Thanks I'm here because our power got knocked out by Helene and we didn't have it for 11 days. I watched our linemen but I wanted to learn more. Appreciate all the linemen out there and my heartfelt thanks for all the sweat and blood and tears you put into it.
I got a job being an electrical designer and it’s so refreshing to see this hands on instead of just behind a screen on a program! Thank you so much this was so informative and helpful.
Thanks. I’ll clear up some of the stuff I missed in the next video. Like explaining what the lighter pot and power pot means. And the proper way to energize the bank.
An Excellent demonstration!!!!Very informative!!! awesome tutorial!!!The best Lectured you gave thank you so much for your content very Educational. Charlie G, Dela Cruz/Philippines,:-))).....
Very well done video. Couple things I would suggest is explaining to your students why you don't have a phase to phase or a phase to ground fault situation when the tub is energized, being that you have continuity between the H1 primary bushing and the grounded H2 bushing and your X1, X2 and X3 secondary bushings. It's a question I get often from apprentices. Also explain why, when you're taking the secondary neutral/tank connection off for your continuity test, why you're doing it, although it's not really necessary in this example, being it's a dual bushing transformer and the H2 isn't bonded to the tank giving you continuity between the primary bushings and the secondary bushings via the tank. If it was a single bushing transformer where the primary coil on the H2 side just went to the tank ground instead of the H2 bushing that would be necessary.
Yes sir. Thankyou for the suggestions. I appreciate it. A lot of times when doing these lessons I have to try and not feed everyone with a fire hose. I’m sure you can agree that when trying to plan a lesson you have to be pretty intentional with the “what” and “how” to get the point across. When your doing a “Video” lesson it’s even more so, since you don’t have the interaction with the students. Stay safe and keep teaching. If I can help in any way, let me know. 👍
Lol. The old Asbury loop. So all they’re talking about is tying your H2 connection (or the primary neutral connection to the secondary X2 bushing on primary grounded wye systems.) Some places do this. Everyone else doesn’t. If you look at the connection in the lesson, the primary neutral connection and the secondary X2 connection are tied to the same system neutral. So they’re already at the same potential. They’re a no need to make another connection from H2 to X2. This is a topic of debate among engineers and in my opinion I would say there is more of a advantage to not do it than to do it. 👍
@@mmavoidlol. Ya I hear ya. Pretty much everywhere you go. The utility thinks they invented linework and assume that everyone knows what all their little slang terms mean that only exist there. Keep learning. Stay safe. 👍
@@hilineacademy8482 thank you, stare safe as well! I have line school and a cdl a and I’ve signed the books worked a little bit, but works been slow up here and I’m on book 3 and don’t have a truck or trailer. Any tips on how I should go about trying to get experience despite all that?
@@mmavoid lol. Yes move. There’s a ton of work in Az. Lots of transmission work and not enough men to do it. Call 769 and see what they say. Let them know you have a cdl.
Good question. So it depends on what type of circuit your working on. If your working on a grounded neutral system, the primary and secondary share the same neutral and the neutral goes back to the substation transformer. If your working on an UNgrounded neutral system the primary has its own neutral that goes back to the substation transformer and the secondary neutral does not. It goes back to the distribution transformer. The secondary neutral will be grounded and it’s localized to the secondary circuits. On these systems we don’t tie the primary and secondary neutrals together. Stay safe 👍
Thanks for the info. That makes sense. Now what about the primary side of the substation transformer? Is there also a neutral line on the grid that goes back to the power plant or is neutral generated at the substation?
Utility companies are ridiculously cheap to save "Earthed wires". The primary Neutral and secondary Neutral shouldn't be tied together at all. It defeats the purpose of an isolation transformer. It should be only allowed to be tied together with " a designated Earthed Wire."
Are two people required when working on the low voltage side of a pad mounted transformer while reconnecting a service that has previously been disconnected and do you have to wear sleeves when working on the secondary voltage side?
To be honest. You’ll need to check with the rule book for the property that you’re working on. When it comes to safety rules you’ll find that the rules change quite a bit depending on the utility you’re working for. Stay safe. 👍
and the neutrals of the 7200/12470 volt and the 120/240 volt side are connected to each other? And the transformer is local grounded directly below i think
Yes sir. The simulator I built has a grounded wye primary circuit. In that circuit the primary and secondary neutrals are shared. But it’s not like that on an ungrounded wye. On that circuit the primary has its own neutral and the secondary has its own neutral. Then on a delta primary circuit the primary doesn’t have a neutral but the secondary does. So depending on what kind of circuit you’re working on can look quite different from each other both in construction and how you work on them.
