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bergs4 07-27-2009 03:11 PM

Troubleshooting Three Way Switch
 
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Hello,

I am having problems identifying wires in a three-way switch. Background -- I am in the process of replacing two three-way switches which control a receptacle. Inadvertently, I removed one of the original switches without noting the proper wiring. :mad: As an unfortunate bonus, there are four wires (three different cables) going into this box. I'm assuming that two of the wires were attached to the same screw on the original switch (which I know is bad to do). My question is -- how do I properly identify the wires for wiring of the new switch? I have posted a picture for clarification.

Also, I replaced the other three-way switch controlling the receptacle and rewired it exactly as it was before.

adpanko 07-27-2009 05:17 PM

The two wires that are in the same cable are most likely the two wires that are connected to the traveler terminals on the switch you already replaced. So they should go onto the traveler terminals on the new switch. The other two are likely 1) the hot line coming in from the panel and 2) another hot wire that connected to that and went off to feed somewhere else in the room. So you want to pigtail those together, along with a third piece of wire, and attach that third piece to the hot terminal on the new switch. That should be it. (if you want to test to confirm that the other two wires are as I mentioned, you can turn on the power while the wires are still not attached to anything and touch a volt tester to each wire separately while touching the other end of the tester to the box, and one of the wires should have juice while the other one doesn't...but obviously be careful not to touch the wires to anything else while the power is on)


But I noticed there are no grounds in the boxes. You should cut a short piece of bare wire and attach that wire to the ground terminal on the switch, and the other end should be attached to the box itself.

220/221 07-27-2009 05:32 PM

Quote:

there are four wires (three different cables)
:jester:

Quote:

You should cut a short piece of bare wire and attach that wire to the ground terminal on the switch, and the other end should be attached to the box itself.
:jester:

All kinds of bad info here :laughing:

I can't see crap from that pic. Maybe it's my monitor??? This may be knob and tube instaed of cable????

And there is no ground available so attaching a ground wire to the box will be pointless. Plus its a metal box and the screws would suffice...if there were a ground present.

bergs4 07-27-2009 05:58 PM

The house has no ground; it was built in 1946 and the wiring hasn't been updated since then. Unfortunately, grounding is not an option for me right now until I have an electrician come in to update my service panel -- I was told wire to a cold water pipe and grounding rod is not an acceptable means for grounding in the interim.

It does appear that the two wires in one cable (the wiring is not knob and tube; the "cable" is some sort of ruberized fabric which I guess they used pre-romex type cable) are the travelers. However, since there is no ground, is there a different way for me to be sure that the remaining two wires are in fact the common (which need to be pigtailed together)?

Thanks.

220/221 07-27-2009 06:15 PM

OK. Forget everything about a ground.


I've never seen cable with only one wire. That's why I assumed knob and tube. They would often use these insulating sleeves to enter JB's.

I see that three of the wires were obviously hooked to the old switch (they have loops or rings on the end) but I can't see the end of the fourth wire.


If all four wire were attached to the old switch, chances are that the two together are the travelers and the two separate are power (common). Hook it up that way and try it. It's not going to hurt anything.

I still think it's K&T :yes:

bergs4 07-27-2009 06:31 PM

Okay -- that makes complete sense. Yeah -- all four wires were attached to the old switch.

It's funny, other people have said it's knob and tube but under the house and everywhere else I've encountered the cable/wiring there aren't any of those white circle things (the knobs I presume?) or bare wires that I've seen in pictures of knob and tube wiring. In any event, it goes without saying that in 1946 they did these things a lot differently. Maybe I'm missing something:(

Thanks for the help.

bergs4 07-27-2009 07:10 PM

Okay, so I wired the switch as specified and it controls the receptacle without any problems. However, the other three-way switch now doesn't work (this is the one which I wired as it was originally wired). I have noticed however, that if the switch is flipped part way -- it works (half-way between on and off). I'm guessing the switch is bad, or could it be something else?

J. V. 07-28-2009 12:20 PM

Why don't you rewire this house. It looks like a fire waiting to happen IMO. I would be concerned to live in that house. Thats just me.

bergs4 07-28-2009 12:43 PM

That's the plan as soon as I have the $$$$. At least the house is brick...

Stubbie 07-28-2009 01:23 PM

The other wire has been cut off in those cables. My experience has been that this type of wiring leads to other problems in the house such as shared or borrowed neutrals, combining hot wires of two branch circuits that back feed branch circuits and many other issues. But if you want to keep what you have and get it back to original you will have to use a combination of voltage tests and more importantly continuity test each wire box to box in the switched receptacle part the circuit to determine what wires go to where. If you know what your doing you should get it back working in about an hour or less.

bergs4 07-28-2009 02:13 PM

You know, it's funny you say that, because last night I realized that there is another, seperate switch, that when in one position completely disengages the two three ways switches and receptacle. As I thought about it, I realized that this wasn't a problem I created but existed when we bought the house.

