Talk:Transformer/Archive 10

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Archive 5

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Archive 8

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Dot convention, Parker reference

To 187 for short: In continuation to =Dot convention= section comments above, a valid reason is needed to remove the Parker reference, which cannot be removed arbritarily as now done. If the consensus is to remove it, it will be removed. Valid substantial reasons are needed from you or others, or both. Arbitrary flip-flopping on your part of reference removals and addition is not acceptable and must be done by consensus. As explained EE Portal reference used was not reliable. I invite comments from other editors on this issue. In the meantime the Parker reference will stay.Cblambert (talk) 08:06, 14 April 2013 (UTC)

Mechanical model of a transformer

I have made a file for electrical laymen which could be inserted at the beginning of the "basic principles" section to explain how it works. The basic principles section is rather difficult to understand for somebody who does not know much about electricity. In my comparison model the voltage would be the diameter of the pipe and the current being the speed of the water flow. Because no energy gets lost (except of some heat loss) it becomes clear that the water going in will be the same water amount as going out, just with more speed and the ratio depends on each other.

Here is the text that I would include: A transformer mainly transforms electrical energy. Most of them do it in households where the supply voltage needs to be converted into low voltage. This conversion can be seen as water (= energy) flowing through a pipe which becomes narrow. On the left side the pipe diameter (= voltage) is big (= higher voltage), on the right side it is narrow (= lower voltage). Because the same amount of water goes in and out it has to flow slow on the left side (= supply current) and faster on the right side (= higher current). Some of the energy gets lost because the transformer has thermal losses, indicated by some small arrows leaving the pipe. I think this would be a good explanation, would do you think? RegardsSonk11 (talk) 06:37, 13 April 2013 (UTC)

Probably not. There is already a good mechanical analogy which is gears and gear ratios. Also, I would be against any analogy that suggests energy is a physical substance.Constant314 (talk) 07:19, 13 April 2013 (UTC)

Where can I find this analogy? In Wikipedia? I have some problems in imagining that a gear system can have something in common with a transformer. I find this too abstract for understanding. I have the intention of making the working principle clear to people who do not know about electromagnetic induction. I have asked some people, they did not understand it according to the article, but easily according to the model. Or is Wikipedia only supposed to be from and for experts? By the way I should rather write "transfers energy" instead of "transform".Sonk11 (talk) 11:51, 13 April 2013 (UTC)

The analogy is pretty simple. Torque is analogous to voltage and angular velocity is analogous to current. A 10 to 1 voltage step down transformer would be represented, for example by a primary gear with 1000 teeth and the secondary by a gear with 100 teeth. The output torque (voltage) would be 1/10 of the input torque. The output velocity (current) would be 10 times the input velocity. Power is proportional to torque times velocity so output power is equal to input power. Multiple secondaries are represented by multiple secondary output gears. Outputs can have different ratios. Power can flow from any gear to any other gear. It is not a perfect analogy; it is dc coupled.Constant314 (talk) 16:51, 13 April 2013 (UTC)

This is a terrible proposal. Any such proposal should be used experimented upon using separate article.Cblambert (talk) 18:41, 13 April 2013 (UTC)

Cblambert, which one do you think is terrible - Constant314's proposal or mine? Actually his proposal is a good one because it can be easily understood. The only problem that I have with it is that the step from turning wheels to flowing energy is too far away in my opinion. After somebody understood that how do you do the next step of making him understand? Sonk11 (talk) 00:54, 14 April 2013 (UTC)

Although your illustration is a very interesting analogy it is a poor one, IMHO, because water flow in pipes is used frequently for analogies for voltage and current illustration. I can't get the choke point out of my head as an electrical resistance analogue and the pressure will not change which is usually the analogue of voltage. The gear ox one suggested would be the best if somebody had an animation. 174.118.142.187 (talk) 03:05, 14 April 2013 (UTC)

I agree with Cblambert. A mechanical analog is as likely to create as much confusion as it clears up. It would have to be explained and it would have to be explained how it applies and how it doesn't apply and in the end you don't really understand any better than you did. The Ideal transformer section provides as least as good of an explanation and is more to the point. It might make sense to move that section up nearer to the top where the casual reader can find it. For those that want to to read about mechanical analogs, Google will reveal many such web pages.Constant314 (talk) 05:16, 14 April 2013 (UTC)