Question please. The circuit neutral (the top wire on your markup)goes back to the substation? If ONLY one bushing on top of the can, how does the equipment ground go back to the substation? we under multipoint grounded neutral at EACH POLE that has a transformer. We are looking for a PARALLEL neutral system ( multipoint to earth and a separate conductor back to the substation.
So with a single bushing transformer, the ends of the transformer coil connect from the insulated bushing to the pot lug on the case of the transformer, which we connect to the grounded neutral. Current flow travels from the phase - to the insulated bushing - through the primary coil - and out the pot lug which we connect to the grounded neutral, and returns back to the sub station transformer.
They were 1/2 KVA transformers that blew up off of a cap bank. But I stripped the cores and rewound them to have a 120 primary coil and a 120/240 secondary output.
I don’t currently have the setup to do hands on underground lessons but I hope to in the future. If you have any questions don’t hesitate to ask. Stay safe. 👍
How do you decide which phase to use for the primary? Does the utility have to keep the loads on each phase in their distribution balanced i.e. if every pole transformer in the city were connected to the same phase would that cause a problem?
I like your teaching technique of using a common item - inches of the discription of the y connection instead of some over the top technical word or phrase. That in itself is more practical and I can understand that more clearly .
when you install the transformer at the customer's place, does the center tap gets connected to the Grid's neutral (the one that runs along 7200V lines). In other words, is there another wire that connects the center tap and the grid's neutral?
Good question. It depends on what kind of primary circuit is feeding transformer. If it’s an ungrounded wye primary circuit the primary neutral and the secondary neutral are separate. The secondary neutral is grounded since it’s feeding homes. The primary neutral is not grounded. It serves to return all of the unbalanced current on the primary circuit back to the sub. If it’s a grounded wye primary circuit usually the primary and secondary will share a neutral unless they are using it as a static. I know it’s all kind of confusing but I hope I answered your question. If not please let me know. Stay safe 👍
@@hilineacademy8482 Actually, you answered my question perfectly! thank you! However, in the case of grounded primary wye circuit where primary neutral and secondary neutral are connected, under NORMAL operation, should there be any current passing from one side to the other?
@@hilineacademy8482 May I ask that the secondary (@7:20) neutral is bonded with the primary neutral as well. This connection makes the isolation transformer become an autotransformer. The isolation transformer is NOT an isolation transformer anymore. In my opinion the Primary Neutral and Secondary Neutral should be grounded to earth independently and isolated from each other. Or if lightning hits the power transmission lines , all the surges will go to the secondary side as well and damage lots of appliances and electronics equipment. Please correct me if I'm wrong.
How is the H2 going to ground not energized or is it? Like, I guess the hot primary coming in is at the top of the supply coil and this H2 is at the bottom of the coil but yet it's not carrying voltage yet its continuous with the hot primary coming in? Like, how?
Excellent presentation I Have a silly question if the neutral wire is part of the same secondary hot winding why you don't get shocked by touching the neutral wire? i only know current returns to the source via the neutral wire thanks!
That’s a good question. When we get shocked, it’s because we become part of the circuit. Meaning we get in series between two points of the circuit that are at different potentials. If we only come on contact with one part of the circuit, no current would flow through us. We would have to come in contact with another part of the circuit that is at a different potential in order for current to flow through us. So really you can touch any part of a circuit as long as you don’t make a second point of contact with a different part of the circuit. This is how live line barehand work is done. Hope this answered your question. Let me know if you need a better explanation. Stay safe. 👍
so I'd assume your setup is most likely energized to 7200/12470. but how are you actually powering this setup on the high side? is there another transformer that takes 120/240 or whatever and bumps it up to high voltages? I am curious.
Great question. The primary is 120/208 3 phase 4 wire. I don’t have three phase at my house so I took 240 single phase and ran it through a phase converter to get 3 phase 240 3 wire. Then I wound a conversion bank that is 240 3 phase to 120/208 3 phase 4 wire. On the secondary side I have multiple taps so I can regulate voltage on the 120/208. Also on all the transformers I use I stripped the cores and bobbins and rewound them to either 120 primary or 208 primary input. And the secondary side I wind to whatever secondary voltage I need. It’s a ton of work. 😓
@@hilineacademy8482 ah, I see. when you do this, do you leave the oil inside the transformers in them? or did you drain it out because this is a demo setup that is probably never going to be on any load.
