This producers of this video can describe the various transformers used in electric distribution systems, but don’t seem to be aware of the technology called STEREO!!
Worst thing about only having one high voltage line feeding transformers is that they are using the neutral ( ya now called grounded conductor in the NEC ) ,copper water service, meta gas pipe and even cast iron soil pipe to back feed the transformer. I have done hundreds of 100 & 200 amp services and even when I used a bigger copper wire from copper water line could still measure from 0.25 to 0.7 amps on gas pipe.Lazy cheap monopoly ultility companies should be made to use two high voltage wires to feed every single phase transformer when the second high voltage wires is on the same pole or close by.
Most utilities are using spoke grounds on every pole. This is tied into our system neutral that travels the entire distribution system. You may find grounds tied to customer water lines and such in the old infrastructure. However, that hasn’t been allowed for decades. The Customer is to install a driven ground outside their house for the house service. It is unfortunate that these conditions still exist. Until the customer upgrades their service nothing will change.
Most utilities are using grounds on every pole. Require if any piece of equipment is installed. This is tied into our system neutral that travels the entire distribution system. You may find grounds tied to customer water lines and such in the old infrastructure. However, that hasn’t been allowed for decades. The Customer is to install a driven ground outside their house for the house service. It is unfortunate that these conditions still exist. Until the customer upgrades their service nothing will change.
@@sissue62In my large city never saw the ultility run a ground pole to pole. The NEC mandates that you MUST bond anything that can become energized. You must run a copper wire within 5' of where copper water service enters a building. Some inspectors think you should bond the metal duct work in buildings especially if they have the flexible noise reduction joint that's non metallic. At an IAEI continuing education class an inspector brought up a great point. If a house has a stainless steel sink that is connected to a PVC drain & PEX tubing then a ground wire should be attached to any metal sink. Always thought that lady monopoly electric utility companies by not having to follow the NEC get away with murder. They refused to replace 75 year old fraying rubber covered #6 wire ( 60 amps for us ) while upgrading a hundred foot long 3 story building to a 100 & 200 amp services for a total of Amps. They said that being it was an underground service the ground cooled their wires. Pure Bullshit. Too lazy to jack hammer a side walk and replace worn out wires. Same thing with overhead services. I installed a 800 amp service and lazy ultility company connected it to a transformer that already was overloaded with a 200 & 600 amp service. Pole transformer burnt out twice in first year and jack asses continued to replace with same undersized transformer.
@@sissue62 my question for you is this: my electric utility used to have grounding equipment on every poll, but due to crack heads almost all of it has been cut off before it connects to the grounding post. How is the primary side grounded then to allow for continuity. After watching this video I'm guessing that the primary and the center neutral on the secondary are bonded and as such the primary is grounding through my main panel where the neutral is bonded to the earth. Is this correct? If so that's kind of scary and explains why I get small sparks if I disconnect earth from the water main (my house was last wired in 1953 so likely up to code then, but not now). I kinda wanna reconnect the earth on the pole now and see if the arcing stops. Hopefully you see this and reply. I'm genuinely curious.
@@danielgladstone1789 Yes. In the two-bushing version, the primary winding can be completely isolated from ground potential; this type of transformer is more versatile for installation in 3-phase configurations. When only one bushing is present, the other end of the primary winding is connected to the can case, which is then grounded, and connected to the neutral or shield or equivalent. The ground itself does not complete the circuit; just the one side of the circuit is kept at ground potential.
Stephen Shoihet Confusion. The center bushing is grounded in the video, but every pole mounted transformer that I see also goes to the property, where it is known as neutral. thank you.
How can these even work when it seems the components are so far apart, not magnetic coupli g, is it coupled di-electricaly through the oil? That seems weird. Is this cause they dont want the 7200 times current VA value stepped down by a 7200 to 120 positive ratio. That would be too much mains current to safely by shuttled to a home?
