three and four way swithes

Status
Not open for further replies.

steelersman

Senior Member
Location
Lake Ridge, VA
al hildenbrand said:
I'll do you one better than travellers in a 2-wire.

Consider:

TwoWireTravellingBus3Way.jpg
All of these are ignorant in my opinion. Why can't people just use the easiest method: 14-3 between switches...it prevents all confusion unless maybe your on a commercial job and you have emt piped to the lights and switches and you're pulling THHN's. If you tried this illustration in a house it would be so GD ignorant and require more work to get it done and since you have to feed both switches this way you better make sure you do it from the same circuit to avoid a line to line short.
 

iwire

Moderator
Staff member
Location
Massachusetts
steelersman said:
All of these are ignorant in my opinion.

Your new here so I will explain it to you. We don't post like that here.

Al is far from ignorant, in fact he is very sharp.


Feel free to disagree with anyone here but make sure to disagree in a friendly and professional manor.
 

George Stolz

Moderator
Staff member
Location
Windsor, CO NEC: 2017
Occupation
Service Manager
steelersman said:
...unless maybe your on a commercial job and you have emt piped to the lights and switches and you're pulling THHN's.
The method makes a lot more sense in cabling methods than raceway methods. It would be ten times harder to come to this configuration using raceway methods, IMO.

I don't know if you noticed or not, but using the "Travelling Bus" threeway that Al has sketched out, two 14-2 cables could control porch lights with a pair of threeway switches on two seperate buildings, as well as power a receptacle in the detached building. All with four conductors.

However, I do agree with Bob about the 310.4 issue.

This switching method is mostly kicked around to keep your senses sharp, not as a recommendation to actually do it. :)
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
crossman said:
Got any diagrams where the travelers could legally be in a 2-wire?
That's easy enough. I have done several houses where I ran a lighting circuit like this:

In rooms with 3-ways, I ran the incoming supply 14-2 to the first 3-way, two 14-2's between the 3-ways, and a 14-2 out of the second 3-way to the next room.

Then I ran the lighting load's 14-2 out of whichever 3-way box I wanted, where the neutral was picked up, and supplied the other 3-way with a hot pigtail.

One 14-2 between the boxes was the hot and neutral, and the second 14-2 contained the travelers. I basically used the two 14-2's like 4-condcutor cable.
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
iwire said:
No comment on the 300.3(B) issues I brought up?
For the downstream loads supplied by the hot and neutral that has passed through the switching circuit in my sketch, assuming the wiring method continues as NM to the end of the circuit, leads to 300.3(B)(3).
iwire said:
I don't see any code section supporting the view that if paralleling simply happens by consequence that is OK. :smile:
.
IMO the 310.4 does not apply to grounding conductors or raceways, but I know the RMC would actually be both grounded and grounding.
I'm thinking about service conductors in a conduit, specifically, the length between the meter and the service disconnect. With respect to 310.4, it seems to me, 310.2(B) will rule out ferrous RMC as a "conductor", but not aluminum. An aluminum raceway will be a parallel conductor to the grounded service conductor inside it. That parallel current path "simply happens by consequence" of the design. No allowance for the conductivity of the raceway is offered when sizing the grounded service conductor.

If 310.4 makes the common - common conductor in parallel with the hot, in my sketch, a violation, then aluminum raceway between the meter and service disco is a violation when the grounded service conductor is smaller than 1/0.

I think a slightly refined definition of "parallel" (310.4) and "parallel installation" (300.3) is in order.
dicklaxt said:
my network becomes a hot, neutral, control wires (switch legs) and switches that can control anything desired
I agree that the switches are controllers (404.14). I can't find anything that ties the switched conductors (travelers, common - common, switched leg) with "control wires".
dicklaxt said:
When I speak of pipe I'm saying any RMC.
What about 300.20(B)?
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
George Stolz said:
The method makes a lot more sense in cabling methods than raceway methods. It would be ten times harder to come to this configuration using raceway methods, IMO.
I agree, for the sketch in this thread.