@ I drained them. It was super messy too. Some of the transformers were blown up and had black soot and burnt oil in them. It was a ton of work to clean them up and strip the old bobbins but yes since there’s no real load on them there was no need to cool them with oil.
We’ll to create three phase voltage out of single phase transformers, you would need to build a transformer bank out of multiple transformers. Go watch the lesson I did on vectoring. It will give the groundwork to understand where the voltages come from and how to build them. Stay safe👍
Question. Single phase step down transformer ONE Bushing on top. All the neutrals AT THIS POLE are connected to earth at this location. We understand this is multipoint grounded (each pole) neutral system). Where is the distribution neutral BACK TO THE SUBSTATION? thank you
Not sure about 3 cut outs on short arm. And a piece of equipment. We tend to put equipment on oneside cutouts of power job 3 transformers on the other. Capacitor banks, reclosers, step downsand underground risers... Alot happens when there's a fault and other factors that add to it... Making it a bigger fire ball... Line wrench works great... Paid by hour
Question please. 3 phase Wye Wye. Understand the primary is grounded. The question is the secondary coils are NOT in series (as usual)but wired in parallel. Explanation for this ? why needed?
So when your building a 120/208 bank, and your using 120/240 transformers. You only need 120 volts from each transformer. The 120/240 transformer has 2 - 120 volt coils in series from the factory, which can each output 1/2 of the total amperage that the transformer is rated for (Example: a 25 KVA transformer is good for about 104 secondary amps. That means that each 120 volt coil is good for 52 amps @ 120 volts, and good for 104 amps @ 240 volts if the transformer is in series) so if you leave the secondary coils in parallel and only use ONE 120 volt coil, you aren’t using the total KVA of the transformer. Your only using half. So to utilize the total KVA of the transformer you need to PARALLEL the secondary coils so you are using both of the 120 volt coils to feed the bank. That way you are using the total KVA of the transformer. If you don’t, the customer will not be getting the total amperage available to them and when their service is at 100% load, the voltage drop will be great, and they will burn up equipment. To learn how to parallel secondary coils watch the lesson that’s titled “ Alley Cat Bad Dog”. 👍
Can you please tell me how to calculate, the fuses in the primary for a transformer 600 volts, 3 phases, 75 KVA? Primary Delta and secondary Why. Thanks.
Enjoying your videos. Dumb question: why is this called a “single phase” hook up when there are actually two 120V outputs that are 180° apart ( i.e. 2 phases)?
Great question. So the term single phase came from back when we used to supply only a 120 two wire services. Phase to neutral. That’s one theory. Another one is that we are only working with one phase angle. Either way it’s just the lingo now lol. Stay safe 👍
Gud day. What if the source of my 220 volt is from 10 kva syncronous a.c. single phase alternator and my actual total load is 18kw. My question is, what type of transformer im going to use??? Please give me advise.
Firstly. If your load is 18kw, and your generator is only capable of supplying 10kva, which is 10kw. You won’t be able to support the load. Using a transformer to change voltage will not help the problem. Higher voltage can push more load, but only if the source generator is big enough. To calculate wattage, the equation is Watts = Volts multiplied by Amps. So if you generator will only support 10kw. You can step up and down the voltage and only change the amps. It sounds like you need a bigger generator. Please let me know if I answered your question. Be safe.👍
So there is two pieces of info that are required in order to figure this out. First you need to know the voltage the transformer is asking for and the second is to know what circuit voltage and type of circuit you are working on. From these two pieces of information we determine what hookup is required in order to feed the transformer with the correct voltage. I did a video lesson on this exact thing. It’s called “what you need to know”. If you have any more questions let me know. Stay safe 👍
Ya I hear ya. I dont have three phase at my house so I made a simulator which consists of a phase converter that outputs unbalanced 240 three phase and I wound a conversion bank that outputs 120/208. But since the 240 is unbalanced my 120/208 is a little off. I tapped out multiple voltages out but it’s still a little off. That’s what I was talking about.