They are not as far apart in real life as they are depicted in the video. The secret is the iron core. All* electric conductors generate a magnetic field around them when electricity is flowing. (The opposite is true too: magnetic fields generate current in wires, which is how a generator works.) When the conductor is coiled together, that magnetic field is amplified. When the coils are put around a magnetic core, the field is greatly amplified. Static (unchanging) magnetic fields are not very useful for transformers. However, alternating current changes + and - polarity 60 times a second (in the U.S.). This causes the magnetic field to be constantly fluctuating. It's created and destroyed 60 times a second. The collapse of the concentrated magnetic field surrounding the iron core is what has the effect on the secondary coil in the transformer. All of the power the primary coil sucked up to create that magnetic field is discharged into the secondary coil. This is also why these coils are not "dead shorts"-power _is_ being utilized.
How does the power company complete the circuit? The top wire is the "P"ower wire and the next one down is the "N"eutral wire. But the nuetral is never hot, how?
It's a piss poor video and the words he throws around are just wrong, the other primary winding wire goes to a neutral wire, not ground although it is still "grounded" through the neutral so the chassis isn't live
I’ve worked several systems where you’d have a 3 phase 3 wire service that is “triplex”, I don’t know everyone’s lingo but like actual residential service wire.
My local power company has, for many years, designed pole line where the neutral/shield is on top, and the three phases were pinned on crossarms below. Don't assume "top=hot". The neutral is not "hot" because it is connected to the earth. This connection allows them to share the same voltage potential. In theory, standing on the ground and touching any grounded conductor is safe. Not all power lines have a grounded conductor. In that case, all of the wires are "hot."
@@Shane23Armada The second wire is not "The ground"... the second wire is just not discussed, but it's there. It just _happens_ to also be connected to the Earth. (e.g. grounded)
I'm not sure what you mean by "pop". If you are referring to a tripping of a circuit breaker, those types of utility transformers do not contain a circuit breaker. They will often be fused, but thats not relevant here. Because of CEMF (the wiring is going through an induction circuit) one side of the primary can be attached to a ground- it doesn't create a short. Some the ways they used to explain wiring concepts in this video is not universally true for all transformers- which can be confusing. Since a grounding conductor does not carry current during normal operation, I consider that second primary wire a "neutral", which is bonded to a ground. Same goes for the uninsulated wire in overhead triplex you see running down to a homes service (which is center tapped off the secondary and bonded to the outside frame of the transformer) thats not a "ground conductor" per se. Although it is connected to a home supplemental ground rod (or ufer ground, or ground loop, etc) during normal operation it is carrying the unbalanced current back to its source, the transformer.
@@howeelectric you mean on the primary side, the inductor makes a high impedance so that, even though after going to the inductor the wire goes to ground, the loss of power is small? Is this it?
This means that the primary circuit is always using maximum current even if the secondary circuit current load is low or even zero. This is very wastefull of energy is'nt it ?
The current on the primary is depending on the secondary current. If there is no load on the transformer, there is almost no currrent on the primary. Why do you think there would be always the maximum current?
@@deineroehre - Because the resistance of the primary winding doesn't change, the current should remain the same. I don't see any variable resistance in the primary winding.
@@cybair9341 You seem to have a huge misundertanding regarding transformers. It is an Inductor and no resistor, the resistance is not important (the resistance is only dissipating heat and is no use in the transformer), that is why inductors are measured in kVA and not kW. The fundamental use of an transformer is to interchange Voltage for Current between primary and secondary. 50kVA/7,2kV=6,9A on the primary side, 50kVA/230V=217A on the secondary side. If the load is less, eg 720Watts, then the current is 3,13Amps on the secondary and - with the interchange voltage for current on the transformer - the primary side has to deliver 720W/7200V=0,1A. If the current on the primary would be still 6,9A it would blow up the transformer rather quickly because ist would have to get rid of ~49kW in form of heat. That is absolutely not what these trashcantype transformers are designed for.
@@deineroehre - Thanks for the explanation. I looked up how inductors work and now I understand that the magnetic effect created in the core has a polarity which opposes the current that created it in the primary winding.
The typical 7,200 volt single phase line also connects to more than one single phase step down transformer. Being wired in parallel the current drawn is divided among the various transformers. Cybair
That’s a separate topic, but it isn’t complicated. The secondary is just a single phase at 220 to 240V. The secondary is tapped in the center, so it can be considered to be two 110 to 120V secondaries. They are in opposite phase because the hot lines are connected to opposite ends of the 240V secondary.
