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Why is the Transformer article not stabilizing like other mainstream electrical articles?

Although transformer technologies and products are relatively mature, the Transformer article is at archive 12 with no indication that pace of editing is tapering. Why is it that the rate of editing of the Transformer article is not stabilizing like it is for other mainstream electrical articles?Cblambert (talk) 05:38, 25 May 2014 (UTC)

The Transformer article is not stabilizing to a great extent due to sub-standard editing quality, which will likely not improve until the article progresses gratually from "through its lifecycle, preceded by others such . . . peer review, good article, and finally featured article status." WP:STABLE Cblambert (talk) 23:47, 4 June 2014 (UTC)
Another factor contributing to low-quality editing is rampant satisficing when editing is not tempered by critical mass of higher quality editors. Cblambert (talk) 06:33, 5 June 2014 (UTC)

Ideal Transformer Loss

I would delete the lines about copper loss and inductive loss. The preceding line says that there are no losses. There is no need to itemize the losses that are not there. Constant314 (talk) 22:27, 26 May 2014 (UTC)

How about the following?
The ideal transformer is a theoretical, perfectly-coupled, linear transformer devoid of energy losses; that is, a transformer in which windings have no resistance and core does not manifest magnetic hysteresis or eddy currents; flux is confined within the magnetic core; core's magnetic permeability is infinitely high, implying zero net magnetomotive force (Amp-turns) (otherwise there would be infinite flux), and hence IPNP - IS NS = 0; and no current flows in the primary winding when there is no secondary winding load.Cblambert (talk) 23:43, 26 May 2014 (UTC)
When you tell the reader that there is no resistance, magnetic hysteresis or eddy current you are tacitly assuming that the reader knows what those things are. They aren't defined until later in the article. At this point in the article, I think it is better to say only that there is no loss without listing those losses that would present in a non-ideal transformer.Constant314 (talk) 00:37, 27 May 2014 (UTC)
I propose then as follows:
"The ideal transformer is a theoretical, perfectly-coupled, linear transformer in which:
I support that.Constant314 (talk) 01:22, 27 May 2014 (UTC)

"I propose changing 1st paragraph to read:

The ideal transformer is a theoretical, linear transformer that is:
Perfect coupling implies infinitely high core magnetic permeability and zero net magnetomotive force (Amp-turns) (otherwise there would be infinite flux), and hence
  • IPNP - IS NS = 0, and
  • no current flows in the primary winding when there is no secondary winding load."

so as to completely define the ideal transformer in terms of it being lossless and perfectly coupled.Cblambert (talk) 18:56, 28 May 2014 (UTC)

I think that there may be some confounding of two ideas here. An ideal transformer is defined entirely the voltage and current ratio. Vsec = n Vpri and Isec = Ipri/n. These two equations are enough to conclude that there is no loss and perfect coupling. I’m not sure there is justification to even say that there is a core.
On the other hand you could start with a linear but not ideal transformer and ask how would you change it to turn it into an ideal transformer. If you can take limits as the copper resistance and leakage inductance goes to zero and as the permeability goes to infinity you could show that the linear transformer could come as arbitrarily close to the ideal transformer. It would be a justification of the ideal transformer.
But maybe it doesn't matter.Constant314 (talk) 04:52, 29 May 2014 (UTC)
Brenner & Javid (B&J), Analysis of Electric Circuits, say an ideal transformer is a lossless, perfectly coupled transformer whose inductances is infinite but whose inductance ratios are finite in such a way that
(see B&J pp. 598-600)
I am not sure how to translate that in lay terms here but this finite inductance fraction value is tied in fairly closely to leakage inductance article. I will sleep on this a day or two.Cblambert (talk) 07:00, 29 May 2014 (UTC)
I’m thinking about it also. I do not think that infinite core permeability implies zero leakage inductance. I am considering of a rectangular core with both primary and secondary being wound on bobbins. The primary bobbin is on one of the long sides and the secondary bobbin is on the other side. There is a gap between the windings and the core and since the B field is continuous there will necessarily be B field in that gap and so there will be a non-zero leakage inductance, even if he core has infinite permeability. Constant314 (talk) 21:49, 31 May 2014 (UTC)
If I wanted to minimize leakage inductance, I think that I might start with a ferrite core and then plate the windings directly onto the core. Constant314 (talk) 21:49, 31 May 2014 (UTC)

I think that you are going about the ideal transformer backward. You do not need to derive

because it follows directly from IPNP - IS NS = 0.

