Talk:Switch: Difference between revisions
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:Wow, old message. I just created the page for [[Knife switch]], it should either be expanded, or merged into this one (probably merged), but I don't have the knowledge to do so. If anyone wants to merge and delete the KS page, feel free but be sure to correct the wikilinks (that's wat made me create the page in the first place). [[User:WLU|WLU]] 15:01, 1 June 2007 (UTC) |
:Wow, old message. I just created the page for [[Knife switch]], it should either be expanded, or merged into this one (probably merged), but I don't have the knowledge to do so. If anyone wants to merge and delete the KS page, feel free but be sure to correct the wikilinks (that's wat made me create the page in the first place). [[User:WLU|WLU]] 15:01, 1 June 2007 (UTC) |
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== Naming of Toggle Switch == |
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Looking at the hefty 'toggle switches' depicted here, confirms my belief that the name originated from the (fastening) toggle-like external lever. However the article attributes the name to the mechanism ... is there any evidence for the stated name origin ? Or even my suggested origin ? [[Special:Contributions/217.24.204.11|217.24.204.11]] ([[User talk:217.24.204.11|talk]]) 15:00, 11 December 2013 (UTC) |
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== Change suggestions == |
== Change suggestions == |
Revision as of 15:00, 11 December 2013
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ratings etc
it might be useful to extend the discussion to other significant aspects of switches such as voltage and current ratings, design life, environmental requirements, etc.
- And we could use photos of switches. A knife switch would be a good introductory picture. A mercury bulb switch would be an unusual twist, a common wall switch (though styles differ around the world) would also be meaningful. Perhaps someone can come up with a picture of a big electric company switch. On the other side of the spectrum, we have micro switches for all sorts of mundane tasks like determining if there's paper in the paper tray. -- Ke4roh 12:16, 18 May 2004 (UTC)
network switches?
It seems that we don't have anything to do with network switches. If we already have it, then we need a link to it on this page. --huwr
- I also overlooked it the first time. The link is in the second sentence. -- Ke4roh 12:16, 18 May 2004 (UTC)
- I've now created a full disambiguation page, so hopefully the other meanings are more prominent. - IMSoP 06:23, 27 Jun 2004 (UTC)
underwater cameras and reed switches
Is it true that underwater cameras use reed switches ? -- DavidCary 17:19, 26 Jun 2004 (UTC)
schematic symbols
it would be great to include the schematic symbols to illustrate the various configurations too. --Hooperbloob 05:14, 10 Nov 2004 (UTC)
feel free to comment on my edits (plugwash)
i've tried to deamericanise the page and also added a load of info on names of switch types and a section on multiway switching what do you guys think? Plugwash 16:11, 1 Dec 2004 (UTC)
- Well, apart from a few style issues (e.g. please capitalise the first letter of sentences), which I've fixed easily enough, I think your additions on multi-way switching are a little hard to understand. I'll have a go at improving the diagrams once I've got a decent image editor installed (if no-one else gets there first), but I think the explanation could do with "tightening up" too. I'll have a go, unless I get distracted; I might also draw some schematics for the different configurations, as this should make things much easier to understand. Nonetheless, you have solved an enduring mystery for me, which is how you can have a set of 3 switches all able to toggle the same light; up till now, I'd only figured out a way that required a transistor, which seemed a bit unlikely for my parents' Edwardian house... so thanks for that! - IMSoP 18:47, 1 Dec 2004 (UTC)
I notice you changed my table to the wiki pipe syntax is there a formally expressed preference anywhere for which syntax to use? As for the diagrams they were drawn in mspaint and im not too skilled at drawing i think the diagrams get the points accross though. Plugwash 20:20, 1 Dec 2004 (UTC)
- Um, no, as far as I know, there isn't an official guideline on which table syntax to use; to be honest, I just changed it over for the selfish reason that I find the pipe syntax easier to read (in many cases, a lot easier to read), and I wanted to fix up some other things in the table (grammar and formatting type stuff). Besides, that pseudo-broken-HTML-syntax variant you used is just plain weird! (Not your fault, I know, it's on the help page; still weird, though). So, basically, my apologies if you disagree with my preference/opinion.