It's not explained very well in the video. The grounds talked about in the video are groundING conductors. They do not complete the circuit; they simply connect one side of the circuit to the same voltage potential of the Earth. You will notice that every power line has at least two wires. One of these is the "hot" and the other is usually a grounded neutral. The incoming neutral, transformer can, and outgoing neutral are all connected to ground to ensure they are the same voltage potential as the Earth. The whole idea of grounding is to control accidental voltage. If neither wire in the power lines were grounded, both would be dangerous to touch from the ground. Connecting one of them to the earth causes them to share the same voltage potential, making that wire (relatively) safe to touch. The same idea goes on in your home. The metal shell of your toaster should be connected to the ground wire of your home. This ensures that, should that shell become live from a lose wire or something, the live current will instantly find a quick path back to the source which will cause a quick overload and trip the circuit protection device. (The neutral and the ground are connected at the main panel, so the circuit gets completed that way.)
@@jovetj thank you for the reply. I get the grounding scheme to put the "neutral" leg at zero or earth potential to reduce shock hazard. What I don't understand is that there different numbers of wires to and from different transformers. Some transformers only have one wire going to them. Just never have been able to fully understand the circuit loop that is made from generating or distribution station to transformer(supply side). Sometimes I see 4 wires on poles, sometimes 3,2, and occasionally a single wire to a one home transformer.
@@stevewinwood3674 There are always two wires minimum that serve a transformer. Sometimes some triplex headed back in the direction of the source does double-duty of being the second conductor. The bare wire is the secondary neutral from the transformer and also the neutral from the substation. Remember that U.S. distribution current is alternating current, which changes +/- polarity 60 times per second. This polarity change is not instantaneous, though. If you graph it, it looks like a sine wave. Power plants generate electricity in three phases. Each of the three phases peaks out at different times and in a regular pattern. This allows power to be transmitted more efficiently, and also allows things like motors to be more powerful and efficient. The utility only runs power lines with all three phases when they're all needed. In residential neighborhoods, or rural areas without farms, its' common to see just one of the "hot" phases. If you see just one transformer on a pole with four wires strung to or through it, you can note that the transformer's high voltage tap only connects to one of the phases. If there are 2 or 3 transformers on a pole, that is likely for a three-phase customer. Unfortunately, there are several different types of 3-phase service which is just not possible to explain here. There are several videos on YT that explain three-phase transmission and distribution, though. The key point to take away is much more power can be delivered with three wires (delta three phases) or four wires (wye three phase) than with just two wires alone. Most transmission in the US is done with delta three phase.
@@jovetj thank you again for the reply. If you look below in other comments you will see a line man talking about single wire distribution. It does occur.
My left ear enjoyed this video.
Right ear for me.
Same
What does that mean?
This producers of this video can describe the various transformers used in electric distribution systems, but don’t seem to be aware of the technology called STEREO!!
I was like “why is it so quiet?” Then I saw your comment and realized I only had one headphone in LMAO.
He's got a voice that just screams, "I speak the truth!"
I'm here because I was curios.....thanks for the free education.
Good explanation
Very good explanation
Tks a lot
Awesome transformer.
Nice presentation
I put my left earphone on my right ear at the second half so it won't get jealous.
What happens to your right ear?😮
and here i am checking if my new earphone is broken
Thanks, greetings from Mexico.
Worst thing about only having one high voltage line feeding transformers is that they are using the neutral ( ya now called grounded conductor in the NEC ) ,copper water service, meta gas pipe and even cast iron soil pipe to back feed the transformer. I have done hundreds of 100 & 200 amp services and even when I used a bigger copper wire from copper water line could still measure from 0.25 to 0.7 amps on gas pipe.Lazy cheap monopoly ultility companies should be made to use two high voltage wires to feed every single phase transformer when the second high voltage wires is on the same pole or close by.
Most utilities are using spoke grounds on every pole. This is tied into our system neutral that travels the entire distribution system. You may find grounds tied to customer water lines and such in the old infrastructure. However, that hasn’t been allowed for decades. The Customer is to install a driven ground outside their house for the house service. It is unfortunate that these conditions still exist.