This is a Electrical engineering WikiProject with high-importance (see above). Transformer is already probably on the long side as WP articles go. This is not the time to start re-assessing fundamentals. Better to make a real good job of simplifying existing electromechanical aspects. The recent exhaustive review of polarity is a good case in point. The nub of the polarity/dot convention issue hinges on understanding mutual inductance, something which is at the very heart of transformer. No amount of second-guess or analogies from other disciplines or fields can really do justice to such understanding. Better to address the electromechanical issues head-on than to skirt around the periphery in other fields. At Transformer article's relatively mature stage, I would tend to just not try to deal with anything but simplication and honing of essential electromechanical issues. My 3 Canadian cents' worth.Cblambert (talk) 08:33, 14 April 2013 (UTC)

A much better proposal would be for someone to make a proposal to turn transformer article into a GA, which I can't do because I have contributed significantly to the article. Now there's a challenge that transformer is ripe for. Effort needed for GA would likely help focus the issues better than they seem to have been of late.Cblambert (talk) 08:52, 14 April 2013 (UTC)

Thanks for your feedback, Cblambert. Most of the people seem to have the feeling, this idea does not help. I agree it does not make sense to follow up. Sonk11 (talk) 12:38, 15 April 2013 (UTC)

One thing about WP is that someone is free to too just about anything within reason. Feel free to create a new article around this idea . . .Cblambert (talk) 18:02, 15 April 2013 (UTC)

Improvement of explanation for the non-expert

To improve the article for the non-expert reader I suggest the following:

Move the Basic principles section ahead of the history section.

Move The ideal transformer to the head of Basic principles.

Add a section called The linear transformer.

In The ideal transformer retain only the part about the turns ratio and its effect on voltage, current and impedance. Move everything else including reluctance, magnetic field, magnetic flux, magnetic circuit, magnetizing current, winding resistance, counter EMF and Lenz law to The linear transformer.

Improve what remains in The ideal transformer.Constant314 (talk) 18:02, 14 April 2013 (UTC)

First, my first reaction is that this is general a good idea. However, and correct me if I'm not reading this properly, the implication seems to be that there is something amiss with transformer article, that is needs to be dumbed down significantly where it really counts. But the view statistics have been steadily improving of the years so my impression is that the article has been steadily improving.

Second, I don't quite understand the rationale behind 'The linear transformer'. And again correct me if I'm not reading this properly, but not only does the heading's wording seem alien to me, but the implication seems to be that these aspects are somehow slightly sub-standard, second-rate technical content. My view is that all this 'reluctance, magnetic field, magnetic flux, magnetic circuit, magnetizing current, winding resistance, counter EMF and Lenz law' content is of course part of the story that needs to be told as well as anything else of encyclopedian interest to WP.

Third, just for curiosity, where does Equivalent circuit fit in this re-arranged scheme?

Good idea but maybe for the wrong reasons.Cblambert (talk) 19:40, 14 April 2013 (UTC)

I'm not advocating that the article be "dumbed down" or that any material be removed. I'm simply suggesting putting the "easy" material at the top. The ideal transformer has a coupling coefficient of exactly unity. It doesn't have any leakage inductance. Its magnetizing inductance is infinite. It doesn't have any resistance. Its terminal behavior is determined completely by its turns ratio. It is a black box. The section would be entirely about what it does and not about how it works. The next section I think would be the induction law that explains how a transformer works. After that would be a discussion of the linear transformer. A linear transformer has resistance, leakage inductances, etc., but doesn't have nonlinearities like saturation. The linear transformer discussion could be absorbed into the equivalent circuit section and that whole section placed after the induction law. Constant314 (talk) 21:26, 14 April 2013 (UTC)

On that basis, sounds good to me. I am somewhat concerned about putting history section after as it provides a way of easing into the subject but the thought had crossed my mind that the history could come after. I for one support your proposal in principle.Cblambert (talk) 22:00, 14 April 2013 (UTC)

I think highly technical information is good in articles for people that really want to know but.... It really needs to be dumbed down at the beginning of articles for the beginner and younger reader. Starting into the formulae too quickly is a turn off for most readers. They want a bedtime story first and then they can quit or continue into the nitty-gritty of tech details if they can handle it. If not they got what they wanted. Many articles have a second article with top warnings about math levels etc. I am not suggesting we do that here but the placement of some of our formulae may be too soon by placement. For example that "Faraday's law formulae at the top of the article turns me off. I want more story before I get into that study. Perhaps a collapsible bottom section with all the tech stuff we can manage? It may work well and not scare off the non-tech crowd from the article. 174.118.142.187 (talk) 12:45, 15 April 2013 (UTC)