- As for the diagrams - no offence, but the fact that they're done in Paint, and not even done well in Paint, shows. [Tip: even in MSPaint, you can hold down shift to constrain the straight line tool to 45° angles...] Sure, they get the points across (or the first image does; the second one is a little confusing, and I had to sketch my own diagrams to make sense of it), but they don't exactly look "professional" - if you saw those in Encarta, you'd laugh. Like I say, please don't take offence, and thanks for having a crack, but if no-one else does, I will try and draw some slightly neater versions, and hopefully make them look a little more like standard wiring diagrams, too. - IMSoP 00:11, 2 Dec 2004 (UTC)
[Random User Comment of Thanks: I am 57 and this is the first time I understand how the light on the stairs can be turned off by two switches, which I have been wondering about since I was a teenager in my parents' NJ house. Thanks! Pete] —Preceding unsigned comment added by 24.164.128.251 (talk) 14:01, 12 September 2007 (UTC)
Why UP for ON in the USA and DOWN for ON in the UK?
This is one of those bits of trivia for which I really would like to know the answer: In Britain you flick the switch down for "on" but in America you do the reverse - you flick it up for "on". I have asked no end of authoritative bods about this and no one seems to have a historical answer to explain how and why this came to be. Does anyone here know the answer? MPLX/MH 05:35, 11 Jan 2005 (UTC)
- Dunno. But I can tell you that in Europe it is usually as in the UK. Except when it isn't (my flat in Valencia seemed to have all wiring installed at random). Chamaeleon 12:43, 11 Jan 2005 (UTC)
- Don't know the answer, but (and I speak as a Brit) the American way seems better... the switch is far more likely to be knocked downwards (e.g. by something falling) and it seems sensible to switch OFF in that case. It is also worth noting that a lot of industrial switchgear (DIN rail circuit breakers spring to mind) in the UK normally switches off in the DOWN position. --Ali@gwc.org.uk 14:29, 11 Jan 2005 (UTC)
- I was born in England and then moved to the USA, but no matter who I ask, no one seems to know the answer. My guess is that it has something to do with cars driving on different sides of the street in the UK and USA; a modified spelling and pronunciation of the English language in the USA and even different measures for clothes, water and so on. Since the development of commercial electricity flowed from the USA to the UK like the telephone system, my guess is that the UK modified the US system. But the question is: who and why (apart from just wanting to be different, or plain bloody minded.)? MPLX/MH 16:48, 11 Jan 2005 (UTC)
- i would argue that at least with lightswitches accidental switch-on is less likely to cause problems than accidental switch off (the last thing you want when things are going wrong is to suddently get plunged into darkness as well. Plugwash 17:38, 2 May 2005 (UTC)
- I was born in England and then moved to the USA, but no matter who I ask, no one seems to know the answer. My guess is that it has something to do with cars driving on different sides of the street in the UK and USA; a modified spelling and pronunciation of the English language in the USA and even different measures for clothes, water and so on. Since the development of commercial electricity flowed from the USA to the UK like the telephone system, my guess is that the UK modified the US system. But the question is: who and why (apart from just wanting to be different, or plain bloody minded.)? MPLX/MH 16:48, 11 Jan 2005 (UTC)
The reason why in America it is the reverse of how it is done in Britain, is the same reason as why we drive on the left side of the road in the U.S., and not on the right, it is because after going to war against Britain, and winning their independence, the founding fathers did not want to do things like their former oppressors, so everything they would do here would be the opposite of how Britain did it. And well society doesnt easily break with tradition, so since it is done one way in Britain, In tue U.S. it is going to be done the exact opposite —Preceding unsigned comment added by 72.134.7.131 (talk • contribs) 09:11, 12 November 2006
- Whatever the reason for it, this difference really ought to be discussed in the article somewhere. Perhaps there could be a section on national standards? --SteveMcCluskey 20:01, 6 September 2007 (UTC)
- Except the War of Currents post-dated the American Revolutionary War by a century (and even then not every house had switches, etc.). That's a long time to "hold a grudge". Driving on the left or right#History also contradicts the "hold a grudge" theory by sound, practical reason: "The wagons had no driver’s seat, so the driver sat on the left rear horse and held his whip in his right hand. Seated on the left, the driver naturally preferred that other wagons overtake him on the left so that he could be sure to keep clear of the wheels of oncoming wagons. He did that by driving on the right side of the road." The Great American Grudge (TM :) also doesn't fully explain why the bulk of the countries drive on the right.