Until the customer upgrades their service nothing will change.
Most utilities are using grounds on every pole. Require if any piece of equipment is installed. This is tied into our system neutral that travels the entire distribution system. You may find grounds tied to customer water lines and such in the old infrastructure. However, that hasn’t been allowed for decades. The Customer is to install a driven ground outside their house for the house service. It is unfortunate that these conditions still exist.
Until the customer upgrades their service nothing will change.
@@sissue62In my large city never saw the ultility run a ground pole to pole. The NEC mandates that you MUST bond anything that can become energized. You must run a copper wire within 5' of where copper water service enters a building. Some inspectors think you should bond the metal duct work in buildings especially if they have the flexible noise reduction joint that's non metallic. At an IAEI continuing education class an inspector brought up a great point. If a house has a stainless steel sink that is connected to a PVC drain & PEX tubing then a ground wire should be attached to any metal sink. Always thought that lady monopoly electric utility companies by not having to follow the NEC get away with murder. They refused to replace 75 year old fraying rubber covered #6 wire ( 60 amps for us ) while upgrading a hundred foot long 3 story building to a 100 & 200 amp services for a total of Amps. They said that being it was an underground service the ground cooled their wires. Pure Bullshit. Too lazy to jack hammer a side walk and replace worn out wires. Same thing with overhead services. I installed a 800 amp service and lazy ultility company connected it to a transformer that already was overloaded with a 200 & 600 amp service. Pole transformer burnt out twice in first year and jack asses continued to replace with same undersized transformer.
@@sissue62 my question for you is this: my electric utility used to have grounding equipment on every poll, but due to crack heads almost all of it has been cut off before it connects to the grounding post. How is the primary side grounded then to allow for continuity. After watching this video I'm guessing that the primary and the center neutral on the secondary are bonded and as such the primary is grounding through my main panel where the neutral is bonded to the earth. Is this correct? If so that's kind of scary and explains why I get small sparks if I disconnect earth from the water main (my house was last wired in 1953 so likely up to code then, but not now).
I kinda wanna reconnect the earth on the pole now and see if the arcing stops. Hopefully you see this and reply. I'm genuinely curious.
@@Carveaholic You definitely have a ground leak. You should reconnect that pole before you get an errant fire.
Great information. Many thanks
this is fantastic
Where did you find this video?! I want to see em all
Does this mean that two phases are coming out of the transformer with the lower voltage because it is center tapped?
Very Good but i drank 20 cups of Coffee to make it to the end
I wanna see the rest of the videos now
What’s the advantage or disadvantage of the single primary style?
Good information thanq sir...
He is really sinequanon in teaching
Oh yeah that's right a transformer has a secret in it. Ok please be careful.
No mention of Counter EMF, the reason one end of the coil being grounded isn’t a direct short.
Does the current in the primary use this ground to flow back to the substation?
@@danielgladstone1789 Yes. In the two-bushing version, the primary winding can be completely isolated from ground potential; this type of transformer is more versatile for installation in 3-phase configurations. When only one bushing is present, the other end of the primary winding is connected to the can case, which is then grounded, and connected to the neutral or shield or equivalent. The ground itself does not complete the circuit; just the one side of the circuit is kept at ground potential.
No mention of the neutral (from the center bushing of the secondary winding)
going to the customer property?
No, because the ground in the panel inside the house is tied to the neutral bus bar.
Stephen Shoihet Confusion. The center bushing is grounded in the video,
but every pole mounted transformer that I see also goes to the property,
where it is known as neutral. thank you.
If my neutral conductor, leaving the house, toward the transformer had voltage on it?
I would look for an " Open Neutral."
Very dangerous condition.
@@nix324 if neutral earthed is it brought down to relatively zero potential?
Right I think of it as a " return " @@nix324
How can these even work when it seems the components are so far apart, not magnetic coupli g, is it coupled di-electricaly through the oil? That seems weird. Is this cause they dont want the 7200 times current VA value stepped down by a 7200 to 120 positive ratio. That would be too much mains current to safely by shuttled to a home?
They are not as far apart in real life as they are depicted in the video. The secret is the iron core.