Ok wait how are you actually feeding that pot? Great video brother. You should try to get your hands on a conventional single bushing pot. That’s what we use on Long Island. The case ground is actually your h2. We make three points of bonding on that connection. Guys seem to think it’s just a case ground but it’s actually the primary return. All around great video though
Thanks for the encouragement. I really appreciate it. I built a mobile simulator in my backyard. I only have 120/240 single phase at the house. So I bought a rotary phase converter which gave me 3 phase 240. Then I hand wound a conversion bank 240 delta to 120/208 wye which feeds my simulator with a three phase extension cord. And I have single bushing transformers at the house. I just haven’t wound the cores for them yet. And yes a lot of people think that the h2 bushing on those pots are just a case ground. It’s pretty scary. I’m hoping that these videos help to educate and demystify transformer hookups. Thanks for the encouragement and if you ever have any questions please don’t be afraid to reach out. Stay safe 👍
@@hilineacademy8482 yessir of course love learning theory. On the Csp pots I e seen guys run the pole ground straight through the h2 lug “case ground” and only make one connection to system neutral. No bueno. If that tap corrodes or comes lose there is primary potential on that tail. We actually make up a 6’ copper lead bend in the middle so it’s a continuous loop with 2 tails. One tail bonds to pole ground pole ground fire Tito system and other tail directly to system. So there is 3 points of bonding. One fails there is two still bonded.
Lol. I understand. The focus of this video was mainly to understand the process of determining the primary and secondary hookup. There will be more videos out soon on different hookups and applications. Thanks for the feedback. I hope they’re helping to answer some of the questions about transformer theory. Stay safe. Thanks.
That’s a csp pot bud. Try to get outside of your jurisdiction and you come to find what a conventional transformer is. Csp the case ground is your h2 so there is only one primary bushing on the top. On my system we basically use all Csp one bushing pots but the higher kva❤rated pots basically 75kva and up all have 2 bushing high sides. Some systems they have a grounded wye system but on their laterals they run 2 phase delta and all their pot need phase 2 phase voltage. We call them a delta pot h1 to one phase h2 to another given the full phase to phase voltage in this case 7200v
baobao question: with one primary bushing on top of the can, do we have a neutral conductor going BACK to the substation? thank you We understand that EACH transformer (along the single phase, 7200 volt line) is part of a MultiPoint grounded neutral system to the earth.
Those have the other end of the primary coil internally grounded to the can. They're for phase to ground connections only. The kind shown in this video can use a phase to phase primary connection.
Thanks I'm here because our power got knocked out by Helene and we didn't have it for 11 days. I watched our linemen but I wanted to learn more. Appreciate all the linemen out there and my heartfelt thanks for all the sweat and blood and tears you put into it.
I got a job being an electrical designer and it’s so refreshing to see this hands on instead of just behind a screen on a program! Thank you so much this was so informative and helpful.
No problem. Any time. Don’t hesitate to ask questions. If I can help in any way I will. 👍
Excellent and educational video. Nice work!
Thank you sir.
Clear, concise, and nicely demonstrated. Any novice should be able to utilize this information and learn . Great refresher for seasoned pro.
Yes sir.👍 thank you for the encouragement. I appreciate it!
Thanks for the clear explanations, mechanical details (well filmed) and Wye Delta Neutral white board pics. These videos are great!
Thanks. I’ll clear up some of the stuff I missed in the next video. Like explaining what the lighter pot and power pot means. And the proper way to energize the bank.
Did you make that simulator
@@giacomotallarida4946 yes I did. It was a ton of work but I learned a lot. Especially when it came to winding the conversion bank.
You have a gift to transfer complicated subject matter simply! 😆
Thank you. It’s a process. Believe me. 😂
It's an amazing explanation. Thank you very much.
👍 thank you. Stay safe.
An Excellent demonstration!!!!Very informative!!! awesome tutorial!!!The best Lectured you gave thank you so much for your content very Educational.
Charlie G, Dela Cruz/Philippines,:-))).....
Thanks Mr. Cruz. I appreciate it. Stay safe👍
Great job sir! I always passed by those and couldn’t make sense of it
This would have been an awesome tool when I went through my apprenticeship.
Yes sir. Thank you 👍
your explanations are golden... keep up the great work!
Thank you. I’m glad they’re helping. Stay safe 👍
Very well done video. Couple things I would suggest is explaining to your students why you don't have a phase to phase or a phase to ground fault situation when the tub is energized, being that you have continuity between the H1 primary bushing and the grounded H2 bushing and your X1, X2 and X3 secondary bushings. It's a question I get often from apprentices. Also explain why, when you're taking the secondary neutral/tank connection off for your continuity test, why you're doing it, although it's not really necessary in this example, being it's a dual bushing transformer and the H2 isn't bonded to the tank giving you continuity between the primary bushings and the secondary bushings via the tank. If it was a single bushing transformer where the primary coil on the H2 side just went to the tank ground instead of the H2 bushing that would be necessary.