- To throw in my one two cents, I'd guess it's just natural change instead of some form of grudge. If you borrow from speciation, then two divided cultures need not maintain the same cultural customs and habits. Heck, in the US it's common to have the ground pin down in electrical outlets but I've seen it the opposite way in plenty of places. Regions just acquire their own customs. Cburnett 20:28, 6 September 2007 (UTC)
- I have imagined that the American convention imitated the likely practice with knife switches, using gravity to insure that an "off" switch with a less than tight pivot would not close itself. However, this only raises the question of why Europeans did not take the same path. —Preceding unsigned comment added by 63.86.92.198 (talk) 17:55, 8 September 2008 (UTC)
- It's an interesting observation. Though probably not true, it is quite surprising how many examples of US technology are different to British (or European). Besides the already mentioned switch orientation and the side of the road we drive on, the blades on European helicopters rotate clockwise (viewed from above) whereas US rotate anti-clockwise. Even fairground rides rotate in opposite directions (Europe: c/w - US ac/w). Standard mains frequency and voltage are different (UK: 440/240V 50Hz - US: 208/120V 60Hz). I don't believe the founding fathers came into it as much of this was not around when they committed their treasonous acts. It is more probably that as technology was independently developed on both sides of the Atlantic, differences inevitably arose. DieSwartzPunkt (talk) 17:54, 17 July 2012 (UTC)
- I can't answer this question either, but at least the default direction of rotation (even in applications where there is no direct technical reason for it) is probably down either to the traffic direction or the way screws are turned (where it would even have a technical reason). People are accostumed to a particular direction, therefore they "naturally" apply it to related applications as well. And at a later stage, standards even enforce a particular direction for reasons of consistency. But I'll add another question: Why are mains switches sometimes found on the right and sometimes on the left side of a product? (On stereo equipment the switches are mostly on the left side, whereas on computer equipment they are mostly on the right side). ;-) --Matthiaspaul (talk) 22:06, 5 August 2012 (UTC)
... And the Answer Is
I think it pretty straightforward -- the "low energy" output of the switch corresponds with the "low physical" position of the toggle. High voltage = on = up. Fairly intuitive, no? Ergonomic principle. Here's a British switch where the "on" position is clearly "over" the off position http://uk.farnell.com/siemens/3sb31018bc21/pushbutton-actuator-on-off/dp/4323350. —Preceding unsigned comment added by Feldercarb (talk • contribs) 23:23, 5 October 2010 (UTC) I will quote from "Fitting the Task to the Man" 4th edition by Etienne Grandjean ISBN 0-85066-380-6 page 140: "... to switch to 'off' it is instictive to pull the lever towards the body or move it to the left, or downwards." Feldercarb (talk) 13:35, 14 April 2012 (UTC)
The NEC mandates which way a light switch is oriented, although it doesn't explain "why"
A terminal block in the backbox
Please explain a terminal block and backbox and explain how cable is saved. You seem to need three cables between the boxes in both cases, in addition to the circuit from one box through the light and the power supply back to that box.--Patrick 20:43, Jan 24, 2005 (UTC)
- not sure how to put this.