However, in my area (the Twin Cities), there is a lot of housing that was originally wired in flexible metal conduit from the end of World War II and into the mid '70s. A common run down a hallway would go from the first switch to light(s) and then to the end switch and continue on to feed a bed (or other room). There would be four conductors running switch to switch. It winds up being a conservative use of time as a lot of effort goes into running the old nonreduced wall flex.

I've even seen installations that had another branch circuit carried along with the 4 wire switching, making the run a classic MWBC (multiwire branch circuit).
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
LarryFine said:
Then I ran the lighting load's 14-2 out of whichever 3-way box I wanted, where the neutral was picked up, and supplied the other 3-way with a hot pigtail.
:grin:
As long as the lights are only taken out of one end, and a classic 3 way traveler setup is used, Bob & George won't jump on this. :)
 

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
steelersman said:
Why can't people just use the easiest method. . .
I consider myself lucky to work in a large metro area (~ 3.5 M) that offers wiring methods from the beginning of AC to present. My prefered work is breathing new life into old installations, so I've had to puzzle out some fanciful switching.

I have found the "the easiest method" can seem downright alien until I get into the mind of the original installer.

No offense taken.
 
D

dicklaxt

Guest
300-20b,,,,,,,,,I'll have to look it up monday.I don't have it memorized;)

dick
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
al hildenbrand said:
:grin:
As long as the lights are only taken out of one end, and a classic 3 way traveler setup is used, Bob & George won't jump on this. :)
They are, it is, and they wouldn't dare! :grin:
 

steelersman

Senior Member
Location
Lake Ridge, VA
al hildenbrand said:
I consider myself lucky to work in a large metro area (~ 3.5 M) that offers wiring methods from the beginning of AC to present. My prefered work is breathing new life into old installations, so I've had to puzzle out some fanciful switching.

I have found the "the easiest method" can seem downright alien until I get into the mind of the original installer.

No offense taken.
My apologies. I shouldn't have come off like that. I'll try to keep it cool.
 

steelersman

Senior Member
Location
Lake Ridge, VA
iwire said:
Your new here so I will explain it to you. We don't post like that here.

Al is far from ignorant, in fact he is very sharp.


Feel free to disagree with anyone here but make sure to disagree in a friendly and professional manor.
Yes he appears to be very sharp and not ignorant and I wasn't implying that he was ignorant I simply thought that the 2 wire method is impractical and more work. I'm sorry for offending you. I will make sure to not be so harsh and try to be more open minded in the future.
 

crossman

Senior Member
Location
Southeast Texas
LarryFine said:
That's easy enough. I have done several houses where I ran a lighting circuit like this....... One 14-2 between the boxes was the hot and neutral, and the second 14-2 contained the travelers. I basically used the two 14-2's like 4-condcutor cable.

Larry, thanks for the reply. When I asked the previous question, it was before Bob pointed out 300.3(B)(3). I knew there were plenty of ways to use multiple 14/2 cables for 3-ways, but I was going under the assumption that we had to comply with 300.3(B) and have all the conductors in the same cable.
 
D

dicklaxt

Guest
Hey Stickboy,,in your wiring schematic of the 3-way and 4-way in the house and barn scenario. I can see it works fine but wonder why you would do it this way rather than travelers to and from all switches and a switch leg return from the barn 3-way,thats assuming the panelboard is at the house?
dick
 

stickboy1375

Senior Member
Location
Litchfield, CT
dicklaxt said:
Hey Stickboy,,in your wiring schematic of the 3-way and 4-way in the house and barn scenario. I can see it works fine but wonder why you would do it this way rather than travelers to and from all switches and a switch leg return from the barn 3-way,thats assuming the panelboard is at the house?
dick


I cant take credit for the picture, but its a great diagram if your come across an existing setup and have existing wiring to work with. If I was doing the job from scratch, I personally would have just used X10... :grin:
 

donselectric

Senior Member
Location
nh
boy if i had to trouble shoot that i'd be swearing a lot at the original installer
why make thinks difficult. i alway thought the traveling bus thing was taboo.
just use 3 wire to each sw and be done...simple :D

jmo
 
Status
Not open for further replies.
Top