Talk:Switch

From Wikipedia, the free encyclopedia

WikiProject on Electronics This article is part of WikiProject Electronics, an attempt to provide a standard approach to writing articles about electronics on Wikipedia. If you would like to participate, you can choose to edit the article attached to this page, or visit the project page, where you can join the project and see a list of open tasks.
B This article has been rated as B-Class on the quality scale.
Top This article has been rated as Top-importance on the importance scale.

Contents

[edit] 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)

[edit] 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)

[edit] underwater cameras and reed switches

Is it true that underwater cameras use reed switches ? -- DavidCary 17:19, 26 Jun 2004 (UTC)

[edit] schematic symbols

it would be great to include the schematic symbols to illustrate the various configurations too. --Hooperbloob 05:14, 10 Nov 2004 (UTC)

[edit] 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)

[edit] 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)

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)

[edit] 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)
Image:Old2way.png
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)

[edit] 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)

[edit] 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)

[edit] 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)


[edit] 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.

xareu_bs

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)

[edit] 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)

[edit] 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)

[edit] 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)