A transformer is fundamentally a magnetic device so current ratio is more fundamental than voltage ratio. You can combine current ratio with the ideal transformer being lossless to derive the voltage ratio. Constant314 (talk) 01:42, 6 June 2014 (UTC)

We are in this together. Until a few months ago, the reference to IPNP - IS NS = 0 did not exist.
The ideal transformer is indeed by definition defined as a 2-port network that behaves according to , this without reference to magnetic coupling or permeability or anything else magnetic. Which is essentially the way it was a few months. The ideal transformer is by definition a constant voltage device. There is no difference in important between voltage and current between the two. Cblambert (talk) 02:53, 6 June 2014 (UTC)
Well ok it is magnetic to the extent that it is perfectly coupled etc. But there is no sense getting too hung up on any one particular espect. As long as the whole is consistent. The ideal transformer is after a theoretical construct. Derivation of ideal transformer identity is exactly as shown. One can quibble with a bit of redundant but the section is entirely defendable in my view. Cblambert (talk) 03:42, 6 June 2014 (UTC)
Change done make to article to make consistent with first equation in Ideal transformer se4ction.Cblambert (talk) 04:38, 6 June 2014 (UTC)

The ideal transformer needs two assumptions. Since it is a two-port, that is no surprise. You can choose:

1. losslessness and voltage ratio to derive current ratio.
2. losslessness and current ratio to derive voltage ratio.
3. voltage ratio and current ratio to derive losslessness.
4. losslessness and perfectly coupled infinite permeability to derive current ratio and then voltage ratio.

Perfectly coupled infinite permeability is equivalent to Is/Ip = Np/Ns. If you make three assumptions, one of them is redundant. So, I suggest pick two and derive the rest. As to which combination, I lean two ways. The first way is to simply deny that the ideal transformer has any internal structure and then remove everything about permeability and coupling and pick 1, 2, or 3. You would probably choose #1.

However, even though I think imputing an internal structure to the ideal transformer is foolish, it is intuitively appealing to say that ideal transformer is the limit of a linear transformer as you hold the turns fixed and let the permeability go to infinity, the leakage inductance go to zero and the losses go to zero. In that case, it is possible to prove that Lim( NpIp - NsIs ) = 0. It gives an intuitive reason that Ns/Np matters.

Maybe we should start an Ideal Transformer page.Constant314 (talk) 18:06, 7 June 2014 (UTC)

Explanations for the rapidly declining view statistics?

Referring to Transformer article's view statistics detailed below ,expressed as 6-month moving average, I invite comments as to reasons why view stats have declined by 40% compared to peak in March 2013.

6-Month Moving Average Tabulation
Yr-Mo 6-mo.-avge Views Percent of peak Comment
2014 May^ 119,336 60.3% ^30 d. to May 26
2014 Apr 124,911 63.1%
2014 Mar 131,015 66.2%
2014 Feb 128,781 65.1%
2014 Jan 130,256 65.8%
2013 Dec 134,638 68.1%
2013 Nov 141,374 71.5%
2013 Oct 147,232 74.4%
2013 Sep 153,320 77.5%
2013 Aug 167,332 84.6%
2013 Jul 178,533 90.2%
2013 Jun 188,465 95.3%
2013 May 191,289 96.7%
2013 Apr 194,555 98.3%
2013 Mar 197,829 100.0%
2013 Feb 191,674 96.9%
2013 Jan 184,786 93.4%
2012 Dec 176,036 89.0%
2012 Nov 172,678 87.3%
2012 Oct 166,993 84.4%
2012 Sep 156,854 79.3%
2012 Aug 156,737 79.2%
2012 Jul 156,418 79.1%
2012 Jun 157,160 79.4%
2012 May 154,152 77.9%
2012 Apr 152,788 77.2%
2012 Mar 151,199 76.4%
2012 Feb 143,527 72.6%
2012 Jan 142,002 71.8%
2011 Dec 145,215 73.4%
2011 Nov 148,781 75.2%
2011 Oct 147,501 74.6%
2011 Sep 147,833 74.7%
2011 Aug 153,674 77.7%
2011 Jul 152,540 77.1%
2011 Jun 150,834 76.2%