The proof of the WP article pudding is in the WP article view statistic eating. Article should not fight with success. There is overabundance of other sources on the internet available with dumbed-down Pablum content. WP articles need to be as broad-based a possible. Accordingly, the going throughout the article should not be too easy for lowest-level knowledge readers.Cblambert (talk) 17:17, 15 April 2013 (UTC)

The dumbing-down issue is to great extent one reflected in Blaise Pascal's quote, 'I have made this letter longer than usual, only because I have not had the time to make it shorter.' Explaining something technical for lay consumption can take a lot of effort. But I agree that judicial use of collapsible tables is good way to allow drilling to differentiate varying technical subject difficulty levels, as indeed I have used, evidently successfully, in a few WP articles.Cblambert (talk) 19:03, 15 April 2013 (UTC)

Just an observation. It would seem to me that any formulae is not a good presentation thing for non-tech persons. This would mean:

-moving all formulae sections to the end of the article, making the flow progression of the article scrambled, or,

-making all technical formulae collapsible and that would look awful in the prose of the article everywhere, or,

- we do mini duplications of sections again with the tech info in a complete collapsible section at the bottom. IOW the top would read as "dumbed-down" as possible, like a giant lede (multiple) paragraph.

I like the latter concept best but it means dividing a lot of the article already done into two sections and duplicating some. Anybody see another style or another article as a model for a style? 174.118.142.187 (talk) 17:19, 16 April 2013 (UTC)

Constant314 and I are in agreement that there is no need to dumb-down: 'I'm not advocating that the article be "dumbed down" or that any material be removed.' Constant314's plan is start with the easier part first. The ideal transformer. I for one am dead-set on dumb-down.Cblambert (talk) 18:37, 16 April 2013 (UTC)

You may be in agreement but you are putting all the sections with math at the top, contrary to what I perceive as his very point. The article is a turn off for people not looking for a math lesson. Keep the concepts and construction at the top. Math stuff should be in a theory section later for the more hungry tech reader. 174.118.142.187 (talk) 19:32, 16 April 2013 (UTC)

I don't agree. Constant314's proposal is a good one. One has to start with basic principles and build from there. Always as been, always will be. It is called the scientific method. Cblambert (talk) 20:53, 16 April 2013 (UTC)

That is, I don't agree with down-dumbing in general and believe that starting with basic principles seems good approach.Cblambert (talk) 21:13, 16 April 2013 (UTC)

Turn ratio

If turn ratio is good enough for Knowlton, it's pretty good for me. But if consensus is to be more comfortable, even if wrong, with turns ratio, so be it. Let's see a consensus.Cblambert (talk) 06:48, 14 April 2013 (UTC) Re use of n to signify turn ratio, Brenner and hundreds of other references can be found for this. n is used as simple convenient as one would for any mathematical convenience. To object to this is splitting hairs, capricious, and of dubious sincerity.Cblambert (talk) 06:48, 14 April 2013 (UTC)

No splitting hairs and your reference research is flawed or assumed. The original text was the phrase "turns ratio" in all occurrences and you have made the changes without sources to back these up, mixed in with other edits. Please note that the rest of WP uses the term "turns ratio" in dozens of articles, and so does your beloved Knowlton source. The term 'turn ratio' is used in 7 occurrences but also "turns ratio" is used 2 times indicating spelling errors or perhaps the second author:Fowler? inappropriate usage of BrEng for this article. I checked many other references used in this article including the John Winders Book (0 occurrences of "turn ratio", 23 occurrences of "turns ratio"), and the Flanders Book (0 occurrences of "turn ratio", 13 occurrences of "turns ratio"). The Canadian government website defines "turn ratio" as incorrect and "turns ratio" as correct usage giving many references, including:

McGraw-Hill dictionary of scientific and technical terms. -- New York : McGraw-Hill, c2003. xvii, 2380 p.;ISBN 007042313X;

Basic electricity : theory & practice / Milton Kaufman, J. A. Wilson. - Kaufman, Milton. New York ; Montreal : McGraw-Hill, [1973] Symbols and vocabulary words: p. [489]-498.;Includes index

Academic Press dictionary of science and technology / edited by Christopher Morris. --Morris, Christopher G. San Diego : Academic Press, c1992. xxxii, 2432 p.;ISBN 0122004000 as references. See [[1]]

Dictionnaire encyclopédique d'électronique : anglais-français / Michel Fleutry. -- Fleutry, Michel. Paris : Maison du dictionnaire, c1991. 1054 p.;Titre au dos : Dictionnaire d'électronique.;ISBN 285608043X.