Yes sir. Thankyou for the suggestions. I appreciate it. A lot of times when doing these lessons I have to try and not feed everyone with a fire hose. I’m sure you can agree that when trying to plan a lesson you have to be pretty intentional with the “what” and “how” to get the point across. When your doing a “Video” lesson it’s even more so, since you don’t have the interaction with the students. Stay safe and keep teaching. If I can help in any way, let me know. 👍
Very informative
Thank you 👍
best tuitorial ever
Thanks buddy. 👍
when would you use an asbury loop and how?
Lol. The old Asbury loop. So all they’re talking about is tying your H2 connection (or the primary neutral connection to the secondary X2 bushing on primary grounded wye systems.) Some places do this. Everyone else doesn’t. If you look at the connection in the lesson, the primary neutral connection and the secondary X2 connection are tied to the same system neutral. So they’re already at the same potential. They’re a no need to make another connection from H2 to X2. This is a topic of debate among engineers and in my opinion I would say there is more of a advantage to not do it than to do it. 👍
@@hilineacademy8482 thank you for explaining it. It seems like over here people think it’s the best thing since sliced bread.
@@mmavoidlol. Ya I hear ya. Pretty much everywhere you go. The utility thinks they invented linework and assume that everyone knows what all their little slang terms mean that only exist there. Keep learning. Stay safe. 👍
@@hilineacademy8482 thank you, stare safe as well! I have line school and a cdl a and I’ve signed the books worked a little bit, but works been slow up here and I’m on book 3 and don’t have a truck or trailer. Any tips on how I should go about trying to get experience despite all that?
@@mmavoid lol. Yes move. There’s a ton of work in Az. Lots of transmission work and not enough men to do it. Call 769 and see what they say. Let them know you have a cdl.
Where does the neutral line go to on the primary side? Does it go back to the substation or does it just go into the ground?
Good question. So it depends on what type of circuit your working on. If your working on a grounded neutral system, the primary and secondary share the same neutral and the neutral goes back to the substation transformer.
If your working on an UNgrounded neutral system the primary has its own neutral that goes back to the substation transformer and the secondary neutral does not. It goes back to the distribution transformer. The secondary neutral will be grounded and it’s localized to the secondary circuits. On these systems we don’t tie the primary and secondary neutrals together. Stay safe 👍
Thanks for the info. That makes sense. Now what about the primary side of the substation transformer? Is there also a neutral line on the grid that goes back to the power plant or is neutral generated at the substation?
Utility companies are ridiculously cheap to save "Earthed wires". The primary Neutral and secondary Neutral shouldn't be tied together at all. It defeats the purpose of an isolation transformer. It should be only allowed to be tied together with " a designated Earthed Wire."
Are two people required when working on the low voltage side of a pad mounted transformer while reconnecting a service that has previously been disconnected and do you have to wear sleeves when working on the secondary voltage side?
To be honest. You’ll need to check with the rule book for the property that you’re working on. When it comes to safety rules you’ll find that the rules change quite a bit depending on the utility you’re working for. Stay safe. 👍
Very well done! Thanks.
Thank you sir. Stay safe. 👍
and the neutrals of the 7200/12470 volt and the 120/240 volt side are connected to each other? And the transformer is local grounded directly below i think
Yes sir. The simulator I built has a grounded wye primary circuit. In that circuit the primary and secondary neutrals are shared. But it’s not like that on an ungrounded wye. On that circuit the primary has its own neutral and the secondary has its own neutral. Then on a delta primary circuit the primary doesn’t have a neutral but the secondary does. So depending on what kind of circuit you’re working on can look quite different from each other both in construction and how you work on them.
god bless you
Glad it helps.
Question please. The circuit neutral (the top wire on your markup)goes back to the substation?
If ONLY one bushing on top of the can, how does the equipment ground go back to the substation? we under multipoint grounded neutral at EACH POLE that has a transformer. We are looking for a PARALLEL neutral system ( multipoint to earth and a separate conductor back to the substation.
So with a single bushing transformer, the ends of the transformer coil connect from the insulated bushing to the pot lug on the case of the transformer, which we connect to the grounded neutral.
Current flow travels from the phase - to the insulated bushing - through the primary coil - and out the pot lug which we connect to the grounded neutral, and returns back to the sub station transformer.
@@hilineacademy8482 Thru the ground. Is this called SWER single wire earth return!
Can you tell us the name of the manufacturer of the transformer in this video?