All* electric conductors generate a magnetic field around them when electricity is flowing. (The opposite is true too: magnetic fields generate current in wires, which is how a generator works.) When the conductor is coiled together, that magnetic field is amplified. When the coils are put around a magnetic core, the field is greatly amplified.
Static (unchanging) magnetic fields are not very useful for transformers. However, alternating current changes + and - polarity 60 times a second (in the U.S.). This causes the magnetic field to be constantly fluctuating. It's created and destroyed 60 times a second. The collapse of the concentrated magnetic field surrounding the iron core is what has the effect on the secondary coil in the transformer. All of the power the primary coil sucked up to create that magnetic field is discharged into the secondary coil. This is also why these coils are not "dead shorts"-power _is_ being utilized.
@@jovetj Canada too Buddy..... Not just theRe in the US... Ha
How does the power company complete the circuit? The top wire is the "P"ower wire and the next one down is the "N"eutral wire. But the nuetral is never hot, how?
It's a piss poor video and the words he throws around are just wrong, the other primary winding wire goes to a neutral wire, not ground although it is still "grounded" through the neutral so the chassis isn't live
I’ve worked several systems where you’d have a 3 phase 3 wire service that is “triplex”, I don’t know everyone’s lingo but like actual residential service wire.
The neutral bus bar in the house is tied to ground.
My local power company has, for many years, designed pole line where the neutral/shield is on top, and the three phases were pinned on crossarms below. Don't assume "top=hot".
The neutral is not "hot" because it is connected to the earth. This connection allows them to share the same voltage potential. In theory, standing on the ground and touching any grounded conductor is safe.
Not all power lines have a grounded conductor. In that case, all of the wires are "hot."
Hi can you explain why one wire on primary bushings?
@Sophia Ramirez thank u
@@Shane23Armada The second wire is not "The ground"... the second wire is just not discussed, but it's there. It just _happens_ to also be connected to the Earth. (e.g. grounded)
This. Makes me want to learn more. Old McDonald had a farm. E I e I o.
why is the primary going to ground? why does that not pop the transformer primary, but it does pop the secondary?
I'm not sure what you mean by "pop". If you are referring to a tripping of a circuit breaker, those types of utility transformers do not contain a circuit breaker. They will often be fused, but thats not relevant here. Because of CEMF (the wiring is going through an induction circuit) one side of the primary can be attached to a ground- it doesn't create a short. Some the ways they used to explain wiring concepts in this video is not universally true for all transformers- which can be confusing. Since a grounding conductor does not carry current during normal operation, I consider that second primary wire a "neutral", which is bonded to a ground. Same goes for the uninsulated wire in overhead triplex you see running down to a homes service (which is center tapped off the secondary and bonded to the outside frame of the transformer) thats not a "ground conductor" per se. Although it is connected to a home supplemental ground rod (or ufer ground, or ground loop, etc) during normal operation it is carrying the unbalanced current back to its source, the transformer.
@@howeelectric ok so being grounded doesnt create a short is what i was referring to.
@@howeelectric you mean on the primary side, the inductor makes a high impedance so that, even though after going to the inductor the wire goes to ground, the loss of power is small? Is this it?
@@gabrielphilips6980 No.
This means that the primary circuit is always using maximum current even if the secondary circuit current load is low or even zero. This is very wastefull of energy is'nt it ?
The current on the primary is depending on the secondary current. If there is no load on the transformer, there is almost no currrent on the primary. Why do you think there would be always the maximum current?
@@deineroehre - Because the resistance of the primary winding doesn't change, the current should remain the same. I don't see any variable resistance in the primary winding.
@@cybair9341 You seem to have a huge misundertanding regarding transformers.
It is an Inductor and no resistor, the resistance is not important (the resistance is only dissipating heat and is no use in the transformer), that is why inductors are measured in kVA and not kW.
The fundamental use of an transformer is to interchange Voltage for Current between primary and secondary.
50kVA/7,2kV=6,9A on the primary side, 50kVA/230V=217A on the secondary side.
If the load is less, eg 720Watts, then the current is 3,13Amps on the secondary and - with the interchange voltage for current on the transformer - the primary side has to deliver 720W/7200V=0,1A.
