How to wire a transformer in series or parallel (with animation) | Basic Electronics
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- Опубликовано: 7 июл 2024
- Working with transformers isn't that hard to do yet there may be something intimidating about dealing with a device you plug into the wall. We take this opportunity to very briefly cover how to wire a dual primary and dual secondary transformer in series or parallel. You want to be able to wire the primary side of the transformer based on the incoming voltage (115V in some parts of the world, 230V in other parts) and wire the secondary side based on your desired outgoing voltage (12V or 24V with Triad Magnetic's VPS24 that we use in our example - check out their datasheet for more info: catalog.triadmagnetics.com/As.... As always, take your time, make sure you know what you're doing, and if you're not confident, ask for help.
We want to thank Triad Magnetics, one of our Friends of CircuitBread, for supporting this tutorial! Check out their site at triadmagnetics.com to see what other transformers and magnetics they offer besides the VPS24.
We also created a written tutorial based off of this video that spends a little more time on the polarity dots of the transformer and can also be read at your own pace: www.circuitbread.com/tutorial...
Table of Contents:
0:00 Introduction
0:22 The need for a dual primary and dual secondary on your transformer
0:42 What a transformer looks like in schematics
1:34 Why we would want transformer input or output in series or parallel
3:02 The steps of how to setup the transformer in series or parallel - from the very beginning
4:22 How these steps would work on a different type of transformer
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Good news! Triad Magnetics, one of our Friends of CircuitBread, is supporting this tutorial! You can find the datasheet for the transformer used in this tutorial at catalog.triadmagnetics.com/Asset/VPS24-5400.pdf and you can check out their site at triadmagnetics.com to learn from their transformers and magnetics knowledge. We want to publicly thank them for supporting this free educational content!
"I'm absolutely positive." [POOF] ...and the magic smoke appears. Been there. Enjoyed the video. Thanks.
😂 Thanks!
Very helpful and clear summary of dual primary / dual secondary transformers. Thanks.
Hi all! If you want the static images to look at and compare with whatever you're working on, we made a written tutorial using the images in this video that you can check out here: www.circuitbread.com/tutorials/how-to-wire-a-transformer-series-versus-parallel
Could I ask for advice on how to make a step up transformer? 65 VAC To 240 VAC. There are only two wires on these microwave oven transformer coils. One wire is hot. And one coil is neutral. Does it matter if one or the other is on either the top or bottom side of the left side of the step up transformer coil?
@@user-kg6eo8dm6v Sorry, just noticed this! If you're using a transformer with only a single winding on each side (which is what it sounds like) then you can imagine that it's like the transformer used in the example but with the bottom (or top) half chopped off. In that case, you only care about which side has more windings than the other. If you have the tools to test it at lower voltages and higher impedances (so you don't hurt yourself - always top priority) you can put a signal in and see if you have the inputs setup properly and modify it if not.
straight forward clear explanation totally got it
From Hammond transformer company. You must hook up the dual windings type transformer in phase or you will burn out the unit. In transformers with dual primaries and secondaries, do I need to hook up both? YES, The unit was designed to run both and if you use just one it will overheat and voltage regulation will be poor. In dual winding transformers, how do you hook windings up "IN PHASE"? To hook the windings in parallel, always hook the dot to the dot. To hook the windings in series, always hook the dot to no dot. This applies to primary and secondary windings.
simple, straightforward explanation. THANK YOU
Thanks for watching and leaving a comment, Juan!
Wow! Thank you. Very clear and concise.
Thanks, glad it helped!
Excellent information best teacher with super voice.
Thank you for your good informative and useful video🎉❤
Your videos are short and succinct. I like that.
Thanks! Sometimes they're shorter than others but we at least *try* to be straight to the point. And if I start to ramble, Taylor can be aggressive in his trimming. 😀
Transformers, higher voltages in disguise.
Well done
Briliant idea thanks
Thank you!
You have a voice and attitude that is very conducive to relaying information. Keep up the great work. I'm starting some electronics project with my son and he will love this video. Liked and Subbed.
Thanks Aaron and that's awesome to hear about the projects you'll do with your son! I need to be better about doing projects with my own children. I hope you have a great time with him and it's something he remembers forever.
