'm no expert, but the Wye configuration always sounds easier to me to implement.
+Kurt Langeberg - I tend to agree with Jovetj. The wye configuration is probably the better way to go, especially if this inverter is going to supply AC to an occupied building, off the grid. But the choice really depends on the total application. Is the system off the grid (with batteries) or is it grid-tied? If it is grid-tied then it must be compatible with the configuration that your power company is providing you with. If it's a standalone system that is charging batteries then the choice comes down to system voltage and capacity. High voltage/lower current systems would favor the wye system, lower voltage/higher current systems would favor the delta system. It can be quite the panoply of possibilities with these things. The key is knowing everything you can about the installation.
Depends... are you going to be charging other batteries or using appliances? or what?
thanks, needed this refresher 😁
Single phase systems provide 120/240VAC 120 phase to neutral and 240 phase to phase. The 120 degree separation on a three phase system as opposed to 180 degree separation on a single phase system is only there for smoother operation of three phase motors and such.
It's also there because it makes power generation, transmission, and distribution a lot more economical for the same amount of power.
@@carultch Yes, you are correct. Three is more symmetrical than two, even in terms of geometry. In other words three is more perfect than two.
Thank you so much sir you're teaching very well
I may have missed it but what about how delta can run with faults and is used in the nuclear industry and some Electric arc furnaces. Also the delta-wye/wye-delta transformation would of been good. Also some per phase/3 phase analysis would be nice
+Shredxcam22 - I can't answer all your questions but as far as a delta system running with faults, there is the case of the "open delta." This is when one of the phases is taken out of circuit for any number of reasons: maintenance, replacement of a bad component, etc. It is possible to do this in a delta system because the two remaining phases will actually recreate the missing phase and allow continued power flow to the loads that were handled by that phase. Of course allowances must be made to avoid overloading those two phases since they are now doing the work of three phases. Obviously this is a big advantage for power systems and "the grid" in general.
There are times when delta is not grounded, so if a phase goes to ground there is no current flow to activate protection. There is no current flow because of no relationship between transformer and ground. It would take two faults to ground on two different phases to create a current through ground and activate protection device. This is done on purpose so you don’t shut down that circuit for one fault. This advantage is needed for production oriented business.
thank you very much for your amazing videos!
would be great if you do a video on earthing systems!
What is the the coils connected in the center?
In Y configuration, How the Line current and Phase current are same? (They are not in series)
+Ajay G - Actually the phases and lines *are* in series in a wye system, so most certainly the currents would be the same between the two. The exception is the neutral wire, which has the three phases paralleled to it. So the current in that wire is the vector sum of the three phases. And if the three loads are equal (balanced), no current will flow through that wire. In those cases, such as three phase motors, the neutral can be eliminated.
Amazing video. Keep up the good work!
Could you please elaborate the sequence current and voltages developed below described scenarios. A 500KVA distribution transformer with 6% Z, 11/0.44 kV, Dyn11 connections lost one HV conductor. That conductor is on floating from source side and transformer side is touching with ground having less than 3 ohm ground resistance. So how much current will be developed in healthy phases and what will be the value of zero and negative sequence current
Very good stuff, but pse start with explaining DC: direct current and why we need (needed) AC at all.
There are a lot of videos on that already. No offense, but if you dont know the difference, then you really jumped ahead when you watched a transformer video. He expects you to know that already.
AC for power distribution and the workhorse of all industry, the simple and robust three phase induction motor.
I’m trying to start learning the electrical field as I have been working in the manufacturing field as a mechanic and have been exposed to electrical systems but haven’t been learning much over the past few years as our company doesn’t want to help us advance , now I want to expand my ability and branch out , that being said how would you suggest I start learning about industrial electronics.
thank for your explanation. I understand it clearly
Excellent information!👍👍👍👍
Helpful for me, thanks dude
at 1:28, I think you mean to say 240V when adding 120V + 120V in comparing to a center tap single phase system
I’m totally confused. I have an old crescent disc sander. It has a three-quarter horse three phase motor. There are four wires coming out of the motor. Two of the wires go down to the motor starter and connect to T1 and T3. The other two wires up at the motor are connected together. So it appears that the motor is only running on Two legs. T1 and T3. How is that possible? Anybody’s help would be greatly appreciated. Thank you
Yes...get into the math, Thanks!!!
Can you do a segment on buck boost transformer calculations. 1 phase 208 to 1 phase 240...
If you taking suggestions, the guy said industrial motor but VFD's are common but what about cycloconverters?
Shredxcam22 I'm gonna have to put you on payroll. Thanks for the awesome input. Seriously
The Electric Academy I went through a weird transition and have had to learn a lot. Avionics to working in a steel mill. I had to learn a ton but something are not often talked about. I plan on doing some videos eventually. I am finishing my BS electronics engineering technology which many people don't get the difference between EE and eet even tho both are ABET accredited.
@@Shredxcam22 So how did that go?
@@keyworksales6241 loving It. Working towards someday being a process/control engineering.
You do a nice job on doing the videos. Do one on safety.