If the current on the primary would be still 6,9A it would blow up the transformer rather quickly because ist would have to get rid of ~49kW in form of heat. That is absolutely not what these trashcantype transformers are designed for.
@@deineroehre - Thanks for the explanation. I looked up how inductors work and now I understand that the magnetic effect created in the core has a polarity which opposes the current that created it in the primary winding.
The typical 7,200 volt single phase line also connects to more than one
single phase step down transformer. Being wired in parallel the current drawn
is divided among the various transformers. Cybair
This video doesn’t explain how we get 2 phases (110v + 110v) out of the secondary winding to produce 220vac in the house
That’s a separate topic, but it isn’t complicated. The secondary is just a single phase at 220 to 240V. The secondary is tapped in the center, so it can be considered to be two 110 to 120V secondaries. They are in opposite phase because the hot lines are connected to opposite ends of the 240V secondary.
@@GH-oi2jf would love to see a little hand drawing that can illustrate what you just said here. But thanks for explaining it anyway
How does the electricity make a complete circuit if one side goes to ground?
It's not explained very well in the video. The grounds talked about in the video are groundING conductors. They do not complete the circuit; they simply connect one side of the circuit to the same voltage potential of the Earth.
You will notice that every power line has at least two wires. One of these is the "hot" and the other is usually a grounded neutral. The incoming neutral, transformer can, and outgoing neutral are all connected to ground to ensure they are the same voltage potential as the Earth.
The whole idea of grounding is to control accidental voltage. If neither wire in the power lines were grounded, both would be dangerous to touch from the ground. Connecting one of them to the earth causes them to share the same voltage potential, making that wire (relatively) safe to touch.
The same idea goes on in your home. The metal shell of your toaster should be connected to the ground wire of your home. This ensures that, should that shell become live from a lose wire or something, the live current will instantly find a quick path back to the source which will cause a quick overload and trip the circuit protection device. (The neutral and the ground are connected at the main panel, so the circuit gets completed that way.)
@@jovetj thank you for the reply. I get the grounding scheme to put the "neutral" leg at zero or earth potential to reduce shock hazard.
What I don't understand is that there different numbers of wires to and from different transformers. Some transformers only have one wire going to them. Just never have been able to fully understand the circuit loop that is made from generating or distribution station to transformer(supply side). Sometimes I see 4 wires on poles, sometimes 3,2, and occasionally a single wire to a one home transformer.
@@stevewinwood3674 There are always two wires minimum that serve a transformer. Sometimes some triplex headed back in the direction of the source does double-duty of being the second conductor. The bare wire is the secondary neutral from the transformer and also the neutral from the substation.
Remember that U.S. distribution current is alternating current, which changes +/- polarity 60 times per second. This polarity change is not instantaneous, though. If you graph it, it looks like a sine wave. Power plants generate electricity in three phases. Each of the three phases peaks out at different times and in a regular pattern. This allows power to be transmitted more efficiently, and also allows things like motors to be more powerful and efficient. The utility only runs power lines with all three phases when they're all needed. In residential neighborhoods, or rural areas without farms, its' common to see just one of the "hot" phases.
If you see just one transformer on a pole with four wires strung to or through it, you can note that the transformer's high voltage tap only connects to one of the phases. If there are 2 or 3 transformers on a pole, that is likely for a three-phase customer. Unfortunately, there are several different types of 3-phase service which is just not possible to explain here. There are several videos on YT that explain three-phase transmission and distribution, though. The key point to take away is much more power can be delivered with three wires (delta three phases) or four wires (wye three phase) than with just two wires alone. Most transmission in the US is done with delta three phase.
@@jovetj thank you again for the reply.
If you look below in other comments you will see a line man talking about single wire distribution. It does occur.
@@stevewinwood3674 Perhaps. There is also one wire (DC) transmission. But that is rare.
Secondary winding has 3 wires going to each home NOT 2 !
Two hot and one neutral?
@@Vekoma1261 which equals 3
Learn a few method of how a tranformer work
Sir please tell me how we connect three single phase transformer in star star
A 4 wire Wye?