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From: jad@dayton.UUCP (J. Deters)
Newsgroups: sci.electronics
Subject: Re: X-10 switches used in 4-way circuit
Summary: Use at one end only...
Keywords: X-10
Message-ID: <7683@dayton.UUCP>
Date: 9 Feb 91 05:27:42 GMT
References: <463@sunpix.East.Sun.COM> <7523@exodus.Eng.Sun.COM>
Reply-To: jad@dayton.DHDSC.MN.ORG (J. Deters)
Organization: Department Store Division of DHC
Lines: 54

>In article <463@sunpix.East.Sun.COM> cram@sunpix.east.sun.com (Marc W. Howard) writes:
>->	Is there a way to use the X-10 three way switch in a 4-way (i.e.,
>->three or more switch controlled) circuit?  I have one such circuit in my
>->house that I'd like to control.  I notice that you can buy the non-active
>->half of the three way switch pair as a separate item; does this imply
>->that there is a way to use two of them and the three-way master switch in
>->a four way circuit?

This may seem like an odd response, but do you need one used as a 4-way?

Let's look at this schematically...(assuming ASCII is capable of rendering
schematics...)


hot      o-----o o-------o o-----o o------o
~ ------/       X         X       X        \-------,
         o-----o o-------o o-----o o------o        |
120      ^       ^       ^       ^        ^      (load)
VAC      3-way   4-way   4-way   4-way    3-way    |
                                                   |
~ -------------------------------------------------'
neutral

Each 4-way switch consists of a DPTD switch wired the following way:

                  .---------,
                  |         |
       >------o   o  ,--o   `----->
from 3-way     `----/-.          to next 3-way
               ,---'   \
       >------o   o     o   .----->
                  |         |
                  `---------'

(This crude drawing is supposed to represent the wires from the first 3-way
being crossed and connected to the other pair of contacts in the switch.)

Since this is the way a typical n-way switching circuit is wired, what
happens if you replace either one of the 3-way switches with an X-10
controlled device?  You have remote control.  Toggling any *one* of
the above switches controls the load.  I don't understand why you would
need remote control of more than one switch to perform only the one
function; or why you would specifically have to use X10 to control one
of the 4-ways.

I'm sorry if I missed your point, but I am not sure what your specific
application is (if it's not this).

-j
-- 
J. Deters
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