Talk:Rotary phase converter

list of commercial phase converter manufacturers
The list of commercial phase converter manufacturers simply bounces back to this page. I am a newbie here and a little hesitant to edit other folks works. In addition I am not sure how to unlink the "List of commercial phase converter manufacturers" and make it its own page.

There is one commercial company still listing in this page and some of the links go to highly commercial places. I sould like to see the List of commercial phase converter manufacturers recreated as a list. --Ottojas 21:11, 9 February 2007 (UTC)


 * I agree that a list is useful. I removed the redirect and started a basic list of RPC companies alphabetically by type manufactured.  I personally think including a list of mfg links on this page (Rotary Phase Converter) is fine as long as we define it that way.  Several of these sites have really good advanced general and technical information on them, in addition to selling a product.  We can keep it as a separate page for now and maybe we will get some feedback to re-instate it here instead? --Theodore1942 10:17, 1 March 2007 (UTC)

Commercialization of article?
We seem to have a few commercial phase converter companies putting and replacing their links.

I created a page just for them: List of commercial phase converter manufacturers with the intent to have a list of commercial manufacturers without having any sorts of struggles or improprieties on the main phase converter pages.

I intend to move all commercial links to that page. Comments? --Ichudov 13:34, 20 June 2006 (UTC)


 * You know, the one link you have on the main article to "phaseconverterinfo" is owned by a commercial company. Do you think it's fair to list them?  Shouldn't they be listed as is on the commercial site?


 * Registrant:
 * Phase Technologies LLC, 1141 Rand Rd, Rapid City, SD 57702, US
 * Domain Name: PHASEPERFECT.COM


 * And... Registrant:
 * Phase Technologies LLC, 1141 Rand Rd, Rapid City, SD 57702, US
 * Domain Name: PHASECONVERTERINFO.COM


 * Seems to me that this would give an unfair advantage in the commercial sale of their product perhaps or an unfair advantage in at least the search engine linkeage? It's a link ranking tactic to gain popularity.  The more sites you have linking back to your main page the higher rank the engines will think you have.  Thing is, they don't recognize the site owners so as they have done and others...they buy similar relevant domains, throw their links all over the pages and link back to their main page.  Seems to be working for them quite well :0)


 * I would hope that wikipedia won't promote their commercial products on its pages. -- — Preceding unsigned comment added by 71.205.93.182 (talk • contribs) 01:12, September 10, 2006

A request for other folks to review this page
Would anyone please review the Rotary phase converter page. I am hesitant to do any of the changes necessary to this page without some support. As a newbie I would like advice and as a person with commercial interests in a related area I do not want to be biased or exposed to charges of bias.

The issues.

The generator claim is one also made by American Rotary, which is the commercial company you get when you click on the external link "Parts For Building a Phase Converter". It should at least be supported by some sort of reference to literature. I have never seen this claim made in a technical article. The link to "List of commercial phase converter manufacturers" which was apparently added by a generous wikipedian to give these folks a place to post, is a redirect back to the Rotary phase converter page.
 * 1. Rotary converter covers the subject in a less biased manner.  Rotary phase converter is redundant since it is simply a species of rotary converter.  Would the additional information fit better under Rotary converter?
 * 2. Rotary phase converter is full of value statements that have to do with a particular manufacturer --such as-- "The best types of RPC use actual three phase generators" a statement which would be difficult if not impossible to validate:  The best in what sense??  Horsepower/dollar??  Voltage balance at full load??  Best for my application??
 * 3. The link to "article on power factor" goes to an "organization", every page of which is an ad for "PhasePerfect", another manufacturer.
 * 4. The article is full of odd verbiage.. "The quality of three phase power generated by such a phase converter may or may not be satisfactory," and "Besides RPCs (the most popular technology used to convert phase), there are other technologies available today that may or may not perform as well as this proven technology."

The page was likely built by a rotary phase converter manufacturer as evidenced by the external links and the arguments for what is the "best" technology.

I am tempted to edit this article but am held back by the above considerations and questions. Should Rotary phase converter exist at all or just be an expansion of the Rotary converter article? There is very little real information in the article although it does contain some good links to "how to build your own" style articles.