They were 1/2 KVA transformers that blew up off of a cap bank. But I stripped the cores and rewound them to have a 120 primary coil and a 120/240 secondary output.
is it ok to have 7200 V like that low hanging though?
I appreciate this video sir. Do you have any underground videos I can learn from?
I don’t currently have the setup to do hands on underground lessons but I hope to in the future. If you have any questions don’t hesitate to ask. Stay safe. 👍
How do you decide which phase to use for the primary? Does the utility have to keep the loads on each phase in their distribution balanced i.e. if every pole transformer in the city were connected to the same phase would that cause a problem?
Yes sir. When you get a job from the utility you would look on the print to tell you which phase to feed the transformer with. Stay safe. 👍
I like your teaching technique of using a common item - inches of the discription of the y connection instead of some over the top technical word or phrase. That in itself is more practical and I can understand that more clearly .
when you install the transformer at the customer's place, does the center tap gets connected to the Grid's neutral (the one that runs along 7200V lines). In other words, is there another wire that connects the center tap and the grid's neutral?
Good question. It depends on what kind of primary circuit is feeding transformer. If it’s an ungrounded wye primary circuit the primary neutral and the secondary neutral are separate. The secondary neutral is grounded since it’s feeding homes. The primary neutral is not grounded. It serves to return all of the unbalanced current on the primary circuit back to the sub.
If it’s a grounded wye primary circuit usually the primary and secondary will share a neutral unless they are using it as a static.
I know it’s all kind of confusing but I hope I answered your question. If not please let me know. Stay safe 👍
@@hilineacademy8482 Actually, you answered my question perfectly! thank you! However, in the case of grounded primary wye circuit where primary neutral and secondary neutral are connected, under NORMAL operation, should there be any current passing from one side to the other?
What do you mean by "circuit neutral". Is that the neutral that goes to the house? Thanks
The circuit neutral is the primary neutral that goes back to the sub.
Thanks@@hilineacademy8482
@@hilineacademy8482 May I ask that the secondary (@7:20) neutral is bonded with the primary neutral as well. This connection makes the isolation transformer become an autotransformer. The isolation transformer is NOT an isolation transformer anymore. In my opinion the Primary Neutral and Secondary Neutral should be grounded to earth independently and isolated from each other. Or if lightning hits the power transmission lines , all the surges will go to the secondary side as well and damage lots of appliances and electronics equipment. Please correct me if I'm wrong.
How is the H2 going to ground not energized or is it? Like, I guess the hot primary coming in is at the top of the supply coil and this H2 is at the bottom of the coil but yet it's not carrying voltage yet its continuous with the hot primary coming in? Like, how?
What type of insulation is the on the wire from the cutout to the transformer Tap H1
It’s just covered #6 copper.
thank you Sir !
Any time 👍
Excellent presentation I Have a silly question if the neutral wire is part of the same secondary hot winding why you don't get shocked by touching the neutral wire? i only know current returns to the source via the neutral wire thanks!
That’s a good question. When we get shocked, it’s because we become part of the circuit. Meaning we get in series between two points of the circuit that are at different potentials. If we only come on contact with one part of the circuit, no current would flow through us. We would have to come in contact with another part of the circuit that is at a different potential in order for current to flow through us. So really you can touch any part of a circuit as long as you don’t make a second point of contact with a different part of the circuit. This is how live line barehand work is done. Hope this answered your question. Let me know if you need a better explanation. Stay safe. 👍
@Hiline Academy Thanks a lot for the explanation looking forward to more content!
so I'd assume your setup is most likely energized to 7200/12470. but how are you actually powering this setup on the high side? is there another transformer that takes 120/240 or whatever and bumps it up to high voltages? I am curious.
Great question. The primary is 120/208 3 phase 4 wire. I don’t have three phase at my house so I took 240 single phase and ran it through a phase converter to get 3 phase 240 3 wire. Then I wound a conversion bank that is 240 3 phase to 120/208 3 phase 4 wire. On the secondary side I have multiple taps so I can regulate voltage on the 120/208. Also on all the transformers I use I stripped the cores and bobbins and rewound them to either 120 primary or 208 primary input. And the secondary side I wind to whatever secondary voltage I need. It’s a ton of work. 😓
@@hilineacademy8482 ah, I see. when you do this, do you leave the oil inside the transformers in them? or did you drain it out because this is a demo setup that is probably never going to be on any load.
