3 way x10 switch problems


Active Member
I replaced a pair of 3-way switches on the stairway with X10 3-way switches last month. My wires don't have different colors like modern wiring, so I just connected wires like they were on the old switch.

I'm not sure what I did wrong, but the switch is not responding to my x10 commands, and neither is the other x10 switch (for the entryhall) in the double gang box. They both still functions as a normal switch though.

Can anyone direct me on how to fix this problem?
hgupta1-Did you ever get the switches to work, or did they just stop?

When I wired in my 3-way switches, I just could not wire the switches like the old ones. I used the Switchlinc switch and a Switchlinc slave switch.

The way mine was connected, power entered on one switch and the load was connected on the second switch. When the x-10 switches and slave were installed just as the orignal, when 1 switch was pressed, there would be no power to the second switch (this is how 3-way switches work by design)

To fix the problem, you need to figure out which switch has the power, and which switch has the load (light). Then tie 1 wire that runs between the two boxes to the power (this way both boxes have power all the time). Then connect the neutrals, tie the other wire to the travler, and connect the load

That is how I had to do it.

I never had the switches working properly with x10 signals. They work ok as regular 3way switches though, which is why I let them be for over a month.

I think I need to clarify my first post though:

There is an x10 slave switch at the top of the stairs.

At the bottom of the stairs is a double gang box: one x10 switch for the entrance hall, and one x10 3way switch that is the master for the upstairs slave switch.

The entrance hall x10 switch used to work great until I replaced the pairs of stairwell 3 way switches with x10 switches.

none of them now accept x10 commands


Anyways, I have a multimeter: is there a way to use it to determine which wires are hot and which ones are neutral, and which ones are for the 3way slave?
Your wires have no colors? Very strange. Hot is easy. Set meter to 300v range, connect one probe to ground and test for 110v at each of the wires. In 66% of traditional 3-way wiring circuits, one of the two switches has a connection to hot. There will be no wire running to the other switch that's always hot. That's why I can't understand how you could "hook the switches up the same way". Anyway, my xp is with switchlincs. The first thing I do is designate the location of the master switch. this must be the same box where the light feed ends up. There needs to be an always hot connection/neutral connection to this box as well. Sometimes I get lucky and there's a 3 wire cable going to the slave box. If this is the case, then whichever box has hot sends that and neutral to the other box over black/white. Red becomes the signal. More often than not, its more complicated as valid 3-ways can have the load first, in the middle or at the end of the wiring run.

If the light's at the beginning of the run then the pooch is pretty much screwed since hot comes out at the light fixture and there's generally only a two wire cable going to the first 3 way switch. Sometimes you get lucky and there's also hot/neutral in that box too.

If the light's in the middle, the wiring is almost as complicated since hot exits at one switch, there's a three wire to the light and a three wire from the light to the other switch. Often times, the end switch has no power so you're stuck needing 4 wires from the first switch to the light. A "to-code" solution requires running more wire to the light. However, there are not-to-code solutions as well (I've heard)

Anyway, if this all sounds like gobble-de-gook, I highly recommend that you purchase a copy of the Black and Decker "Complete guide to home wiring". They list most common circuit wiring diagrams on page 126-166. The three common 3-way techniques are listed there on pages 163-164.

What kind of X10 switches are you using btw?
Well, there are colored wires, but I don't trust the colors because this house was built in 1920 with the old style knob and tube wiring, and where the romex ties in with the older wiring, I am not sure that electricians followed current color coding schemes. You will see this in my diagram of my wiring where a piece of black wire ties in with a white wire to connect with the blue wire on the 3 way master switch.

The reason I was able to hook up the 3 way switches the same way as they were is becuase I replaced regular 3 way switches with x10 3 way switches. Although I did't trust the colors of the wires, I used the colors of the screws to guess which ones were hot.

My switches are made by X10. The three way switch is the WS477.

I have uploaded a diagram of my wiring that I am talking about. Hopefully this will clear up any confusion:


I really appreciate your thoughtful and detailed explanation. Thank you so much. Hopefully we can work out what is wrong.

Thanks for the link.

I did some examining and tracing and have dermined that the knob and tube wire at the top of the steps runs directly to the light in the stair well. The black and white wires at the top of the steps are a pair within a length of romex that runs to the bottom of the steps. The white wire on the the right side of the gang box is hot.

When I connect the white wire at the bottom of the steps to the knob/tube wire at the top of the steps, the light turns on.