Delta systems are used in high voltage transmission where the goal is to transfer bulk power
Is it possible to obtain 3phase power from a 1phase source? Ie if i need to power a 3phase CNC equipment in a residential/house that only has 1phase.
You are going to need a rotary phase converter, look up americanrotary.com, or you can build one yourself. Or you can go with a VFD, just make sure that you get one that requires 240V AC single phase on the input.
You said that the wye legs are 120 degrees apart, how many degrees apart are the delta legs? Also why was there only two legs with the delta?
There are 3 legs on the delta. Look again.
am I correct that for an alternator, the W phase is preferred, for the motor the delta - in case we are talking about a system in which the alternator feeds the motor (through a battery bank)?
Great video Friend! Thanks for explaining the Wye and Delta Configurations !
Well done . Well spoken .
-Subscribed
Nice, thank you for posting this.
Great explanation!
Can we ask questions?
In a 9 lead motor at high voltage the wye and delta are connected in the same configuration. How can I determine whether it is wye connection or delta then?
a nine lead motor is wye, period.
7,8,9 are terminated internally in a wye.
Could you proof how come square root 3 ? Thanks
can you do one more in depth about the differences of like corner grounded deltas and all the other ones. I'm an apprentice with the iec and went haven't gone over it to much in detail. probably my fault for not asking the right questions
How do troubleshoot ground faults
Solid slight skim. Subscriber now
Hey are you guy still going these videos?
Good job, thank you.
Thank you for sharing
Great video! Thank you you explain on how we obtain 120 V 208 V and 480 V but you didn’t clarify on 277. Can you please make a video on that? Thank you
480V is the phase-to-phase voltage of a 277V phase-to-neutral three phase system. The problem is inconsistent naming. We call it "120V three phase" and "480V three phase" but the first is named after the phase-to-neutral voltage and all other higher voltage systems are named after the phase-to-phase voltage. This is probably because the 120V systems are typically wired in Y configuration and higher voltages are typically in Delta configuration. In a Delta configuration, you would rarely use the phase-to-neutral voltage. But in a Y configuration the line voltage is frequently used. So the inconsistent naming convention makes sense with this logic.
It's a 480/277 Y system
Great video, questions, can you tell why in a transformer the primary is label "h" and the secondary is label "x"?
Great question dude
H=high side & X= excitation current
The “H” is the high voltage of the transformer. The “X” is the low voltage of the transformer. “Primary “ is the the side that magnetized the transformer. Secondary is the side the load is connected to. Typically primary is feed in the “H” side and the load is feed by the “X” side. In this configuration the transformer is in step down configuration. When you feed the transformer in the “X” side then that becomes the primary side and the”H” side feeds the load becomes the secondary side. In this configuration the transformer is in a step up configuration.
is it necessary to wire a 9 led 230/460 motor in delta to run my VFD
one point on a delta secondary in a transformer if the load is imbalanced there are circulating currents. on a wye system no circulation currents
Just ask Mike Holt. He knows ALL
On a delta connected system since there is no reference to ground what is the downside to having a wire shorted to ground. You won't notice it I assume but I assume that this will ultimately cause a problem. What would be the issue?
On these ungrounded Delta Systems there is a ground fault detection unit. The first ground fault is "free" and personnel is alerted by detection unit. It gives personnel time to find the fault without the whole system coming down. Another fault to ground on a different phase would create a phase to phase fault and that would trip main feeder breaker. These systems are used in process plants with majority motor loads.
@@ikerivers1795 so sounds like with delta if there is one fault it really doesn't matter. Only issue I can think of is that before with no fault if someone gets across a phase and ground there is no shock hazard, but once a fault occurs there would be a shock hazard if they the touched the other phase and were also grounded. Seems like a delta system is inherently safer unless there is some other aspect I am missing.
@@diyertime kind of...."shock" is the result of difference of "potential". Difference in voltage magnitudes regardless if your "grounded" or not. If you are grounded though that is an easy reference to near zero potential so whatever you touch is maximum potential difference.
@@diyertime This is a 3 wire Delta System I was describing. There are also 4 wire Delta Systems, where a grounded conductor i.e., neutral is derived from midpoint of a phase.
,
@@ikerivers1795 this gets to the heart of my question, what would be the advantage of adding this ground? Just so a fault is easily/quickly determined? Just as an fyi, I am a registered prof EE albeit most experience with computer engineering and rf electronics. I also did a stint for an electric utility. So if you need to be more technical its ok.
Line to line on the Delta would be 240V, not 120V. I think you misspoke, unless I am missing something.
would you please explain in depth synchronous machines and synchronous motors ..thx
Very useful !!! Thanks.
Well done !
Thank you very much teacher🌹
How about line to neutral
Great video thx.
He should review his videos and get the errors out before posting them. A tutorial should not contain elementary errors because they just confuse people who are trying to learn something.
cant see some of the text because of the huge intrusive watermark
Yeah I’m sorry about that. I don’t do that in my videos anymore. My bad 🤦♂️
Hey!
I just found your channel just now.
At this time in my life, i suddenly have electricity on the brain.
And this is like intellectual Kraft caramels to me; cant get enough.