Dont get demotivated
U are best on youtube
1million subcriber soon
Aye rupali aye rupali pakad meri daali aye rupali banau tujhe rani
Very helpful video, thanks. I am currently building a power supply, and intend to use an old transformer (no datasheet) that has dual (115V/220V) primary windings. I have identified the windings from a continuity perspective, but cannot work out the polarity/phase aspect. There are a couple of comments below emphasising the importance of getting it the right way round, but how would I go about identifying which end of the winding is which? Thanks.
Well explained and admittedly, a little beyond my expertise. I have an unrelated question you likely can answer:
I have installed a backup irrigation controller. Both the primary and backup controllers use a 24vac transformer (1000ma each) and a changeover switch allows to switch irrigation from one controller to the other. I am short one terminal on the changeover switch. So my question is can I safely combine the Common wires from each 24v transformer without introducing any back feed? Or, should the Common wires be isolated from one another?
Hi, thank you for the video. I have a question. I have a toroidal transformer that is 500va, 36 volts. I have tried to connect the secondary windings in parallel (I have done this with other transformers without problems) and it shorts for some reason.
What could be causing the problem please?
Many thanks
Is this why I have to bypass the power meter to fire up 7 12kv nst's running in parallel pri's? You don't need multiple primary windings if you share the common on all the transformers and series the outputs by tapping the common out to the core then hot out to the next core and so on till end using final trans hot live and first case as common. Does the same thing
Thanks for the great video! Very educational and helpful. Could you please provide a link for the type of wires you are using to make the connections? Thank you.
I literally just bought some wire from Home Depot, it wasn't anything special. As long as its rated for the current and voltage expected, you should be fine with whatever wire you have on hand. Good luck with your own experiments!
Thank you i suspect it but you gave the solution
thank you
Background tools are good 🤩
Haha, thanks! We actually just posted a video going through many of those tools. When we modified my office to make it more video friendly, the video guys re-arranged them to "look better" but it's more or less how I had them in the first place.
Best videos
Brilliantly done! Is the colour coding on the outputs of a toroid standardised as in your example (4.28)?
Thank you! And I don't know but I would not think so. Either way, I'd always check the datasheets for each transformer rather than just assuming.
Good video... i've got a 110v FW Bell 620 Gauss meter... read the specifications and 220 was supposedly supported... (too late after i've noticed that if you rewire the primaries)... i've burned it... what actually happened ... and what to do next to fix it? thank you
It's impossible to tell without being there (and I'm not a repairman so I'm not sure if I'd know even if I were there) but it would probably be best to hope that it was only the power supply portion of the Gauss meter that was burned. The 620 says it has solid state construction so hopefully it was the AC/DC converter portion that burned and that could be replaced with a new transformer and some rectification circuitry or, ideally, a new power supply in general. You probably want to reach out to F.W. Bell directly and see if they'd be willing to provide either some advice or documentation.
Hi there sir and thank you for this information, I do have a question whenever you can reply is going to be helpful and I'll be thankful for it .I will try to post a picture of it after this comment because I don't see an option at the same time, some info: it is 120v primary, 1st sec. 12v - 2nd sec.2.55v, it says in label, I need help identifying each number of pins and if I can and how to get 35v out... 3 pins on primary size and 5 secondary size
Can a function generator be used to substitute a transformer in making a little full-wave center-tapped rectifier with two diodes? Thanks!
For testing and very low-load stuff, it should work. Function generators have fairly high impedance outputs and limited voltage range (depending on your generator) but we've used them successfully to do some testing while trying to avoid dealing with line level voltages.
U the best 😊
Happy Holidays. One question you might help me with. I have two standard 2000 watt 220v to 110v step down transformers. Is it possible to wire these two transformers in parallel to achieve a 4000 watt 110v output to run an air fryer? Or must I purchase a 5000 watt step down? The devise recommends 3000 watts. Thank You
Hey Burt! If your transformers are properly matched and wired, then you *could* wire them in parallel with a common ground and it *may* not have any problems. But it makes me extremely nervous and I strongly recommend you don't do it. With something like this - relatively high voltage and high power - I'd avoid any homemade solutions that are using the components outside of their intended usage. It's not worth the potential for electrical shock or a house fire.
