ECN Forum Forums Code Related Discussion NEC & other Code issues 2 wire travelers, again

maybe you could use a coast 3-way system. This systems has no "travelers" only a hot, switch leg, and a common. ( Note the common is not a neutral This is a code legal 3 way system )

dfe,

What is a "coast" system, and how does it work?????



Peter

Hi Peter

A coast 3 way is just one of 3 ways to hook up a 3 way ( someone once told me that why it called a 3 way " you can hook it up 3 different ways...I don't know if this is true ). Only two of the 3 are nec approve.

the coast 3 way uses the same type of swith- spdt its just wired different

Standard system
switch "a" hot to common, travelers to t1 and t2 switch "b" switch leg to common travelers to t1 and t2
coast system
Switch "A" hot to t1 switch leg to t2, common join to common of switch "B" hot from switch "a" join to switch "b" t1 much like a traveler would, the switch leg from switch "a" follow in the same manner to switch "b" t2.

maybe it may be better to say
Join common to common
Run your hot and switch leg the way you would you travelers.
what is neat about this system is you have you hot a switch leg on both ends, and in the middle as well. lets say you have a light above each 3 way and a 50' long hallway with a few lights alone the way. with only 4 wires running from box to box you have all you need.The neutral stays white, you make the black the hot red is the switch leg blue as the common. Using the coast as you can see save the "I start my 3way here with the hot and end it there with the switch leg and pull the switch back to the other light back at the start. then I'll run the hot over to the other end for my other light switches". With the coast system you have what you need at both ends.

hope that this will help its hard to explain this with text, If you and I was at a job site this would be a simple drawing on the wall.

Found this link through the current 3-way thread.

Never though of the coast system of 3-way wiring, nice tool to have in my arsonal now

The only problem is that in the 2nd configuration the run could be 150% longer than the traditional method. Would be a bit confusing to the trouble shooter why in one position the lamp is dimmer than in the other position

Let me know if I got my diagrams wrong from your descriptions dfe, but they appear to be correct.






[This message has been edited by dmattox (edited 07-09-2005).]

Bah, UBB > me tonight

Ignore this post!

[This message has been edited by dmattox (edited 07-09-2005).]

Some of my worst nightmares have been troubleshooting weird switching circuits. Sometimes the conclusion was that the wiring was never right to begin with...there were not enough wires to do what had to be done, but no one ever really noticed until now that "With this switch down you can't make the other 2 switches that go to the hall lights work."

I appreciate knowing all these ways of doing it, but still maintain that wiring 3 and 4 way switches is not the time to show how creative you are.

So true poorboy, with how much my guys miswire normal 3-way switches, I don't think I would ever do a coast system. But, its good to know how someone might do it.

Another problem with the coast system is that you can't add a 4-way switch without redoing the whole thing. Or at least I can't figure out a way to do it.

As an EC, it's very refreshing to go on a service call where a homeowner has tried to replace a three-way or four-way switch and find the original EC used standard methods and simple color coding (travellers with matching color---a different color than the power). I can install the switch correctly without tracing the wiring.

Dave

I've had to rewire 3-ways where we used color coded travelers and some of my guys still screw it up

I found a "coast" a few years ago in Cape Coral while sorting out a 3 way replacement gone bad for a friend. I really didn't know what happened or how it ever worked until I saw this picture. I just pulled out both switches and started over with the "normal" method.