Clearly the romex is the pair of common wires

Bottom line:

I have the hot wire at the bottom of the steps, and the load wire at the top of the steps, and the romex running in between them for

Following the directions that came with the switch, I still can not get the x10 commands to work. Further more, the other x10 switch in the gang box works great until I reconnect the three way switch.

Any ideas? Do I just have a bad switch?
Wow, nice link on X10 3-ways Guy!

Anyway hgupta1, as far as the signal issue goes, I've never used the X10 switch you installed so I'm not sure if it is an X10 transmitter or not. Nevertheless, maybe its attenuating X10 signals to the point where the entrance hallway light can no longer receive them when the ws477 is installed. Make sure of this by disconnecting hot from the ws477 then testing to see if the hallway switch is responding to x10 again.

If the entrance hallway switch X10 command fails when the ws477 is connected to hot and works when it isn't, then unplug any computers/UPS devices/tvs/stereo equipment, turn on your electric clothes dryer or electric stove if you have one and retry the test. If the hallway switch now works when the ws477 is connected to hot then you have a signal degradation issue and a strategic boosterlinc placement, signal coupler or X10 filters on your unplugged devices will probably fix it (if you already have a coupler installed, then skip the dryer/range part of the test).
Thanks kwilcox,

I disconnected the hot from the WS477, and the hallway light works fine. I already have a coupler on my dryer, as well, so I wasn't able to perform the test that you recommended.

I did try swapping the slave and master switches, (so that the master switch is at the top of the steps now) and I found that my I am getting much better response from other x10 devices in the house.

I am ready to give up on the three way switch. I think I am going to put a regular 2 way x-10 switch in its place downstairs and tape a palmpad controller to the wall upstairs, unless someone has a better idea.
Good, you've got a phase coupler already. However, you may already have several "signal suckers" in your house and your ws477 was simply the straw that broke the camel's back. I'd still try disconnecting all your known signal suckers like stereos, computers and TVs (don't just turn them off since that won't do anything).

Pay special attention to devices that are on the same circuit as your hallway entrance light. With a house as old as yours that may very well be half of the entire building.

If unplugging everything results in the hallway entrance light working with the ws477 connected then start plugging the stuff back in one at a time followed by a test repeat. Eventually, you'll be able to isolate the worst offender(s) and then just purchase filters for them.

If unplugging known signal suckers fails then another very likely possibility is that the ws477 itself is bad and not only won't respond to X10 commands but also destroys other X10 signals when its connected. Do you have the luxury of owning a spare ws477 switch to swap in?
You are right about most of the house running off the same circuit!

I'll try unplugging tomorrow and seeing if I can isolate any signal suckers. I know that I have a few other devices that do not respond as well as they should. I really am annoyed at the price of those filters though: It seems like a lot of money for something that doesn't "do" anything!

Does older wiring not transmit x10 signals as well as newer wiring? I wonder if I should get a TI-103 or a boosterlinc.
Alright Kwilcox! You were right on!

I had installed the 3 way switch correctly but a few devices were sucking up my x10 signals, including an older tv, an ionic breeze, my laptop power supply, and the computer in my office.

I unplugged all of these, and the x10 devices worked great!

So, I bought a couple of these5 Amp filters from AutomatedOutlet.

I added a filter to the TV, and ionic breeze, and plugged them in and everything worked great. And then I added a filter to the computer, and plugged it in, and my x10 devices stopped working.

I tried a known working Smarthome filterlinc for the computer, and it did not perform any better.

For now, I have the computer unplugged, but why would the filter not work, and what can I do?
hgupta1 said:
I tried a known working Smarthome filterlinc for the computer, and it did not perform any better.

For now, I have the computer unplugged, but why would the filter not work, and what can I do?
I had a really, really cheap Fry's no-name brand computer power supply that put out so much noise in my power line that even a filter didn't help any.

I run antec supplies exclusively now (still with filters though). HERE is one of my favorite "signal suck" threads.

The only way I found all of mine was to use a signal meter and go around unplugging everything in the house. Believe it or not, with a meter I found out an "Stanely" X-10 mini controller was actually a signal suck (go figure)!
Ughh...this is a super cheap power supply that I just bought two months ago. And I was so proud of being a frugal consumer.

I don't have a UPS on that computer. Do those usually help clean up the signal, or do I have to go ahead and get a new power supply? I really don't want to pay that much for an Antec power supply.

Can I rent a signal meter somewhere?