- terminal block is this stuff http://www.tlc-direct.co.uk/Products/TLCON5.html (i belive americans use wirenuts instead) a backbox is simply the box your switch is mounted in.
- as for cable saving it depends on which switches the live and switched lives arrive at perhaps the follwoing diagram will better explain what i mean (i drew this feel free to use it how the hell you like). its uk color code so possiblly not so approprite for an article here (i deliberately kept the diagrams on the switch page free of cable color codes to avoid confusion)
- i think it needs to be said (but im not sure how best to say it) that there are many wiring LAYOUTS for two way switching but electrically they are all one of the cuircuits that i currently show on the switch page.
I have written out the wiring needed. It seems the second method always needs more. I wonder if it has any advantage.--Patrick 08:56, Jan 25, 2005 (UTC)
- the MAIN reason for using the second method is to avoid the need to use a terminal block (wirenut in the usa) in the backbox of the first switch when live and switched live arrive at the same box. http://www.mywatergarden.com/diy/2way-switching.gif shows such a configuration.
- http://www.umist.ac.uk/personal/student/Peter.Green/lamps.png is another more unusual case where the second method shown wins.
- i see you also added a link to Three-way circuit which shows a HUGE degree of national bias, is written in far too much of a howto style and specifies FAR too much locally variable detail (such as cable size). Plugwash 11:47, 25 Jan 2005 (UTC)
I did not add it because it is so useful, related articles should always be linked. Feel free to edit it; maybe we should even change it into a redirect.--Patrick 14:07, Jan 25, 2005 (UTC)
Three-way circuit redirected here
i have redirected Three-way circuit to here. The old content there was a very us centric howto. If you wish to move that content to a more appropriate place feel free to get it from the history and add an external or sisterproject link to its new home from here. Plugwash 17:34, 2 May 2005 (UTC)
Switch bounce
This page could use a section on switch bounce— Preceding unsigned comment added by 128.112.84.15 (talk) 14:44, 12 August 2005
- Multivibrator linked to Contact bounce, which does not exist. Perhaps there should be a separate page for contact/switch bounce? For now I have changed the link to the subsection within this page, since the information is here.W 13:35, 25 January 2007 (UTC)
Table column ordering
I would suggest that the first two columns of the table listing the various switch types be swapped since abbreviations are generally introduced after the concept is described. This would also make the titles easier to grok going from the unwieldy "Electronics Abbreviation | Expansion of abbreviation" to just "Type | abbreviation" --
Hooperbloob 19:53, 2 October 2005 (UTC)
switching not to be merged with switch
I do not think the switching article should be merged with switch. In my opinion, the former should cover the different ways of breaking a current (in air, oil, SF6, vacuum) and so on, together with the difficulties in swithing inductive currents, small capacitive ones....These are differente topics.
- I would agree, the issues involved would make the current article grow considerably larger than it is already.--Hooperbloob 16:54, 22 January 2006 (UTC)
- What happened? At the moment, switching is a mere disambiguation page, mentioning "For electrical switching in general, see switch". Was there ever information on the difficulties of switching inductive currents, etc. in the "switching" article, and if so, where did that information go? --68.0.124.33 (talk) 01:52, 27 January 2011 (UTC)
Knife Switch
Shouldn't this be here too? Found this text online: The "knife switch" (rarely seen nowadays) is the type that most easily demonstrates the functioning of a switch. Old sci-fi movies ("Frankenstein (1931)" or "Young Frankenstein (1974)" , for example), made extensive use of these switches in the laboratory scenes. Today, use of knife switches has been confined to 1) heavy-duty industrial applications and 2) demonstration purposes - science projects for example. The knife switch has a metal lever, insulated at the 'free end' that comes into contact with a metal 'slot'. Since the electrical connections are exposed, knife switches are never seen in household wiring. Wadsworth 22:38, 20 April 2006 (UTC)
- Wow, old message. I just created the page for Knife switch, it should either be expanded, or merged into this one (probably merged), but I don't have the knowledge to do so. If anyone wants to merge and delete the KS page, feel free but be sure to correct the wikilinks (that's wat made me create the page in the first place). WLU 15:01, 1 June 2007 (UTC)
Naming of Toggle Switch
Looking at the hefty 'toggle switches' depicted here, confirms my belief that the name originated from the (fastening) toggle-like external lever. However the article attributes the name to the mechanism ... is there any evidence for the stated name origin ? Or even my suggested origin ? 217.24.204.11 (talk) 15:00, 11 December 2013 (UTC)
Change suggestions
A handful of comments, not meant to be snarky, I just don't have time to go in and edit:
It seems to me that a the page is relatively heavy on AC uses; more info on switching in DC - even TTL/CMOS - would be useful. (I work with PICs and the like and so was pleased to see debouncing mentioned, but this could be beefed up).