Is anyone interested in this matter and willing to take a look at the page? I would be happy to make changes if they were vetted first. Better yet would someone else, clearly unbiased, become interested and do some of the editing. If I make changes, should I post a request here or elsewhere to get them reviewed and edited?

Thanks --Ottojas 03:15, 22 February 2007 (UTC)


 * I've had a read through and made some (minor) alterations but I have no serious criticism to make. Largely the article seems a lot better than your RfC led me to expect. To improve it further, I would suggest adding inline references (to non-commercial sources), and putting in links to other Wikipedia electrical or engineering articles. Good luck! SheffieldSteel 19:43, 7 March 2007 (UTC)

I have one serious criticism: I believe this statement is incorrect "A voltage is induced in the third terminal that is shifted by 120° from the voltage between the first two terminals. In a three-winding motor, two of the windings are acting as a motor, and the third winding is acting as a generator." In fact, two of the phases in a idler motor rotary phase convertor connect directly from the input to the output. Since these two inputs are 180° out of phase, two of the outputs MUST also be 180° out of phase. That leaves the third, synthesized phase output to be, at best, +/-90° out of phase with the other two. This is readily observed by connecting an oscilloscope to a rotary phase convertor output as I have done and recorded in this short youtube clip. Rotary phase convertor shutdown I've uploaded images of the circuit diagram and plots of the resulting output voltages which you can see are accurate as they match the results in the video clip. --Cuhlik (talk) 01:01, 17 November 2019 (UTC)

PhasePerfect and Phaseconverterinfo are the same:
Domain names: PHASEPERFECT.COM, PHASECONVERTERINFO.COM

Both have the same registrant and administrative contact:

Registrant: Make this info private
 * Phase Technologies LLC, 1141 Rand Rd, Rapid City, SD 57702, US

Administrative Contact: ruthjensen@rushmore.com
 * Phase Technologies LLC, 1141 Rand Rd, Rapid City, SD 57702, US
 * Phone: (605) 343-7934, Fax: 605-343-7943

--Ottojas 23:36, 1 March 2007 (UTC)

Removal of rotary converter links
The term rotary converter is broad in its use and can refer to any number of electrical machines. But in the classical sense it has always described the synchronous rotary converter. The synchronous converter was a device that resembled a DC dynamo but had slip rings in addition to the commutator for AC power input. It could turn AC current into DC or vice versa. It is not a motor generator set or rotary phase converter. I know it is confusing but all of my classic electrical literature refers to the synchronous rotary converter simply as a rotary converter.

I will remove all links to rotary converter and change term to rotating electrical machine where necessary. Thaddeusw (talk) 23:43, 16 July 2009 (UTC)

Three phase motors on single phase - do they or don't they?
From the article:- A three phase induction motor can be run at two-thirds of its rated horsepower on single phase power applied to any pair of legs, once spun up by some means.

But also:- Three phase motors cannot run on single phase power without a device to generate three phase power.

Needs some clarification by someone in the know! Mspritch (talk) 10:06, 23 August 2009 (UTC)


 * Three phase motors can in fact run on single phase. The problem lies in the fact that in a 3 phase motor, the 120 degree phase separation of the power wave forms create a "chasing" effect in the stator windings. This "chasing" magnetic field is what spins the rotor. But single phase has no such chasing effect.


 * To start a single phase motor a capacitor is usually used in series with a second smaller set of starter windings. The capacitor causes a change in phase angle of the two windings (primary and starter) and the rotor begins to spin. Once up to speed (less than a second) a centrifugal switch shuts the starter winding circuit off and the motor runs normally.


 * Now where does all this get us? Well a three phase motor has three (or more if its multi-voltage) windings so we need to wire them so one winding behaves like a starter winding. You wire the motor in a star (aka "Y") configuration and put 240 volts to two of the legs. The last leg has a capacitor wired in series to turn its winding into a starter winding.


 * Since a 3 phase motor does not have a centrifugal switch, a timer relay is used to start the motor (usually a second or two). Once the motor is up to speed the third leg now becomes a third phase. The magnetic field produced by the spinning rotor turns the now unconnected third winding into a third phase.


