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Participant

Join Date: Oct 2013
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How Do I Trace Wiring From Breaker To First Outlet/Light On The Circuit

10/16/2013 3:50 PM

First, this is a home built in 1922. Still has some, although limited, know and tube wiring in it. The Panel is on the main Floor, and is wired with older 2 conductor wire down through the basement, where it is spliced into Knob and Tube wiring. From the splice, the Knob and Tube the runs through along and through floor joists until it goes straight up through the floor. This is the first issue. I know it powers all the lights and outlets on the second floor (2 bedrooms and a small bathroom). What I cannot determine, is where, specifically, the knob and tube connects to the 2nd floor circuit. I took a look at the wiring on the second floor(removed outlets and looked at the wires) and find they are not knob and tube, they are a more recent and satisfactory wire. What I need to do is replace all the knob and tube, but to do so, I have to find how the wire runs from the basement to the second floor and exactly where on the second floor it connects to the wiring. Is there a way to do this without having to cut into the plaster and lath walls which are in perfect condition and I would hate to have to destroy. Short of finding where it connects, I'm not sure what to do next.

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#1

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Cicuit

10/16/2013 4:10 PM

I don't know about this site, but I'd try one of these first.

http://alltoolssupplyinc.com/home_files/zircon.html

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#2

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Cicuit

10/16/2013 4:59 PM

The best way is to just disconnect all the old wiring and leave what you can in place, then run the new wire and conduit in the most efficient manor.....You can fish wires a lot easier than removing old ones.....It takes planning and expertise.....I would use this opportunity to bring everything up to code....

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#5
In reply to #2

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Cicuit

10/16/2013 7:54 PM

I have to agree with SolarEagle. Don't bother trying to use the knob & tube. Pull out and replace what you can. Short both ends of what you leave in place. That'll reduce the likelihood of leaving anything live behind. Put some time into bringing it all up to code.

Good luck.

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#11
In reply to #2

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Cicuit

10/17/2013 8:17 AM

GA Solar... I've redone a few houses and have always left the old wiring in-place - unless I do have to replace the L&P, then I pull whatever I can get to easily, otherwise it stays.

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#16
In reply to #2

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Cicuit

10/17/2013 1:05 PM

I agree with Solar. I also agree that a circuit tracer could be used. The problem is, patching up old stuff repeatedly just ends up in a mess. I personally don't trust old mix/match/patch jobs. Whenever I have been involved in re-wiring, I take out the old wire. I end up with a lot more old wire than I use new. That's because I re-plan and re-lay the wire in the best and most efficient/logical fashion. Once I do that I know:
The house is safe from electrical fire.

Everything is properly routed.

Wire is all rated for its proper cicuit and application.

Breaker box and breakers are all appropriate and etc. also.

Granted, that's a "big" project, but for me, it has always been the right way to go.

On the other hand: Use a circuit tracer, find the point you're looking for, and kludge something in - is done a LOT. That's how breaker boxes and wiring eventually end up looking like a spaghetti fight.

But that's your call - it's your house. If you're patching and kludging, I just recommend verifying that at the minimum each circuit or section you work on is up to date, up to code, and appropriate in all other ways.

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#3

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Circuit

10/16/2013 5:44 PM
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#4
In reply to #3

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Circuit

10/16/2013 5:53 PM

basically test equipment like this sends a signal down the wire of your choice, you just use a hand held receiver to detect the signal and you follow that signal until its been traced out

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#6

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Circuit

10/16/2013 10:19 PM

Before burning the house down spend some money and hire an electrical contractor to rewire the hole house. Post and tube is nothing more then a excuse to burn the house down.

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#7

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Circuit

10/16/2013 10:59 PM

Cable tracer is the easist way, 2nd method you need two people, long lead , radio and multimeter or bell testers.If you dont know how to go about using them , hire an electrician.

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#8

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Circuit

10/17/2013 1:14 AM

"I'm not sure what to do next."

What to do next?

Do yourself a favour that will give your peace of mind knowing that your home and family are safe... Get a copy of Yellow pages and call a contractor, or ask your friends or neighbours do they know someone, go to Home Depot and ask can they recommend anyone, call the local city department and ask them.... but for the love of Mary DON"T touch it yourself.

It took me (and others in this forum) over 5 years as an apprentice to learn my trade and you'd like us to impart ALL that knowledge and experience to you in a few paragraphs?

Miracles we can do.. the impossible takes way longer!! Yellow pages is the way to go here.

I would like you to remember, electricity, you can't see it, you can't smell it, you can't hear it... but when it bites it could be fatal...Be safe my friend!

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#19
In reply to #8

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Circuit

10/20/2013 7:16 PM

Totally agree. Spent 45 years as a trouble shooter in a small town in No. Cal. Can't believe all the potential fires I found. Too many 'handypersons" As Birch says there are so many tricks to the trade in order to do things right.