I have returned the original prose term to the article. As per WP:BRD you were bold, I reverted, and now the onus is on the initiator (you) to get consensus to change the commonly used spelling of the term turns ratio. Please produce the "hundreds of other references can be found" you refer to and please note the EngVar they are written in. 174.118.142.187 (talk) 03:04, 15 April 2013 (UTC)

Also;

Ratios are never referred to as "n". This is incorrect mathematically and original research by yourself and not welcome in WP articles. These edits were also not supported by your supplied references. It will be corrected until further sources to support this notion can be supplied. Thanks. 174.118.142.187 (talk) 03:04, 15 April 2013 (UTC)

I will go along with 'turns ratio' on basis that usage has evidently won the day.

Brenner reference on p. 508 & 509, Ideal Transformer section says

Current ratio: i₁/i₂=1/n

Voltage ratio: v₁/v₂=n

Driving-point impedance: Z_ab=1/n² * Z_t

I can't believe that someone would not willing to call a ratio a ratio!

But I will dig up the other references showing a ratio can be called a ratio.Cblambert (talk) 04:09, 15 April 2013 (UTC)

In the excellent 2001 reference by RWTH Aachen University Institute of Electrical Machines's Professor Kay Hameyer, "Electrical Machine I: Basics, Design, Function, Operation" there is extensive treatment of transformer turns ratio (including expecially in regarding to equivalent circuits) in Section 3.2, Definition of the transformation ratio (ü) where ü = w₁/w₂. Unfortunately, Hayemer had removed this reference from the Internet.

I had now had the time to take a look a WP:BRD and will digest this shortly.Cblambert (talk) 04:53, 15 April 2013 (UTC)

I guess you will get your way one way or the other on Ideal transformer diagram and n. I don't think it's worth arguing about.

Problem with old diagram:

it can no longer be changed
it shows a transformer under load, not an ideal transformer
it does not show the dot convention.

Which is why I came up with new diagram.

Re use of ratio such as n to mean turns ratio, refer also for example to U. of Alberta Professor Andy Knight's Electrical Machines website http://www.ece.ualberta.ca/~knight/electrical_machines/induction/basics/circuit.html, where he uses the letter 'a' to designate turns ratio. Use of 'a' or 'n' is quite common when used in equivalent circuits to refer secondary impedances to the primary side as done by Andy Knight's webpage. Cblambert (talk) 06:04, 15 April 2013 (UTC)

Just for the record, re use of 'turn/turns ratio', IEEE Xplore search shows that though 'turns ratio' seems to indeed be more common, 'turn ratio' is far from uncommon. I got carried away with Knowlton's official description of 'Turn ratio' being defined as N_P/N_S (which was until then not even fixed, leaving it open for ratio to be N_S/N_P!). It seems clear that 'turns ratio'. Indeed, I myself used 'turns ratio' all my life. Nevertheless, the case is closed.Cblambert (talk) 06:48, 15 April 2013 (UTC)

Excellent Electrical4u website's http://www.electrical4u.com/voltage-and-turn-ratio-test-of-transformer/ refers to Turn ratio.Cblambert (talk) 07:07, 15 April 2013 (UTC)

http://www.federalpacific.com/university/transbasics/chapter2.html Here is another one from FPUniversity showing the following 'turns ratio' as, well, ratios: 2/1, 5/1, 4/1, 2.88/1, 20/1 & 1.73/1. This is hilarious, accusing me of heaven forbid original research!Cblambert (talk) 07:25, 15 April 2013 (UTC)

As Andy Knight does, Electrical4u's webpage, http://www.electrical4u.com/equivalent-circuit-of-transformer-referred-to-primary-and-secondary/, uses K = N1/N2 = E1/E2 to refer secondary values to the primary (and vice versa). No original research there. Different sources use different letter K, u, n, . . .Cblambert (talk) 07:39, 15 April 2013 (UTC)