Also, Wikipedia's main page on "switch" contains no information about DPST vs DPDT, etc? Seems like a glaring omission to me. Momentary vs. non, number of switchable inputs/outputs, etc., should all be a part of this page. Consider how many students use Wikipedia as their first (but hopefully not last!) research stop online.
Spincycle 14:03, 17 September 2007 (UTC)
- I agree that this article is heavy on AC. My suggestions for changes:
- Move contact bounce to its own article (it's deserves mentioning but too much about it is in this article)
- Add detail on DC switches (you can't swap a 12VAC switch for a 12VDC switch)
- Do more then mentions special types in a list. Each should have at least a couple sentences and a picture in switch.
- Electronically controlled switches: solenoids & relays, transistors, etc.
- I'd call a jog dials and rotary encoders switches too
- Rotary switches (kind of a predecessor to the jog dial)
- I'd go so far to say to split out everything electrical power related into its own article (perhaps electrical power switch) as it dominates this generic switch article which could also discussion thyristors and the like
- Momentary switches don't get much coverage
- The lead picture is nice but I think each switch should get its own picture with more detail so that it can be used where it is discussed
- Cburnett 15:20, 17 September 2007 (UTC)
- I agree that the other kinds of switches used by engineers and electronics technicians are played down. Most readers, however, encounter switches in AC household wiring. My suggestion, therefore, would be the reverse: briefly discuss the more specialized kinds of switches mentioned above, and provide links to main articles discussing them.
- BTW, you can generally swap a 12VAC mechanical switch for a 12VDC switch -- unless you're switching a big inductive load. --SteveMcCluskey (talk) 16:01, 21 November 2007 (UTC)
- I would guess that the vast majority of switches are Membrane switch. Quite a few people in the world may have seen only these. Cultural bias. 24.66.190.44 (talk) 18:30, 5 May 2010 (UTC)
Mistake in diagrams
There is a mistake in diagrams "3-way switches position 2.svg" and "3-way switches position 4.svg". These both show the neutral line as red, indicating presumably that it's live. But of course it's not. I don't know how to edit pictures so I can't fix this. Occultations (talk) 23:16, 27 April 2008 (UTC)
Abbreviations
The article has a number of undefined abbreviations that may be unfamiliar to a general audience.