Cblambert (talk) 17:49, 26 May 2014 (UTC)

The above table is unreadable as it appears.Constant314 (talk) 17:56, 26 May 2014 (UTC)
See above formatted with proper wikitable
I suspect lower TOC level has at least partly to do with this decline.Cblambert (talk) 03:55, 5 June 2014 (UTC)
I think the peak was caused by a lot of editing in that time frame. If 1000 editors had transformer on their watch list, it would only require an extra 100 edits during the peak month to account for the difference. It would be interesting to compare views per month to edits per month.Constant314 (talk) 04:45, 5 June 2014 (UTC)
I think it is due to both edits and 'categories' as defined in https://en.wikipedia.org/wiki/Wikipedia:Pageview_statistics. This falls under the larger question of https://en.wikipedia.org/wiki/Search_engine_optimization, which is the subject of intense research currently for marketing reasons. Intuitively, searches are a function of how deep one digs into any given class of documents. Bottom line: In my view, it pays to be careful about TOC level and there is an optimum TOC level for maximizing view statistics . . . Stay tuned. Cblambert (talk) 05:38, 5 June 2014 (UTC)
Note that per earlier Talk discussion, this article ranked 1882 on Feb 8 2013 (vs. 2304 now or minus 22% delta) in traffic on en.wikipedi a.org.Cblambert (talk) 21:32, 11 June 2014 (UTC)

Leakage flux Being essential

In the leakage flux section, the last two sentences of the first paragraph are: "Nevertheless, it is impossible to eliminate all leakage flux because it plays an essential part in the operation of the transformer. The combined effect of the leakage flux and the electric field around the windings is what transfers energy from the primary to the secondary." While probably true, this assertion needs to be explained or removed. And I say removed because it is a teaser or even intellectual snobbery. The sentence might as well say “there is something interesting and profound about the leakage inductance, but it is too difficult to explain.”

The reference is POWER FLOW IN TRANSFORMERS VIA THE POYNTING VECTOR by Edwards and Saha which appears to have been published in the Proceedings of the Australasian Universities Power Engineering in 2000. Unfortunately, it is a primary reference. And the link is broken.Constant314 (talk) 21:08, 1 June 2014 (UTC)

Done as suggested above.Cblambert (talk) 18:01, 17 June 2014 (UTC)

Ideal Transformer getting too complicated.

I think the ideal transformer section is getting too complicated. I think it should be confined to the effect that the transformer has on the circuit that it is in. For that we only need the two-port equations:

• Vs = a Vp
• Is = Ip /a
• We can say that the ideal transformer is lossless without deriving it.
• We can define “a” as the turns ratio without justifying it.

From that we can discuss how the ideal transformer decreases losses in electric power distribution. We can discuss how it performs impedance matching and give an example which shows more power to the load. We can discuss why a transformer is often used in power supplies to convert the mains voltage to a safer voltage. We can discuss voltage transformers and current transformers used as instrumentation. I think discussion of all internal structure should be elsewhere, except for defining “a” as the turns ratio. The internal structure stuff about flux and linkage and infinite inductance and zero leakage inductance could be:

• Put it in a newly created Ideal transformer page. I like this because we can go at more than one way.
• Put it in a “Hidden” structure.
• Incorporated into material further down the page.

Constant314 (talk) 21:35, 13 June 2014 (UTC)