In Bakshi & Bakshi's book http://books.google.ca/books?id=ghAIqmUX2YEC&pg=SA2-PA15&lpg=SA2-PA15&dq=secondary+referred+transformer+impedance&source=bl&ots=08dpE6FWFQ&sig=gAjou_2APAi8sgrXwQCNpkGLjlE&hl=en&sa=X&ei=saxrUbXuPMbwiwKny4CoCg&sqi=2&ved=0CD8Q6AEwAw#v=onepage&q=secondary%20referred%20transformer%20impedance&f=false K = N1/N2 is used to refer secondary to the primary (and vice versa). No original research here.Cblambert (talk) 07:50, 15 April 2013 (UTC)

Chapter 7 of web.uettaxila.edu.pk/CMS/SP2012/.../notes%5CTransformer.pdf says 'The constant K is called voltage transformation ratio.' However, they define K as N₂/N₁. Wrong way around. Still no evidence of original research on my part here.Cblambert (talk) 08:02, 15 April 2013 (UTC)

http://my.safaribooksonline.com/book/electrical-engineering/9788131760901/1-transformers/navpoint-62 says 'Let the turns ratio be ‘a’.' No evidence of original research on my part here.Cblambert (talk) 08:11, 15 April 2013 (UTC)

Rajput book http://books.google.ca/books?id=k22bKyWqWD0C&pg=PA316&lpg=PA316&dq=secondary+referred+transformer+impedance&source=bl&ots=vE1G_p044h&sig=2isYtW-myoRiYkkYRMFFkZHJ1EI&hl=en&sa=X&ei=k7drUceMC67nigKn7IHwDA&ved=0CC4Q6AEwADgK#v=onepage&q=secondary%20referred%20transformer%20impedance&f=false uses the term 'turn ratio' =N₁/N₂ but seems to then use N₁/N₂ = 1/K in referring values to the primary (and vice versa). No evidence of original research on my part there either.Cblambert (talk) 08:27, 15 April 2013 (UTC)

http://www.egr.unlv.edu/~eebag/Chap%203%20Solutions.pdf uses the example at the very top 'The turns ratio of the transformer is 50:200 (a = 0.25).' No evidence of original research on my part there.Cblambert (talk) 08:35, 15 April 2013 (UTC)

http://www.openelectrical.org/wiki/index.php?title=Referring_Impedances says 'Where n is the transformer winding ratio'. No evidence of original research on my part here either.Cblambert (talk) 08:41, 15 April 2013 (UTC)

http://www.euro-science.com/HOW%20TO%20DETERMINE%20PARAMETERS%20OF%20TRANSFORMER.htm states V1/ V2 = n1/n2 = n. No evidence of original research on my part here either.Cblambert (talk) 08:46, 15 April 2013 (UTC)

http://www.site.uottawa.ca/~rhabash/ELG3311SA1.pdf uses the example 'The turns ratio is a = 8000/ 230 = 34.78'. No evidence of original research on my part here either.Cblambert (talk) 08:51, 15 April 2013 (UTC)

Excellent presentation as www.ee.lamar.edu/gleb/.../lecture%2004%20-%20transformers.ppt says 'Here a is the turn ratio of the transformer.'No evidence of original research on my part here either.Cblambert (talk) 09:00, 15 April 2013 (UTC)

http://nptel.iitm.ac.in/courses/Webcourse-contents/IIT%20Kharagpur/Basic%20Electrical%20Technology/pdf/L-24(TB)(ET)%20((EE)NPTEL).pdf says a = N1/N2. No evidence of original research on my part here either.Cblambert (talk) 09:19, 15 April 2013 (UTC)

Do I need to say more. Echoing what I said at the outset, to object to use of n or similar letter for turn or turns ratio was splitting hairs, capricious, and of dubious sincerity.Cblambert (talk) 09:31, 15 April 2013 (UTC)

In retrospect, a is probably a better letter to use than n because a is less likely to be confused with N1/N2 etc. Like I said, to object to use of n or similar letter for turn or turns ratio was splitting hairs, capricious, and of dubious sincerity.Cblambert (talk) 09:38, 15 April 2013 (UTC)

Well there is some peculiar stuff there. I was always familiar with the term "turns ratio" also, but your injection raised an eyebrow, Why do we use a plural term "turns"?. We say "gear ratio" and yet there are two gears involved. Is it because the are plural turns on each winding and not because of the winding count? What about "tooth ratio"? or is it "teeth ratio"? "Turn ratio" brings to mind vehicle steering where there is not more than one turn of the driving wheels. Is this all nonsense semantics? I really suspect EngVar problems there but everything I found suggests the Knowlton was published in the US. His name is common in British geography though so I suspect he may have been fresh off the boat. LOL. 174.118.142.187 (talk) 12:11, 15 April 2013 (UTC)