@ I drained them. It was super messy too. Some of the transformers were blown up and had black soot and burnt oil in them. It was a ton of work to clean them up and strip the old bobbins but yes since there’s no real load on them there was no need to cool them with oil.
If iwant to get three phase low voltage with both three wires connection how can i connect!?
We’ll to create three phase voltage out of single phase transformers, you would need to build a transformer bank out of multiple transformers. Go watch the lesson I did on vectoring. It will give the groundwork to understand where the voltages come from and how to build them. Stay safe👍
Question. Single phase step down transformer ONE Bushing on top.
All the neutrals AT THIS POLE are connected to earth at this location.
We understand this is multipoint grounded (each pole) neutral system).
Where is the distribution neutral BACK TO THE SUBSTATION? thank you
Not sure about 3 cut outs on short arm.
And a piece of equipment. We tend to put equipment on oneside cutouts of power job 3 transformers on the other. Capacitor banks, reclosers, step downsand underground risers... Alot happens when there's a fault and other factors that add to it... Making it a bigger fire ball...
Line wrench works great... Paid by hour
You have combined the primary neutral and secondary neutral with the ground. Now, if the ground wire breaks for any reason, what will happen?
how did you get 7200 volts to the can ?
Question please. 3 phase Wye Wye. Understand the primary is grounded. The question is the secondary coils are NOT in series (as usual)but wired in parallel. Explanation for this ? why needed?
So when your building a 120/208 bank, and your using 120/240 transformers. You only need 120 volts from each transformer.
The 120/240 transformer has 2 - 120 volt coils in series from the factory, which can each output 1/2 of the total amperage that the transformer is rated for (Example: a 25 KVA transformer is good for about 104 secondary amps. That means that each 120 volt coil is good for 52 amps @ 120 volts, and good for 104 amps @ 240 volts if the transformer is in series) so if you leave the secondary coils in parallel and only use ONE 120 volt coil, you aren’t using the total KVA of the transformer. Your only using half. So to utilize the total KVA of the transformer you need to PARALLEL the secondary coils so you are using both of the 120 volt coils to feed the bank. That way you are using the total KVA of the transformer.
If you don’t, the customer will not be getting the total amperage available to them and when their service is at 100% load, the voltage drop will be great, and they will burn up equipment.
To learn how to parallel secondary coils watch the lesson that’s titled “ Alley Cat Bad Dog”.
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@@hilineacademy8482 Clear concise explanation. Perhaps we should mention this when
teaching the subject. Thank you.
Can you please tell me how to calculate, the fuses in the primary for a transformer 600 volts, 3 phases, 75 KVA? Primary Delta and secondary Why.
Thanks.
Enjoying your videos. Dumb question: why is this called a “single phase” hook up when there are actually two 120V outputs that are 180° apart ( i.e. 2 phases)?
Great question. So the term single phase came from back when we used to supply only a 120 two wire services. Phase to neutral. That’s one theory. Another one is that we are only working with one phase angle. Either way it’s just the lingo now lol. Stay safe 👍
Some call it a "split phase.," since you are technically splitting a single phase.
Can I open the canester and take the primary winding in a way to make it where 120v can be step up to 240? . I just got a new old transformer
What is the make / model / manufacturer info for this transformer?
What is your primary voltage?
It’s 120/208 3phase 4 wire. Are you interested in building one?
thanks a lot
Any time. 👍
Where can i buy for the sigle. Phase transformer
Do you mean the transformers I have in the video? If so. I wound them myself.
Do you mean the transformers in the video? If so I would them myself. 👍
Gud day. What if the source of my 220 volt is from 10 kva syncronous a.c. single phase alternator and my actual total load is 18kw. My question is, what type of transformer im going to use??? Please give me advise.
Firstly. If your load is 18kw, and your generator is only capable of supplying 10kva, which is 10kw. You won’t be able to support the load. Using a transformer to change voltage will not help the problem. Higher voltage can push more load, but only if the source generator is big enough. To calculate wattage, the equation is Watts = Volts multiplied by Amps. So if you generator will only support 10kw. You can step up and down the voltage and only change the amps. It sounds like you need a bigger generator. Please let me know if I answered your question. Be safe.👍
why do some single phase transformers require you hook each bushing up to a phase rather than the h2 go to the system neutral
So there is two pieces of info that are required in order to figure this out. First you need to know the voltage the transformer is asking for and the second is to know what circuit voltage and type of circuit you are working on. From these two pieces of information we determine what hookup is required in order to feed the transformer with the correct voltage. I did a video lesson on this exact thing. It’s called “what you need to know”. If you have any more questions let me know. Stay safe 👍
@hilineacademy8482 10 4 thanks for the feedback
In a previous video you said that a secondary connection of this type was "delta." I don't see how that is true since you are using a neutral.