Also, I thought those cloth cables seemed rather large for only one wire. Needless to say, the wiring in this house is shady. Another thing I noticed was, instead of pigtailing, the original installer simply removed some insulation from a piece of lead wire, ran that wire under a screw on the switch and continued the same wire to another switch (if that makes sense).

I'm thinking I need to have the wiring upgraded sooner than later. Anyone know what the rough cost would be to have an electrician replace the panel (the existing panel is 100 amp fuse)? And is pulling the wiring something I might be able to do under his supervision to save costs? I'm near Sacramento, CA.

Stubbie 07-28-2009 03:03 PM

Quote:

Originally Posted by bergs4 (Post 307827)
You know, it's funny you say that, because last night I realized that there is another, seperate switch, that when in one position completely disengages the two three ways switches and receptacle. As I thought about it, I realized that this wasn't a problem I created but existed when we bought the house.

Also, I thought those cloth cables seemed rather large for only one wire. Needless to say, the wiring in this house is shady. Another thing I noticed was, instead of pigtailing, the original installer simply removed some insulation from a piece of lead wire, ran that wire under a screw on the switch and continued the same wire to another switch (if that makes sense).

I'm thinking I need to have the wiring upgraded sooner than later. Anyone know what the rough cost would be to have an electrician replace the panel (the existing panel is 100 amp fuse)? And is pulling the wiring something I might be able to do under his supervision to save costs? I'm near Sacramento, CA.

What you propose is really not realistic, electricians just can't work that way and make a living. I know it sounds good to you but I don't believe you will find any takers. It is impossible to give you an estimated cost for a panel upgrade without seeing what you have and what needs to be done. If you just want a circuit breaker panel as a replacement for the fuse panel then likely around 600 to 800 dollars and staying at 100 amps. But without changing that goofy wiring in your house it really doesn't make sense without rewiring the house and upgrading the panel. 100 amps is also the minimum for a single family dwelling and 200 amps is becoming the standard now days. You likely will have to change the service entrance also to go to 200 amps. So I'm not going to throw numbers at you as it would be pure speculation on my part. Get some estimates from a few electricians /contractors then come back here and we can help you decide if they are fair estimates. Also size of your home would be helpful and what appliances you have that are electic, such as stove, heating, dryer etc... also consider what you might like to add in the future. This is in order to make sure you do not need a 200 amp service over a 100 amp service.

adpanko 07-28-2009 03:35 PM

I had our old 1960's 100 amp service upgraded o 200 amp. All the wiring in the house is/was already NMB, so he didn't touch any of the wires in the house. He swapped out the old box and breakers for a new box and breakers, reconnected all of the wiring for each circuit, ran a ground from the box to the water supply pipe (which was about forty feet and not an easy straight run, replaced the meter on the outside and the piping running from the box to the service cap, and replaced the wiring from the service cap into the box. I think it cost 1,800 cash, and it tooks two guys the better part of a day. Except for running the ground to the water pipe, everything was straight forward and easily accessible. This was two years ago and in NJ. I don't know how much more or less your situation in CA would be. But using this as a gauge, I would assume that 2k is a decent benchmark, give or take, for replacing the service (but not rewiring the whole house).

bergs4 07-29-2009 12:28 AM

Stubbie / adpanko --

Thanks for the insight. It's nice to have somewhat of a baseline. I think my biggest concern with respect to rewiring is the difficultly of actually doing it (not the technical, but the physical). The house has plaster walls, and as I guess was common during the time it was built, they put blocking at four feet. So, there's no straight shot to drop a wire from the attic / pull one up from the crawlspace. Is there a way, short of putting a lot of holes in the plaster for an electrician to pull wire through walls with blocking in it?

If only the home warranty I got covered rewiring...

adpanko 07-29-2009 09:47 AM

Sounds like there is no easy way to cleanly run wires up through the walls since there is blocking. Do you know if your house has balloon framing or platform framing? It will be a lot of work, but you can get creative with ways of building soffits, chases, knee walls, or any other means of creating a space to run/hide wires if you can't run them behind your walls. You can't as easily cut holes and patch plaster like you can with drywall, so I wouldn't try to start cutting into your walls out all (except where you want to change or add an outlet).

If you want to be ambitious, have a lot of time and have decent drywall skills, you could bust up all the old plaster down to the studs, then rewire everything and drywall it. Granted, this is a HUGE increase in work compared to just changing out wiring, but seeing as your wiring appears to be a potential fire hazard, it might be worth the time and hassle. I did this in our old house about five years ago, an 1890's that had plaster walls and a mix of assorted types of wiring from over the last century. There was some defunct knob and tube, some BX, some of the stuff you have in your picture, and some Romex (there was even gas pipe running through the walls to some old gas lantern fixtures). The service was upgraded by the previous homeowner, but the wiring throughout the house wasn't. So I went a room at a time, breaking out plaster, rewiring and adding insulation (since there wasn't any). Then drywall, some trimwork and done. It was a pain and time consuming, but after each room was done, I was able to sleep well knowing that at least that much more of the house was safe (and it increased resale value too). But I had no kids yet at the time, so I had much more available time. Now would be a different story.


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