I don't agree. Why this sudden change of heart? What motivate this radical dumbing-down? I don't understand this flight away from "internal structure" (?) stuff (?!). I don't understand any of it. Cblambert (talk) 23:14, 13 June 2014 (UTC)
In this vein, I refer Constant314 to the following Talk comment from Steinmetz equivalent circuit
"Well I, for one, am delighted with the content about the equivalent circuit, and am endebted to the authors for the name Steinmetz equivalent circuit. This is the sort of 'assumed knowledge' within the industry that is actually extremely difficult to find simply described, and even more difficult to find sources for. This whole section has saved me hours and hours of work today. And I find the algebra enlightening.--Robert EA Harvey (talk) 22:43, 16 April 2014 (UTC)
First content below lede needs to address basic principles, the usual way to do this being to start with ideal transformer.
==Ideal transformer== is very old content which has been enhanced over the years to reflect current status.
Bottom line: The Transformer article has to hang together as a cohesive whole along deliberate scientific method lines starting with of course basic principles. It is not enough to capriciously say ideal transformer section is 'too complicated' because ideal transformer is interrelated to induction law, real transformer, history and other sections . . .Cblambert (talk) 03:33, 14 June 2014 (UTC)
I assure you that if I ever make a capricious comment that I will include a :) . But, let me be clear. I think that for the ideal transformer section, the target audience are high school graduates who know ohm’s law and that volts x amps is power but do not know the meaning of inductance, flux or derivative. In accordance with write one level down, the section should be written for high school students who are taking or have taken high school physics.Constant314 (talk) 17:59, 14 June 2014 (UTC)
The issue here therefore appears to be about the whole transformer article not just ideal transformer section. There is no derivative in ideal transformer section. You are not seriously suggesting that there be no mention of inductance in the whole transformer article? What is connection between high school student audience and ideal transformer? I don't agree with the whole thrust of what you are suggesting on basis of the proof of the transformer article pudding being in the view statistic eating, which has been historically high. In absence of more precise enunciation of what you are suggesting, the status appears to be just fine. Having been instrumental in qualifying for GA for VFD article, I can assure that there was no artificial dumbing-down imposed on the qualification process along the line you seem to be suggesting. And, yes, the VFD article's GA process was approve with the term derivative, duly explained, of course. I think you underestimate WP's target audience however it is. Let's hear it from other Transformer article editors.Cblambert (talk) 05:12, 15 June 2014 (UTC)

You raise several points, so I will intersperse my replies within your comments.

• The issue here therefore appears to be about the whole transformer article not just ideal transformer section.
I disagree. There is no reason that every section in the article must be aimed at the same target audience.
So what is the criterion for saying one section is one audience and another section is another audience? It does not make sense that whole article is not same audience.Cblambert (talk) 21:25, 15 June 2014 (UTC)
• There is no derivative in ideal transformer section.
That is true. I use the lack of knowledge of derivative to help define the target audience for the ideal transformer section. This answer does not make sense to me.Cblambert (talk) 21:25, 15 June 2014 (UTC)