 * You then simply wire a three phase motor to the three legs of the motor and viola, it spins with no special modifications. One can be built quite cheaply with a good running junk yard 3 phase motor, capacitor and timer relay.


 * Just be sure to disconnect any load to the pahse converter before starting. You could use a contactor wired to the starting timer relay so when power is applied the load is disconnected allowing the rotor to spin up. Once the timer finishes, the load is reconnected automatically. 68.165.249.102 (talk) 18:09, 7 March 2012 (UTC)

Invention?
Do we have a source for their invention and inventor? At present it's getting added to Hungarian inventions on the basis of Kando having invented them. However Kando was primarily interested in their application to railways, as a means of using 3 phase motors with single wire catenary supplies. Did he invent the phase converter? Was this invented first, then conveniently used for railways? Or was it invented to meet this specific railway need? Andy Dingley (talk) 23:17, 13 May 2014 (UTC)

This article has lots of issues
The converter from 3 phase 50 Hz to 1 phase 16 1/3 Hz is not a phase converter. It is a motor-generator.

The motor starter is not a phase converter; it is a starter (condenzator). (The static phase converter is a special transformator). -- Robogos (talk) 13:03, 18 June 2015 (UTC)


 * Phase converters can be, and were, used for that conversion on railways, but it's not clear what Kandó was using. You're right though, this article is poor and mostly needs some decent sourcing. Andy Dingley (talk) 13:28, 18 June 2015 (UTC)


 * Kando made the (nearly) complete system is here or here


 * The short description of Kando locomotives. He was the engineer who designed the synchronous phase converter and electrical system of locomotives. At the beginning of of 20th century he and mr. Verebey recognized that the future of locomotives is the single phase 50 Hz feed system. The problem is that the syngle phase asynchronous motor haven't got any starer torque (that is why other systems used DC or "universal" motors).


 * He made the synchronous phase converter to convert single phase to 3 or more phase current (switchable). The traction motor (by original design) had a special wingding where the speed of motor was switchable, by changing the number of poles, by changing number of phases. (the modern simplified version is dahlender motor).


 * The production version the motor had used 3 independent 3 phase wingdings. It simplified the system but increased the size of traction motor -- Robogos (talk) 18:18, 18 June 2015 (UTC)

Induction motor vs induction generator?
As I understand it, induction motors spin at a speed below some multiple of the single-phase line frequency, while induction generators spin at a speed above the same multiple of the line frequency.

How is this speed difference worked out for induction phase converters so that the output of the third phase is actually usable?

-- DMahalko (talk) 19:44, 13 April 2016 (UTC)

There is a synchronous motor (single phase) and generator (3 phase) with common rotor and stator. An AC motor spins on the device to synchronous RPM. The traction motor is a 3 phase induction motor.

Robogos (talk) 14:24, 4 November 2016 (UTC)

Sorry. I missed Your question. In asynchronous phase converter, there is a 3rd windings, for 3rd phase. The magnetic field is identical, that on the other 2 windings. If the usage of phase converter is symmetric, the output voltage of phase converter will be symmetric.

Robogos (talk) 14:44, 4 November 2016 (UTC)

Phase relationship is 120 not 180
> Because two of the outputs are the same as the single phase input, their phase relationship is 180°. This leaves the synthesized phase to be +/-90° from the input terminals.

This line appears to be wrong or at least very misleading. Here is a video explaining: https://www.youtube.com/watch?v=mUXLxK_zI24 99.145.236.63 (talk) 21:41, 27 May 2023 (UTC)


 * The phases are measured between L1&L2, L2&L3, and L3&L1. Note that only one of those contains both the single phase connections. The phases between these three voltages is 360/3=120. The 180 phase you are talking about is between L1&neutral and L2&neutral. When measuring three phase phases there is no neutral. Note that the L2&L3 and L3&L1 both include the simulated leg (typically L3) and are unrelated to the L1&neutral and L2&neutral voltages you are referring to. Your not necessarily wrong, but are discussing a different way of measuring voltages and comparing phases. gdChinaCat (talk) 01:15, 14 January 2024 (UTC)

SI units
The use of ‘horsepower’ in the modern world seems rather quaint. 90.240.99.207 (talk) 17:03, 10 March 2024 (UTC)