- NEC
- CEC
There may be other abbreviations that also need to be examined. -- B.D.Mills (T, C) 04:25, 31 July 2008 (UTC)
- I have corrected this. NEC = National Electrical Code (USA), CEC = Canadian Electrical Code. As far as I can tell, all other abbreviations are explained. Biscuittin (talk) 12:59, 31 July 2008 (UTC)
- Thank you for your corrections. -- B.D.Mills (T, C) 12:24, 3 August 2008 (UTC)
Possible vandalism in "Others"
Are there really such things as a Mindy switch and a Jamie switch? Biscuittin (talk) 13:10, 31 July 2008 (UTC)
- I agree this is spam, and will remove accordingly. Jamie Switch appears to be nothing more than the name of an actor. Could find no such thing as a mindy switch either. —Preceding unsigned comment added by 65.0.193.228 (talk) 09:11, 7 November 2008 (UTC)
History
When were electrical switches invented? -- Beland (talk) 22:18, 2 October 2008 (UTC)
- Somewhere around Y2k, as part of researching the history of telegraphy and early electrical communication, I did an extensive Web search using all available search engines in a quest to identify the inventor of the first electrical switch. No luck. There's a lot more information on the Web now and the information might now be available. But I had a strong sniff that interruption of an electrical current to end a physical shock may have been so intuitive that this bit of history may never have been recorded. I'd still like to know. :-) Marbux (talk) 05:21, 17 July 2012 (UTC)
- Somewhere around Y2K?? And there was me using them for most of the 20th century not realising they hadn't been invented. DieSwartzPunkt (talk) 18:03, 17 July 2012 (UTC)
- Not relevant? So you think the switch was invented circa 2000. So not only do you not know how switches are rated, you don't know when they were invented either. DieSwartzPunkt (talk) 17:36, 18 July 2012 (UTC)
- I Googled for about 2 seconds and found, "1884 by a man named John Holme". Someone may be able to find a good reference of this. -- JTsams (talk) 20:27, 5 August 2013 (UTC)
- It was long before that. Joseph Henry invented the relay in 1836 1 so the switch must have been around before that. You can see an early form of switch in this picture of Sturgeon's first electromagnet in 1823, consisting of a metal arm (d) that dipped into a cup of mercury from which the wire to the electromagnet emerges. These "mercury cup" contacts are visible in other pictures of early devices. A "current reverser" switch is visible in this picture of a Henry electromagnet from the 1830s. Volta invented the voltaic pile, the first source of DC current, and showed that current could be conducted by wires in 1800 2. Before that there were just electrostatic sources, so there wouldn't have been much need of a switch. The toggle light switch was invented in 1916 3 by William J. Newton and Morris Goldberg. Cheers --ChetvornoTALK 21:36, 5 August 2013 (UTC)
- Now that I think about it you're right. The switch must have been invented with the first voltage source, a switch is nothing more than a mechanism for bringing two conductors into contact to allow for the flow of electrons. I'd say the voltaic pile or Ben Franklin is probably the era of the first switch... at least as far as North American history is concerned. -- JTsams (talk) 21:53, 6 August 2013 (UTC)
- Franklin just experimented with static electricity, which doesn't flow continuously so probably didn't require switches. I'd guess between 1800 when the first experiments with "galvanic" (DC) electricity from the voltaic pile created a need for a switch, and the 1820s when switch mechanisms appear in pictures of electromechanical devices. --ChetvornoTALK 02:49, 7 August 2013 (UTC)
- Now that I think about it you're right. The switch must have been invented with the first voltage source, a switch is nothing more than a mechanism for bringing two conductors into contact to allow for the flow of electrons. I'd say the voltaic pile or Ben Franklin is probably the era of the first switch... at least as far as North American history is concerned. -- JTsams (talk) 21:53, 6 August 2013 (UTC)
Inductive loads
"When a strongly inductive load such as an electric motor is switched on, an input surge current exists that may be several times larger than the steady-state current. When switched off, the current cannot drop instantaneously to zero; a spark will jump across the opening contacts." The high current that most types of motors draw when switched on has nothing to do with its inductance. Rather it is due to the lack of back-EMF from the stopped motor. Whatever inductance exists actually retards the rise of current for a short time. I propose to edit out all mention of motor starting, which is in any case irrelevant to the matter of arcing when the motor is switched off. —Preceding unsigned comment added by 63.86.92.198 (talk) 19:44, 20 August 2009 (UTC)
Notes
expert needed. Manually-operated and electrically-operated switches. Limit switches. "Microswitch". Signal, control and power switches. Switch enclosures. Ratings. Actuators - push button, toggle, selector, whisker, lever arm. Pressure switches. float switches. flow switches. temperature switches. AC and DC ratings, physics of contact break. High voltage issues. High current issues. Light switches. History. Reed switch. explosion proof switches. contact wetting phenomena. Industrial, commercial, household wiring applications. Mercury switches and the environment (car bodies, noiseless wall switches). One minute's free-association on the topic shows there's a lot more to be added. --Wtshymanski (talk) 18:20, 19 September 2009 (UTC)
The contact-bounce section needed work; but I think you removed both too little and too much: The introduction to the specific methods needs have the category list removed, including "hysteresis", which no longer has a paragraph at all, with the individual methods that remain simply given without trying to fit them into categories. On the other hand, the method with the latch should be reinstated and the fact that it would most likely be done with an SPDT switch made clear. This is an important technique.