• You are not seriously suggesting that there be no mention of inductance in the whole transformer article?
Of course not. My comments applied strictly to the ideal transformer section. What gave you the idea that I was commenting about the entire article?
It does not make sense that whole article is not same audience.Cblambert (talk) 21:25, 15 June 2014 (UTC)
• What is connection between high school student audience and ideal transformer?
High school students, particularly those who expect to pursue technical training after graduation from high school are likely to know a little bit about transformers and likely to want to know more. They are unlikely to know anything about flux and permeability and they should not need to know that to make sense out of the ideal transformer section.
It does not make sense that whole article is not same audience.Cblambert (talk) 21:25, 15 June 2014 (UTC)
• I don't agree with the whole thrust of what you are suggesting on basis of the proof of the transformer article pudding being in the view statistic eating, which has been historically high.
I do not have any idea about what you are trying to say.
Ignore.Cblambert (talk) 21:25, 15 June 2014 (UTC)
• In absence of more precise enunciation of what you are suggesting, the status appears to be just fine.
I am precisely suggesting that anything internal to the ideal transformer, except turns ratio, be moved elsewhere. Note, I say moved, not removed. That would include any mention of flux, magnetic core, permeability, magnetomotive force, amp-turns, inductance and impedance. Change impedance to resistance. All those things could be easily moved to the next section.
I don't agree on basis that selective target audience for different sections is arbitrary and therefore unworkable with multiple editors involved.Cblambert (talk) 21:25, 15 June 2014 (UTC)
• Having been instrumental in qualifying for GA for VFD article, I can assure that there was no artificial dumbing-down imposed on the qualification process along the line you seem to be suggesting. And, yes, the VFD article's GA process was approve with the term derivative, duly explained, of course.
That article seems to be written at an appropriate level for the likely audience. That audience is not the same as the audience for transformer. It would be a mistake to write the entire transformer article for the same audience as VFD, although some sections might be written for such an audience.
VFD and Transformer articles should both same audience throughout.Cblambert (talk) 21:25, 15 June 2014 (UTC)
• I think you underestimate WP's target audience however it is.
WP does not have a target audience. WP has articles with a target audiences that range from elementary school to post PhD. The target audience for transformer includes high school students, especially those on the technical track. I would further characterize them as knowing algebra, ohms law, volts x current = power and conservation of energy but not knowing calculus, inductance, capacitance, flux, permeability, permittivity, impedance, Faraday’s law, Maxwell’s equations. The ideal transformer section should be written for those students.
That is your opinion. I dont' agree.Cblambert (talk) 21:25, 15 June 2014 (UTC)
I would like to know what target audience you think the ideal transformer should be written for and how you would describe that audience.
Transformer article should be viewed as a whole with one target audience in mind, the ideal transformer section building the first building block after the lede from among other basic principles sections towards a cohesive whole for the article.Cblambert (talk) 21:25, 15 June 2014 (UTC)
But who is your target audience?Constant314 (talk) 01:33, 17 June 2014 (UTC)
The transformer article's audience is the audience reflected in the 5,277 revisions by 1,697 editors in the 13 1/2+ years since article's inception by Ray G. Van de Walker on Oct 12, 2001.Cblambert (talk) 04:08, 17 June 2014 (UTC)
I invite comparison of perceived audience reflected in current article versus article snapshot from 17 Feb 2012, date of my first edit ever. (see https://en.wikipedia.org/w/index.php?title=Transformer&diff=477399779&oldid=477396879).Cblambert (talk) 05:56, 17 June 2014 (UTC)
I am not sure what you mean. Can't you just say in words who you think the audience is? Do you expect them to be a electrical engineers for example?Constant314 (talk) 20:52, 17 June 2014 (UTC)
The vast number of my edits have been re-shuffling improvements to existing content, formatting citations and references, cosmetic enhancements, and so on. So you tell me what audience these 5,277 revisions by 1,697 editors, including me, is now targeted at. Seriously, what do you think the transformer article's audience is targeted at? What do you think the current variable-frequency drive WP:Good article's audience is targeted at? WP:Make technical articles understandable suggest benchmarking similar articles a guide to judge appropriate audience. In your view, how do other such articles stack up to transformer article?Cblambert (talk) 21:30, 17 June 2014 (UTC)

I note List of physics concepts in primary and secondary education curricula include the following electricity and magnetism topics

No explicit treatment of 'inductance' but lots of implicit treatment.Cblambert (talk) 00:50, 19 June 2014 (UTC)

That is an impressive list of what a student may have been exposed to by the time he has finished high school physics. There being no third voice to create a majority, I will let it rest with the final comment that I would make it simpler, but you are the one doing it and I am not, so do it as you think it should be.Constant314 (talk) 02:02, 19 June 2014 (UTC)
WP:Verifiability prevents being much more simpler than it is now. Ideal transformer is very well documented and treatment becomes confusing if too glossed over too much. Many have tried in this article. Evidently with less than stellar results so far . . .Cblambert (talk) 07:06, 19 June 2014 (UTC)
Maybe new WP article called 'Transformer basic principles' is eventually needed.Cblambert (talk) 06:03, 19 June 2014 (UTC)
Leakage inductance would be good nucleus towards such new 'Transformer basic principles' article.Cblambert (talk) 16:25, 19 June 2014 (UTC)
• Let's hear it from other Transformer article editors.
Agreed. Constant314 (talk) 17:20, 15 June 2014 (UTC)

'Instructive alterations' pruning

Among some 18 odd edits by him on 29 Jan & 1 Feb 2014 (and evidently no edit by him since or before), User User JaunJimenez made an 'Instructive alterations' edit to the lead at 7:30 on the 29th of Jan 2014 (https://en.wikipedia.org/w/index.php?title=Transformer&diff=592925461&oldid=592923508), which included two paragraphs now included more or less intact in the History section's Invention sub-section and as the 1st par. of Applications section, and which I intend to prune radically soon. Cblambert (talk) 04:42, 19 June 2014 (UTC)

I note that User JaunJimenez has been blocked indefinitely.04:47, 19 June 2014 (UTC)Cblambert (talk)
User JaunJimenez is also suspected sock puppet of Jwratner1 -> I have today deleted following edits by Jaun Jimenez: