Is my 3-way switch economical ?

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Re: Is my 3-way switch economical ?

Yes thats what I am saying in this area upper east Tn. they did it for years.

I thought it was common practice. It changed here about five years ago now we have to use 12/3 but for years from the time I got into the electrical trade in the 60s until then it was common practice this is for residential using romex only.

I said it was optional if the local area permitted it.

I don't know how long you have been in the trade but things do change if everyone else used 14/3 I never questioned it I knew according to NEC 14 is just good for 15 amp. but believe me it was allowed at one time and probably in your area also although I don't know that for sure.

[ December 26, 2004, 09:24 AM: Message edited by: ronaldrc ]
 
Re: Is my 3-way switch economical ?

Like I said things change we use to use barb wire fence for the grounded conductor going to the barn.


Ronald :)
 
Re: Is my 3-way switch economical ?

WOW THIS IS CONFUSING LOL. The easiest way I know is power to first common, tie travelers together, second common goes to device...or am I missing the point of this post..? :confused:
 
Re: Is my 3-way switch economical ?

Oh! The question?

That evolved at the 13th post. Aelectricalman (who posted the original thread) said:
Thanks to all who have helped. There can never be enough ways to wire a 3 way. Anyone wired a 7 way before. I guess once your past a 4 way, its all cut an dry, but it was pretty cool. Anyone top that?
 
Re: Is my 3-way switch economical ?

Al, do you mean 7 switches when you say 7-way? Starting with the basic 2-switch hookup, you can insert as many 4-way switches between the 2-ways as the code allows--maybe it doesn't say.

I have made a neat diagram for explaining all this, but don't have a way to show it yet.
 
Re: Is my 3-way switch economical ?

Rattus,

Those are aelectricalman's words. 7-way is his term. He is the one who will have to speak to what that means to him.

edit typo

[ December 27, 2004, 02:42 PM: Message edited by: al hildenbrand ]
 
Re: Is my 3-way switch economical ?

I just realized something. The travelling bus threeway is in violation of 310.4, unless it's run in 1/0. :D

The common and the...whoa.

All threeways are in violation of 310.4. Never mind. :D
 
Re: Is my 3-way switch economical ?

I'm surprized this hasn't worked its way into this thread yet: Anyone ever done any double pole 3 and/or 4 ways? A three way would be easy, just use dpdt's but what would you do for a four way? Would that be a quadruple pole double throw? Wonder if my supply house has one of those....
 
Re: Is my 3-way switch economical ?

The traveling bus 3-way circuit is in Practical Electrical Wiring. I have never seen it before with 4-ways integrated into it. However, the circuit can have voltage drop problems with some of the on positions because the power has to go back and forth through the different wires.

One time I did use the traveling bus scheme for the hallway and kitchen 3-ways that were on the same circuit. I had to draw a schematic diagram for the electrical inspector. He said, "You're right. It is a legal circuit. Thanks. I will have to show this to my boss."

The one problem with this circuit is that in the off position it does parallel the conductors but there is an exception for paralleled conductors if any single conductor can carry all of the current from a heating standpoint.
 
Re: Is my 3-way switch economical ?

My question would have to be this: It is possible in this wiring configuration for both hots to energize when 4 ways are used :D
 
Re: Is my 3-way switch economical ?

Allen,

I'm not sure I caught your question (or questions).
To switch and feed from a 4 way is a simple joint to make up,but in this scenario you have 2 4 ways that are being used as switch and feed locations.Why do this ?
I think there are two parts to the answer. </font>
  • <font size="2" face="Verdana, Helvetica, sans-serif">The way the occupant wants to have the lighting switched for their "lifestyle".</font>
  • <font size="2" face="Verdana, Helvetica, sans-serif">Once one is willing to think of this circuit, a certain economy of material and labor of installation kicks in.</font>
<font size="2" face="Verdana, Helvetica, sans-serif">As for #1, imagine a single family residence with a detached garage. Three outside lights, one at the house front door, one at the house back door and one at the garage service door. Four switches, one each at the front and back house doors, one inside the garage service door and one inside the garage vehicle door.

Any one switch can turn off all the fixtures, think: a matching set of decorative exterior fixtures. I have noted a client-type over the years, a client that hates walking from location to location to turn off the lights (usually after the mate and kids) who is tickled pink at this type of ease-of-use. For low amperage load, voltage drop is not likely to be an issue unless the garage is too far away from the house.

The garage is provided unswitched hot power for receptacles. Conductor length is minimized, helping to manage voltage drop for "general lighting" load.

For #2, I like the example of a rambler house with the master bed on the far end from the electrical service. Imagine a long hallway leading past the other beds & bath, a light fixture at both ends of the hall. I can put two, three, four switches along the hall, hit the lights with short whips and carry the branch circuit along to power the master bed.
 
Re: Is my 3-way switch economical ?

Originally posted by mc5w:
...but there is an exception for paralleled conductors if any single conductor can carry all of the current from a heating standpoint.
Are you talking about 310.4 exception no 2? It doesn't apply to a switching system that directly supplies the load. Read closely. :(
 
Re: Is my 3-way switch economical ?

The most economical 3-way I ever installed was a pullchain right smack in the middle of an old existing garage. The pullchain lt. had 2 strings from the same chain(each About 20' long!) each went across the ceiling and through a couple eye hooks on each side of the garage and hung from there! You walk in one side pull the string/chain On, you walk out the other side, pull the string/chain off! Worked great! :D AND NEC compliant!!!

Note: To add a Fourway you just need more string and a couple more eye-hooks!

It was my garage!
:cool:
Dave
 
Re: Is my 3-way switch economical ?

Here is a graphic from Ronaldrc.

site1017.jpg


For those who haven't visited Ronalds web page, you should do yourself a favor and take a gander, very informative and educational.
icon14.gif


Go to Ronalds page

Roger
 
Re: Is my 3-way switch economical ?

Quite a few relay logic circuits parallel conductors when in certain states. Evidentally there has been an unofficial and unwritten exception that switching and relay schemes are allowed to parallel wires by means of the contacts. For instance, an electrically held motor controller has wires in parallel in between when the controller closes its auxiliary contact and when the start button is released. Same thing happens when 2 contacts are ORed together by wiring them in parallel and the wires could be paralleled for a substantial period of time.

If you want me to propose an official rule for these cases I can certainly post it but not tonight.

In one of the Audel electrical books there are schematic diagrams for lighting circuits that use a master control relay contact at the start of the branch so that a burglar or fire alarm can turn on all the lights. Downstream of the master control relay contact you have the always on hot wire and the MCR hot wire. You would use a 3-way switch in place of a single pole switch and it would switch between the always on wire and the MCR controlled wire. Likewise, a 3-way circuit would use a 4-way in place of the first 3-way. This is theoretically not a parallel conductor situation but you might need to have 2 master control relays with contacts in parallel if the burglar alarm and the fire alarm are required to be separate systems.

[ April 05, 2005, 03:00 AM: Message edited by: mc5w ]
 
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