- It's useful to sign your contributions with four tildes. the details of contact debouncing I think properly belong in a discussion of digital logic design, not so much in a general discussion of switches. Methods vary depending on the targeted system, whereas the origins of the problem come from the electromechanical nature of the switch. --Wtshymanski (talk) 03:20, 22 September 2009 (UTC)
The debouncing section has described a number of complicated and expensive debouncing techniques; but I have been unable to get it to at least acknowledge two of the simplest and most effective ones:
o Simply sampling at intervals longer than the longest bounce time will effectively debounce the switch. If the bounces occur between two samples, they will not be seen. Otherwise, if one sample is taken during the bouncing, it will produce either a 1 or a 0. Either way, that sample will agree with either the sample before it or the sample after it, producing only one transition. This technique may be implemented in software, by programming the sample interval, or in hardware, by passing the signal through a flip-flop clocked at the appropriate sample rate.
o When an SPDT switch can be used, it can be wired to drive one or the other inputs of a set-reset latch, which can be constructed, for example, from two simple two-input nand gates, each connected with its output to one of the other gate's inputs. The common of the switch is grounded/earthed, while its other two terminals drive the remaining gate inputs and are pulled up to the supply rail by resistors. Any bouncing as the first contact opens has no effect on the latch, while the first closure of the second contact changes the latch's state. Further bouncing of the second contact has no further effect. Similar results can be arranged with nor gates. with the set-reset inputs of more complex flip-flops if convenient, and in software, by treating the two switch contacts as separate discrete inputs:
bool switchon = switchon ? !offcontactclosed : oncontactclosed;
Bob Nelson —Preceding unsigned comment added by 75.54.95.229 (talk) 20:23, 12 December 2009 (UTC)
Single Side Stable, Latching
Now that a lot of relays are latching, traditional ordinary (non-latching, non-rotary, non-centering) relays are sometimes described as 'single side stable' —Preceding unsigned comment added by 203.206.162.148 (talk) 05:26, 11 March 2010 (UTC)
IEC 60617 symbols?
Looking at those 60617 symbols I don't see where the wires connect. I've seen a large number of European electrical drawings ranging from steel mills to hydro plants to VW cars, and I have never seen these "flag" symbols used in a schematic. Unluckily our office doesn't have access to this IEC standard, but I don't think these are meant for use in electrical schematics. Perhaps they are meant for architectural layout drawings, that is, to show where a light switch would be in a room; not for use in a schematic diagram. Can anyone authenticate the use of these symbols? They look very wrong. --Wtshymanski (talk) 14:03, 18 May 2010 (UTC)
- I've pulled them all. Some of them were described as "circuit breaker" symbols, again, though, I've never seen them. This file [1] , among others, convinces me that these "flagged" circles were not IEC 60617 switch symbols. --Wtshymanski (talk) 14:17, 18 May 2010 (UTC)
Redirect to disambiguation and rename?
- The following discussion is an archived discussion of the proposal. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.