Hey, thanks for the video. I took a step away from electronics for several years, and I am getting back into it. Seems I'm a little rusty. I got one of these transformers (or very similar), and wired it up the same way as you did, but as soon as I connected power, it popped with a flash and a trip of my breaker. Does this sound like a short circuit somewhere to you too?
Darn, that does sound like a short circuit. It could be that the transformer was bad in some way (holes in the protective layer of the magnet wire are unusual but possible). It's also possible that the transformer looks very similar but that the manufacturer has the connectors placed differently. What transformer is it?
This setback is unfortunate but it is awesome that you're getting back into electronics! Letting the smoke out of things is just part of the process.
@@CircuitBread yes indeed! It's this one - uk.rs-online.com/web/p/products/0504252/
I think I may have accidentally made a connection with the box and the outer casing, which was earthed. Does that sound pheasible?
That does sound feasible and it would explain the breaker being popped. It would also mean that, most likely, your transformer is still fine, as the excess current didn't actually go through the windings themselves. If you put a multimeter across the leads (test across the primary side and then test across the secondary side) what are you reading for your DC resistance?
Thank you first. What will happen if we apply voltage (115v) to the one of the primary winding? Will output voltage change as a value?
Yes, the input and output are related via a ratio. For example, if it's rated for 120V in and 12V out, then it's a 10:1 ratio. Putting 100V in would yield 10V as the output. Of course, load and all that changes things as well (we have another video talking about why there is some "hand-waving" in that ratio) so it's not exact but, generally, that's correct.
From Hammond transformer company. You must hook up the dual windings type transformer in phase or you will burn out the unit. In transformers with dual primaries and secondaries, do I need to hook up both? YES, The unit was designed to run both and if you use just one it will overheat and voltage regulation will be poor. In dual winding transformers, how do you hook windings up "IN PHASE"? To hook the windings in parallel, always hook the dot to the dot. To hook the windings in series, always hook the dot to no dot. This applies to primary and secondary windings.
I'm taking a class in stationary machinery (transformers) and I've been looking for one I could experiment with at home to hook up in Delta and WYE configurations. Would the one used in this video be a good one to work with?
As you can hook the primary in series or in parallel, I think it would be good. You could probably get away with a smaller transformer, though, as this one is quite big and heavy. It's been long enough that I don't remember how much it cost, but I don't remember it being inexpensive, so something smaller would also be cheaper. But you'd want to make sure you're still getting one that has the ability to put it in series or parallel.
@@CircuitBread Mouser has it for 27.62 and I can afford that. As to being heavy... well I can always use it as a paper weight :)
Thanks.
Here's the question: Having that 2 winding input 2x 120V transformer and you want to add a selector switch so you can use the transformer on both Europe (240V) & US (120V) you'll need a 2way/6pin rocker or sliding switch. What's the wiring schematics to that? This maybe sounds simple but for me it's kinda confusing. So I need to connect the 2 windings together in series to get 240V but also 1 winding to get 120V.
This answer is probably not relevant to the OP, but for other readers my advice would be to consult the service manual for equipment that has a dual voltage switch. E.g. the service manual for the TEAC AG-790 (available free on line), has a wiring schematic in the power supply section.
Is it possible to make some kind of circuit by using 1+2 and 5+6 separately, instead of connecting the two "sub-transformers" together? For example connect a circuit across 1 and 2 and not chain it to 5 or 6.
Yep, totally possible!
i'm making an electromagnetically-powered clock project. i'm not sure what volts will work best because i've been experimenting with different magnet-coil configurations. i got a 240in transformer with 6v / 6v outputs. can you show me how to connect for 6v low-amp; 6v more amps; and 12v pls. ALSO: i'm switching the low-volt side with a hipp trigger which utilises motorcycle contact breakers, will the breakers last longer with ac or dc ?? thx
Hey Raymond, I'm curious to see what this project turns into! Without seeing the spec sheet for the transformer, I can't provide any specific feedback on where you should connect things. But 6V low-amp would just basically be only using one half of the secondary side. Using the transformer in the video as an example, that would be similar to just tying to 12 and 11. To get more current, you would put 12 and 11 in parallel with 8 and 7. And if you want 12V, you'd tie 8 and 11 together and then use 7 and 12 as your output.