I have in my heart very recently come to see 'turn ratio' is the better semantical term, which have been vulgarized with usage to currently more common 'turns ratio'. I don't know what you mean by EngVar. Knowlton is of course American (McGraw-Hill). Knowlton is today's Fink, Fink figuring in Knowlton.Cblambert (talk) 17:05, 15 April 2013 (UTC)

Misplaced aversion to use of commonly used letters 'n', 'a', 'K' and 'ü' for transformer/winding turns ratio definition likely comes from impossibility of sometimes specifying ratios such as gear ratio except as irreducible fraction.Cblambert (talk) 20:55, 15 April 2013 (UTC)

Knowlton was of course handbook's chief editor, article 6-13 that defined 'turn ratio' being authored by V.M. Montsinger, G.E. Research Engineer, and co-authored by W.M. Dann, Youngtown College EE dept professor. Montsinger is very well known and it is unlikely that the definition was grammatical lapse, handbook being 8th edition. I would normally identify a citation down to subordinate author level by did not think it necessary for such seemingly mundate definition. Little did I know.Cblambert (talk) 22:46, 15 April 2013 (UTC)

Funny thing I ran into several brands of "Transformer Turn Ratio Testers". And yet every one of them opened with the phrase "turns ratio" in its lede sentence description. You need to read WP:ENGVAR People get real uptight aboot the variation of English used in articles. I've had my eyes opened few times. 174.118.142.187 (talk) 01:27, 16 April 2013 (UTC)

I have said that I considered the issue closed. The issue was anything but clear and after all is said and done turns ratio is fine with me but turn ratio has been and still is being used.Cblambert (talk) 02:01, 16 April 2013 (UTC)

In post-closure postscript, note that IEEE Xplore yields today exactly '2,969 Results returned' for both search terms 'turn ratio' and 'turns ratio', as in for example the search http://ieeexplore.ieee.org/search/searchresult.jsp?newsearch=true&queryText=turn+ratio&.x=39&.y=11. This evidently suggests that IEEE Xplore does not make a distinction between the two terms.Cblambert (talk) 17:28, 17 April 2013 (UTC)

P.P.S.:Latest available library copy of McGraw-Hill's Std Handbook for EEs is 13th or 1993 ed. by chief eds Fink and Beatty no longer has Knowlton's pat 6-13 turn ratio definition but does maintain the term turn ratio in connection with:

' Voltage ratio is the ratio of number of turns ("turn ratio") in the respective windings.'
' Effect of Turn Ratio: ', with several mentions of the terms.

It would be interesting to see what 15th or 2006 ed. of Fink Handbook. say.Cblambert (talk) 23:51, 17 April 2013 (UTC)

Implementation of plan to improve article for non-expert readers

Per proposal made in previous section, the plan is:

- Move the Basic principles section ahead of the history section.

- Move The ideal transformer to the head of Basic principles.

- Add a section called The linear transformer.

- In The ideal transformer retain only the part about the turns ratio and its effect on voltage, current and impedance. Move everything else including reluctance, magnetic field, magnetic flux, magnetic circuit, magnetizing current, winding resistance, counter EMF and Lenz law to The linear transformer.

- Improve what remains in The ideal transformer.

- The linear transformer discussion could be absorbed into the equivalent circuit section and that whole section placed after the induction law.

First step done today - move =Basic principles= to the top with its ==Ideal transformer== sub-section first, move =History= to the botttom for now.Cblambert (talk) 01:53, 16 April 2013 (UTC)

Step two - Promote =Equivalent circuit= to before =Basic transformer parameters and construction=Cblambert (talk) 18:53, 16 April 2013 (UTC)

Step three - Create 'The real transformer' sect. & 'Real deviations from ideal' sub-sect w. content consisting of re-wording last part of 'The ideal transformer', promote 'Leakage flux' and 'Polarity' Cblambert (talk) 04:56, 17 April 2013 (UTC)

The Real Transformer section is a good idea, but the last item which starts with "Since the ideal windings have no impedance" seems to be incomplete. I think it should say something like "the windings in a real transformer have a finite non-zero impedance".Constant314 (talk) 12:54, 17 April 2013 (UTC)