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#9

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Circuit

10/17/2013 1:57 AM

Is the limited knob and tubing enough to qualify for a MUSEUM destination? Than that is the way to go. Perhaps you can make money out of it with an admittance fee for visitors?

But if you decide to live there, throw all that stuff out, after disconnecting the power first. There is enough sub standard material to replace it with. The ants will love the new piping.

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#10

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Circuit

10/17/2013 3:32 AM

It's overdue for a total re-wire. Call a few contractors and start getting quotations, otherwise a measure of unpopularity with the fire insurance company is a certain eventual outcome.

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#12

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Circuit

10/17/2013 11:24 AM

As an EE using a lot of electrictions over the years, do not go blindly into picking one at random from the internet or yellow pages. Learn as much as you can about the wiring and ask other owners in the same area for references. Interview the contractor and find out their approach and whether you can live with it. I find the smaller contractors are often better than the larger ones for this purpose. find out how much removal of walls they will do and whether they will repair the holes or whether you will need to hire a separate contractor for that. You should write down what you want before contacting any contractor. You should expect a wide variety of prices. The highest and lowest prices are probably very poor contractors and don't know what they are doing. I would talk to at least 5 different contractors before picking one and be sure to check their references for similar work. The questions you asked lead me to believe you should not attempt this yourself.

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#13

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Circuit

10/17/2013 11:32 AM

The best way to achieve your goal is to do what has been suggested by others. If you try to use the knob and tube as a junction point, the old wire insulation WILL fall off and you will have to replace it anyway. Replace all the old wiring period.

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#15
In reply to #13

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Circuit

10/17/2013 12:50 PM

Note that if it original knob and tube, there will not be any insulation on the wires at all. Once insulation was added the knob and tube was done away with.

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#14

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Circuit

10/17/2013 11:36 AM

A circuit tracer will put a signal on all devices for the branch, not just the first. Logic may or may not come into play when trying to determine the first device.

When you say satisfactory, I assume you are talking about two wire with ground. My question would be: where did "they" land the ground? Is it floating in the sheath, or worse, is it bonded to the neutral from the panel at wherever the new wiring was spliced in? That must be determined!

A circuit tracer and a polarity checker may be a good investment for your, and are a heckuvalot cheaper than hiring a full-on contractor. Those two tools will help familiarize you with your houses wiring. Otherwise, after the burn-rate and onion dues are figured in you will be into a huge bill before you know it...just for one guy's opinion.

Hiring an electrician's opinion or paying for the work is a good idea if you are completely helpless. But, black+decker and a host of other companies wouldn't be printing books for DIY'ers if it were rocket science!

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#17

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Circuit

10/17/2013 7:53 PM

Patrick, this is one of those jobs that if you have to ask how to do it, you really shouldn't. As most of us here know, 95% of house wiring is mechanical, but it's the electricity that causes the fires when it leaks.

Seriously though, the NEC (National Electric Code) no longer allows the use of knob and tube as a wiring method, therefore you can't legally extend or connect to it. If you do and there's a fire, your insurance will not pay any claims. If you try and sell the house and some sharp-eyed inspector sees what you've done, you'll have to remediate the whole electrical system before any sale takes place.

As others have said, leave this job to the pros; pay now or pay much more later.

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#18

Re: How Do I Trace Wiring From Breaker To First Outlet/Light On The Circuit

10/17/2013 8:40 PM

Patrick McCabe-

Another thing you might want to consider is using a "Circuit Breaker Tracer" to attempt to trace down the physical location of the old wiring. This might be very important if there are any junctions within the wall on the tube and knob wiring. These could lead to other outlets which you are not aware of that might be on the same circuit. With many old homes they put in a minimum of wiring and fuses.

Circuit breaker tracers are usually used by plugging a sender unit into an outlet of the outlet whose circuit breaker, (CB), you want to find. The receiver is then slowly moved over the row of CBs in the CB panel with it set for most sensitivity and a tone listened for. When the tone is heard at one CB that is the one that controls the circuit the sender is plugged into. If the tone is over several CBs, this is repeated with the sensitivity lowered each time until the receiver only hears the tone over the correct CB for the sender.

By plugging the sender into one of the outlets you will generate a signal in the circuit. Set the receiver at its most sensitive setting and sweep the walls for the wires. Either start at the fuse, CB, or outlet whichever is most convenient. Since the wires behind the wall are acting as an antenna for the tone signal you should be able to trace it this way. It is easiest to start from a known fixture.

This procedure is similar to a stud finder except you are searching for a extremely low power radio signal instead of a change in mass behind a sheet of wall board. For me this method has proven itself to be very handy and time saving for doing just what you are now confronted with including NM wiring hidden in walls that are connected with CBs. It is much handier to know all that is behind the sheet than to work with what you think is behind it.

Circuit Breaker Tracers are available at the big orange and blue boxes, Milwaukee brand I think), Radio Shack, and Electrical Supply houses. They usually run between $25 and $50 each. Watch out though, once others find out you have it they will want to "borrow" it instead of buying one themselves.

Good Luck, Old Salt

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