As for switching, I'm not familiar with those contact breakers. But if they're like thyristors, they turn off when the voltage is 0, which makes for a clean break. So AC has the potential of being less punishing to the breaker. But... especially if the voltages and currents expected are low, it really shouldn't matter that much.
@@CircuitBread hi. thx for the reply the last bit may well prove crucial !! Here's a link to the project - it's still ongoing in the search for reliability and has changed a bit since the video was made. at 1:06 you (just about) see the contact breakers, from a 1980s suzuki motorcycle, are you too young to know vehicle contact breakers? blimey i'm soooo old. i'll open up the coil box (0:24)and remove the diode matrix - i have a good feeling about this, now. thanks boss
ruclips.net/video/v29zvTK50yw/видео.html
Is it possible to get for example -15v and +15v out of a transformer like that or do you need a different winding setup?
If you set up the output in series, then use the center-tap as your ground/neutral point, then setup a full wave rectifier on both the "top" and "bottom" of the transformer, one to give you a positive DC signal and the other to give you a negative DC signal. I've never done this and am now trying to think through if this makes sense... Actually, I'm thinking that it shouldn't even be necessary to use the center-tap but just setup the two full wave rectifiers up on the same output and connect the positive output of one to the negative output of the other. There actually seems to be a couple of different ways to approach it and it has much more to do with the rectifying circuit than the transformer itself.
@@CircuitBread Thank you. I didn't get notified of your replied and ended up seeing it three months later...
I am using the same transformer and somewhat worried about the high current there will be on the seconday side (almost 11 Amps). What do you recommend if I plan on lowering current down to mA range? Should I just use resistors that are rated at high current/watts?
Current is dependent on the load - if your circuit on the other side can handle the output voltage, the transformer will only provide enough current to supply the load. No more than that. I'm not sure if that's clear enough, so let's try a different tact. With Ohm's Law, the best way to think of it is V/R = I. You can control the voltage and resistance, the current is just a result of that. If your output voltage is 12V, if you have a 12ohm resistor, your current will only be 1A, even if the transformer CAN supply more. Let me know if I'm understanding the question correctly and if that answer actually helps!
@@CircuitBread Yes that makes sense. Thank you so much!
Dear Sir, I'm trying to use to two sets of two microwave oven transformers which are wired together in parallel. These four coils cumulatively produce 65 volts total..........I want to step this 65 volts up tp 240 volts....................Is there a difference if the top or bottom of the transformer are connected to the hot? or neutral?
It is always best to rely on the data sheets of the transformers you’re working with. While transformers are theoretically not polarized, manufacturers may add protective circuitry or optimize them somehow to be used one way versus another. As always, particularly when dealing with mains voltages, please be careful, err on the side of caution, and consult a professional locally if you’re not familiar or comfortable with the situation.
+KDKK Gamer is right: DON'T allow yourself to get discouraged or give up. Virtually every "name" in RUclips started out in the same slog, and digital marketing/developing a personal brand is... actually, it's a lot like wiring a transformer. Take your time, be patient, do it right, make sure you're putting everything where you're supposed to, and ensure you don't overlook the value of solid connections. I've been a web software engineer for 25 years, and, while I'm entirely cognizant that I lack both the charm and personability to be a "personality", I HAVE worked with a great deal of them.
Not to put too fine a point on it, you DO possess the charm, the personality, the likability, the clear, concise, measured delivery/voice... you can absolutely succeed at this; this first bit just sucks and will feel thankless and pointless. Just know: it is not. Cover the basics (like you did here), even if it seems like stuff everyone knows. Trust me: they(/we) don't. After you've covered the fundamental parts and components, and then the basic implementation configurations, start to sprinkle in simple, amusing, and above all, accessible projects. Get your audience to learn from you, establish trust, then get them to do with you. After that? Then you get to the fun stuff.
Like anything else, it's all about paying your dues, working each step/solution, and, above all else, NOT. GIVING. UP.
Liked, subscribed, bell'd. I look forward to watching your progress!