Why is 246V a little high?
Under no load, up to 252 V is normal.
Ya I hear ya. I dont have three phase at my house so I made a simulator which consists of a phase converter that outputs unbalanced 240 three phase and I wound a conversion bank that outputs 120/208. But since the 240 is unbalanced my 120/208 is a little off. I tapped out multiple voltages out but it’s still a little off. That’s what I was talking about.
simple video cody
Thanks Jeffrey. 👍
Ok wait how are you actually feeding that pot? Great video brother. You should try to get your hands on a conventional single bushing pot. That’s what we use on Long Island. The case ground is actually your h2. We make three points of bonding on that connection. Guys seem to think it’s just a case ground but it’s actually the primary return. All around great video though
Thanks for the encouragement. I really appreciate it. I built a mobile simulator in my backyard. I only have 120/240 single phase at the house. So I bought a rotary phase converter which gave me 3 phase 240. Then I hand wound a conversion bank 240 delta to 120/208 wye which feeds my simulator with a three phase extension cord. And I have single bushing transformers at the house. I just haven’t wound the cores for them yet. And yes a lot of people think that the h2 bushing on those pots are just a case ground. It’s pretty scary. I’m hoping that these videos help to educate and demystify transformer hookups. Thanks for the encouragement and if you ever have any questions please don’t be afraid to reach out. Stay safe 👍
@@hilineacademy8482 yessir of course love learning theory. On the Csp pots I e seen guys run the pole ground straight through the h2 lug “case ground” and only make one connection to system neutral. No bueno. If that tap corrodes or comes lose there is primary potential on that tail. We actually make up a 6’ copper lead bend in the middle so it’s a continuous loop with 2 tails. One tail bonds to pole ground pole ground fire Tito system and other tail directly to system. So there is 3 points of bonding. One fails there is two still bonded.
@@linehandibew6205 yes sir. Csp pots can be super dangerous. Keep up the good work. Stay safe.
@@hilineacademy8482 never trust the secondary switch “baker switch “
Me welds on that transformer are pretty good
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Hw much dtr capacity???
Phase to phase is 246
Phase to neutral 123
What is the capacity (kvah)
Are you asking about the capacity of the simulators in the video, or are you asking how to calculate wattage capacity on a transformer?
L1 and L2 are phases on the secondary side
On Primary side H1 is connected to a source but H2 is connected to Earth so why it is not L-G fault in a system
i thought these transformers were 200 pounds..?
Lol not these ones. I drained the oil, pulled the cores and rewound them. They are heavy, just not 200 lbs.
@@hilineacademy8482 Wow interesting
I ONLY WORK ON TRIPLE PHASE
in the real world, all the transformer primary side only have one connection, what's going on?
Lol. I understand. The focus of this video was mainly to understand the process of determining the primary and secondary hookup. There will be more videos out soon on different hookups and applications. Thanks for the feedback. I hope they’re helping to answer some of the questions about transformer theory. Stay safe. Thanks.
That’s a csp pot bud. Try to get outside of your jurisdiction and you come to find what a conventional transformer is. Csp the case ground is your h2 so there is only one primary bushing on the top. On my system we basically use all Csp one bushing pots but the higher kva❤rated pots basically 75kva and up all have 2 bushing high sides. Some systems they have a grounded wye system but on their laterals they run 2 phase delta and all their pot need phase 2 phase voltage. We call them a delta pot h1 to one phase h2 to another given the full phase to phase voltage in this case 7200v
The suplly is single phase 220v. 10kva a.c. alternator and output secondary we need is 50kw. What kind of transformer wear going to use???
baobao question: with one primary bushing on top of the can, do we have a neutral conductor going BACK to the substation? thank you
We understand that EACH transformer (along the single phase, 7200 volt line) is part of a MultiPoint grounded neutral system to the earth.
Those have the other end of the primary coil internally grounded to the can. They're for phase to ground connections only. The kind shown in this video can use a phase to phase primary connection.
Thats because electricians dont work with high voltage
What if ur secondary is 108v hot to neutral and 140v hot to neutral 😅
Sounds like an open neutral.
Pedantic electricians don't like when you refer to L1 and L2 as "phases"
lol. I hear ya. Stay safe. 👍