Here's one for you,
I work on 115v ac machinery that has REVERSIBLE ac motors.
I would like to construct something whereby i could bench test them, as in, hook them up to power and run them outside the devices they are from so as to evaluate their condition overall.
Do you have a video on that sort of thing?
or could i trouble you for any links to such that you might be aware of?
Awesome thank you!
nice work thanks
Do a difference on 480v and 240v please
How can all three phases come together after the load being 120 degrees out of phase and nothing blow up. But if you cross phases before a load its a disaster?
+Caleb LeMay - If you are referring to how the three phases in a delta system can form a closed loop without blowing up, the answer lies in the fact that the VECTOR sum of the three voltages is always zero. So no current actually flows *around* the closed loop. You can actually see this by opening one corner of the delta and read zero volts or very close to it between the two leads. Put another way, it can be shown that the vector sum of the voltage of any two phases is always equal to the voltage of the third phase--again proving that no current will flow around the closed delta. This is one of the few cases where out of phase voltage sources can be directly cross-connected without blowing up. Chalk it up to the craziness of the math.
On a delta you have line leads on both sides of the motor so voltage is always present. I guess I don’t understand the vector sum.
Does the inductive load not have anything to do with it?
+Caleb LeMay - You need to find a good book on AC electricity. To start with, the type of load makes no difference in this point -- inductive, capacitive or resistive. The type of load will have a direct relationship on the phase angle between the voltage and current in the three lines going to the load but we are not talking about that here. As for vectors, think about the numbers that you see every day: the amounts you add and subtract in your checkbook, the prices of the groceries on your cash register receipt, all the different charges and credits you see on a utility bill, etc. All of these examples, in fact most numbers you work with in everyday life are examples of *scalar* quantities, numbers that solely represent an amount. Voltage, current and resistance in DC circuits are good examples of scalar quantities in electricity. Working with AC thrown in one more thing: *direction*. This makes up a vector. It denotes both magnitude (a scalar quantity) and direction (phase angle). Like other numbers, vectors can be written out like any other number -- with special notation so that you know it's a vector -- or graphically. This last method is usually the easier one to understand. For our purposes, perhaps this analogy will help you grasp the principle of the delta.
Imagine two 1.5 volt dry cells hooked together in series, but connected say, negative to negative instead of the usual negative to positive. Now, run a lead from the shared negative to two light bulbs connected together (not in series). Now, connect a lead from the positive terminal of each dry cell to the free terminal of each lightbulb. What do we get? Both lightbulbs illuminated. What we have are two independent circuits consisting of a dry cell (voltage source) and a lightbulb (load). With this configuration you can disconnect each lightbulb but the other one will stay illuminated despite appearing to be in series. Now, measure the voltages around the circuit. What do we have? 1.5 volts across each bulb, so we know we have two power sources driving their individual loads. But what do we get if we read the voltage from one positive terminal to the other? Answer: zero volts or very close to it. In other words, the voltage of one dry cell has cancelled out the voltage of the other without affecting the operation of the circuit or causing damage to either dry cell. This, in a more complicated way is what is happening with the closed delta loop. Some suggested things to look up: polar and rectangular vectors, the trigonometric functions (sine, cosine and tangent), and if you're really brave, the trig formulas for the sum of two angles (example: sine of angle A + angle B). Mastering this formula and plugging in the right numbers is the key to proving mathematically that no current will flow around a closed delta. Hope all this points you in the right direction (pun intended. LOL!)
Caleb, I assume you are looking at the centre of the Y configuration. Think of it as if you had three single phase motors each plugged into a separate plug with a unique hot phase of supply. Let's call them your blender, coffee grinder, and food processor. Each kitchen appliance has a two-wire connection of a hot phase supply and neutral return. Why is the return neutral? Reducing to utter basics, because the voltage has been "used up" (as power output of the motor) across the inductive coil of its motor. So the neutral has zero voltage and can be connected to ground.
So if you were to strip bare the neutral wires on your blender and grinder, and touch the neutrals together, there would be no problem, because there is no net voltage between them. The same applies inside a three-phase motor. The voltage has been "used up" across each coil. Since the voltages are 120 degrees out of phase with each other, the voltage is "used up" at slightly different times each cycle but each phase has a neutral (zero volt) side for the same reason a single phase motor does. To save wiring, the motor just ties those neutrals together into a singe wire.
How do you expect ppl to watch when your face is covering part of the information?
Perfect skimming of a potentially extensive topic.
Is that a 240v
What if earth fault come in one of the phase ?
Knowlegefull video
excellent.
Is it ok to use 127/240v from my gen with the ¥ configuration?
Finding ground faults in a floating ground system is tough lol
Didn't you tend bar in Deadpool?
9079 Travon Drive
Thank you! For this video.
How do you know a Delta from Hawaii
3780 Hamill Common
For somebody who's less advanced is the Delta configuration less complicated than the wire configuration
Allie Prairie
The grounded delta can be very dangerous if you don't know the system.
Your wiggy will show no voltage from ground to that leg and you'd assume
that there's a problem.