Wow, Jason, I don't know what to say. Thank you for this message, it means a lot to me and the entire team. We have definitely had our moments of questioning what we're doing, especially from a business standpoint, but we've always overcome it just because we're passionate about it. We love education and helping others understand things that were difficult for us when we started. Getting this is extremely motivating and means that we're on the right track - thank you again!
I have 3 wires on my secondary.
Hammond part # 166L25
Green , Green/yellow, Green
Is the Green/Yellow common?
They gave me two secondaries?
Could I not have just run an extra wire to a single secondary to run my two items?
Looking at the specs, it does look like the green/yellow is common, it's probably setup to be used in a center-tapped rectifier circuit ( www.circuitbread.com/tutorials/center-tapped-full-wave-rectifier-operation ) So, depending on what you're doing, you can tap on the two green wires to get the full voltage or one green one green/yellow wire to get half the voltage output. I believe that you can just ignore the green/yellow if you don't want it - perhaps put a wire nut on it. Again, it depends on the application.
@@CircuitBread Perfect thanks. This explains it. I see it does say it is centre tapped. I need 25v so I will wire the solid greens together and cover the Green/ Yellow with a wire nut.
Very clear explanation but what do I do to get split phase where one phase is exactly opposite of the other like the US 240 VAC system for large appliances?
Hey RAM, without some special equipment, the only way to get that 240VAC is by tapping into the incoming power from the power line. Generally, it enters the house at 240VAC and then, in the breaker box, is split and sent to the different circuits as 120VAC. So, if you jump into your electrical box directly, and run the wires with both phases, you should be able to get 240VAC to wherever you need. However, at that point it's an electrician thing, not an EE thing, so please talk to an electrician for more details before trying anything.
@@CircuitBread I am aware it enters the the house at 240 VAC but how does the 240 VAC line become two 120 lines in exact opposite phase of each other? Large US house appliances literally have two 120 lines going into them opposite of each other. Does the center tap of the secondary coil automatically create the opposite phase? For example in your video I join 1 and 6 to a single phase 240 line and I connect 2 and 5. On the Secondary side I join 11 and 8 to a single wire extending out like a neutral wire. 7 and 12 become the two hots .. Will that give almost the same result as the US large appliance 240 split phase power supply?
Hey RAM, I'm not sure if the confusion is visualizing how the 240VAC in the breaker box is the same as two 120VAC sources out of phase (like in this image: images.app.goo.gl/wrRvYQdwvAj3ABY58 ) or if the confusion is in your attempts to recreate it. But your statement that the center tap automatically creates the opposite phase is correct. I'm trying to think of the best way to describe how it works visually and frankly, I'm failing. If I come up with something inspiring, I'll jump back on and mention it.
As for your setup, looking at it, and if you have a 1:1 transformer, you should be getting two 120V outputs out-of-phase, just like the different rails in a typical house electrical breaker box.
@@CircuitBread The image you posted is what I am aiming for. On the 120 volts side the two 120 Vots phase will be opposite of each other like the blue and red lines in the image ?
sep.yimg.com/ty/cdn/yhst-14463325294384/Electric-240-Volts?t=1594326450&
If so then my next question is how would I determine the Amps capacity of the primary and secondary coils? From what I understand the ratio of the number of loops on the primary side and the number of loops on the secondary side determines the voltage on the secondary side(for example primary has 120 and secondary has 60 each makes the secondary voltage half of the primary). How do I determine the Amp capacity? Do both sides have the same AMP capacity?
Hey RAM - the amps capacity is just a rating you'll have to get from the transformer data sheet. As you're looking at a 1:1 transformer, they will need the same amps rating on both sides, though that isn't true for transformers with varying turn ratios, as they only need to match *power* ratings on both sides in that case. Of course, with a 1:1 ratio, both the amp and power rating should match on both sides.
Unfortunately, that image link didn't work for me, so I can't confirm what's going on there. But you are correct that the number of loops is what drives the voltage differences between the primary and secondary sides.
Can this type of transformer be used in reverse as a step up transformer?
Though transformers are usually designed to function in one direction, with a specific primary and secondary, they can be driven in reverse. If the transformer isn't designed specifically for that - it'll likely have some losses and voltage ratings may not be the same, but if you're careful and avoid the extremes of the transformer tolerances, it should work fine.