No consensus to move. Vegaswikian (talk) 20:06, 13 December 2011 (UTC)
Switch → Switch (Electronics) – There are an awful lot of potential things that "switch" could be other than electrical switches, and I don't see why electrical switches should have a full hold on the general term "switch" when many other items in that list also go by the general term switch (I came here for network switches). Considering that (I counted 36 "may means") I think it might be more helpful to users to have Switch redirect to Switch (disambiguation) and have this article renamed "Electrical switch". I won't act without consensus, though. What do you think? TheOwlWBU (talk) 16:39, 6 December 2011 (UTC)
- Oppose - this has got to be the most common use, and the railfans aren't seriously inconvenienced by it. --Wtshymanski (talk) 18:44, 6 December 2011 (UTC)
- Retort: I agree that it is probably the most common use in real life (what with the relative popularity of lights over railroads and the OSI model), but that shouldn't mean that it should have the convenience monopoly on what is, to be fair, a very vague term! If the disambig is not changed itself to obscure the part which reads "A switch is an electrical component which can break an electrical circuit, interrupting the current or diverting it from one conductor to another. Switch may also mean...", it means that people looking for one of the other 36 forms of switches would be less inconvenienced - which they are, seriously or not - and people actually looking for electrical switches can see their goal at the top of the disambiguation. TheOwlWBU (talk) 12:19, 7 December 2011 (UTC)
- Opose: all other switches are either pretty evident and don't deserve article, or just less common. Surely, most people come here for this switch. The article contains a hatnote with the link to DAB, so everyone can find the right target anyway. — Dmitrij D. Czarkoff (talk) 16:13, 11 December 2011 (UTC)
- The above discussion is preserved as an archive of the proposal. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.
SPDT - SP3T confusion
Where in the main page it says Similar to SPDT. Some suppliers use SPCO/SPTT for switches with a stable off position in the centre and SPDT for those without.[citation needed] In common practice, just check any vendor, a switch of this kind is liste as a *PDT, P.E. SPDT, or DPDT, and in no other way. If there is a stable central position its indicated in a note or an ON-OFF-ON switch function is indicated. — Preceding unsigned comment added by Omblauman (talk • contribs) 03:37, 12 April 2012 (UTC)
2 stage switches/pressure switches
I had a look though the article and didn't see any mention of 2 stage switches like those in a camera or some torches neither did I see the kind of switch like the buttons on the gamepads of the playstation 2 or 3 has.Pleasetry (talk) 03:00, 9 July 2012 (UTC)
Sewing machine
A sewing machine pedal is a poor example of a switch, since any modern sewing machine has variable speed control so the pedal is anything but a mere switch, yeah? 217.13.7.24 (talk) 14:47, 28 September 2012 (UTC)
Rotary switch, with rotary ratcheting solenoid to change position
Does anyone know where I might find a free / CC-by / public domain image of this device, so it can be included here?
History: Motorized rotary switch, rotary solenoid, LEDEX
http://forum.allaboutcircuits.com/showthread.php?t=74358
DMahalko (talk) 05:51, 30 September 2012 (UTC)
Merge proposal from wetting current
- The following is a closed discussion of the proposal. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.
The result of the proposal was not to merge.
It is proposed that the article Whetting current be merged into this article as it already contains a (brief) section under the US spelling of 'wetting current'. This proposal is a result of a lengthy discussion on the source article's talk page — Preceding unsigned comment added by 86.159.159.194 (talk) 14:13, 18 November 2012 (UTC)
- Keep, no merge. Wetting current is its own topic with its own specific concerns. Not all instances of wetting current are on switches; it is a concern in making and breaking live connections. Binksternet (talk) 16:16, 20 November 2012 (UTC)
- Oppose. The result of the long discussion at Talk:Wetting current was to merge/move Whetting current into Wetting current. I oppose merging this into the switch article since switches are only one of several rather diverse applications of wetting currents, which could not reasonably be discussed in the switch article. For more details see the old discussion at Talk:Wetting current. Given that we have discussed the pros and cons at length already, I don't think we need yet another discussion regarding this. --Matthiaspaul (talk) 22:04, 28 November 2012 (UTC)
- The above discussion is preserved as an archive of the proposal. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.