Prints and Schematics must be used for our beloved homes as well.
Very straightforward explained. Even a moron can get it . Superb
Thanks Arafat!
Hi CircuitBread! can you make A centre tapped full wave rectifier..............Though your efforts are appreciated
Hi Noorul! Already done - check out the written and video tutorial here: www.circuitbread.com/tutorials/center-tapped-full-wave-rectifier-operation
@@CircuitBread thanks
Can you do one for 14 pin transformer
⭐⭐⭐⭐⭐👍
what if I want 12v and 24v out at the same time?
With this particular example, the problem with wiring the secondary in series (for 24V) is that it would short the wires that are connected in parallel (for 12V), meaning that each output pin would be shorted together. I'm not sure if they have transformers designed to output in both series and parallel at the same time, that would be interesting to find out.
@@CircuitBread I asked hammond manufacturing, and was told(using your example) that connecting 8,and 11, and using it as a center tap, gives you the ability to output 12v,and 24v concurrently, however the two voltages won't be isolated from each other. I have been looking for videos online to confirm this, but haven't found any. (hint, hint) :)
Haha! I get nervous around voltages higher than 5V (long story), so I'm not very experimental with transformers. I'll have to see if one of the other engineers would be interested.
What happen 1&2 are connected?
It's just short circuited, so there won't be a voltage across the leads. There won't really be any current that flows through the bottom left coils themselves, as the coils will be a higher resistance than the wire connecting 1 and 2. It most likely won't hurt the transformer, but it won't do anything useful.
I have a transformer with 14 pins how do i use that
In summary - I have no idea. I was hoping that this video would show the concept that could then be applied to other transformers. I would have to look at the datasheet and try and make some comparisons before I would be able to make any guesses on how they operate. Without that datasheet, though, my assumption is that there are center tap points and potentially some pins that don't really do anything too functional. But I don't know.
I tried to find the data sheet but i coudnt find it problablt becouse its from a radio
Oh, dang, that does make it tough. Interesting challenge, though. It depends on your intent, but if you have a multimeter, you can start trying to figure out how they're all related. It would help even more if you had a sine wave generator and oscilloscope (though I realize these are not as common to have as multimeters) and you could mess around with it quite a bit.
I wil try it and hope i will figer something out i have a multi meter but i dont have a oscilloscope or sine wave generator
Why i blow tow transformer whit this method ?
I realise that this video is geared for North America, 120V (60Hz) Again I have an American Radio Shack industrial stereo PA amp that puts out 250 W per channel. I want to convert this to receive 230V (50Hz) as I plan on bringing this back home to Europe. I am assuming it is an easz chore to do. As I am dealing with nearly twice the imput voltage i of course do not want to fry my USD 200 amp to smytherines!
Hey Nikolaos, changing the voltage from 230V to 120V for your amp would be pretty simple - there are even off-the-shelf options that are relatively inexpensive (and just have a transformer in them, very simple to use).
The part that concerns me is the 50Hz. When I lived in Japan, most all of the US equipment we used was fine with 50Hz, but some stuff just didn't work quite right (hair clippers, for example). That being said, our AV receiver did work just fine so... I *believe* that your amp will be fine with receiving 50Hz when expecting 60Hz but I don't know that for sure and it makes me a bit nervous making promises.
Pri ^^ 120v, ov(no.2-3)
class 2 , 60hz
35DA507
77202 - 0057 - 00
Sec,1(NO.7-8) sec, 2(NO.4-5)
12.8v, 3.84VA ---. 2.58v o 348VA
DY 5. 15W ..... This is all the information on label please and thank you
No mention of the big dots shown on schematics? Tsk, Tsk....ignore the "sense" of transformer windings, as indicated by them, at your peril. Sure, a new transformer purchase will already have a recent datasheet or reference to data, showing at least how to wire it correctly according to a schematic with possible configurations but not for the old transformers in your collection, which you probably need to use instead. That's when folk really could need some help with safely determining this missing info.
We definitely do need to go back and do a "basics of transformers" to cover several other items including those dots and what they mean. We have a few more transformer videos queued up but, frankly, I'm falling behind, so I'm not sure when I'll get to them.