Tracing House Wiring

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BolderBoy
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Tracing House Wiring

Post by BolderBoy » Thu Oct 12, 2017 3:21 pm

I have need to map my house's electrical wiring. Match up each circuit breaker with all the outlets, switches and lights it may control. Naturally, the breaker box is in a far corner closet of the basement (3 story, 1970s house).

What is the best way to do this?

I've tried using a Klein-Tools-Digital-Circuit-Breaker-Finder (Home Depot). It is utterly worthless in my house. It signaled on 4 circuit breakers, none of which controlled the outlet into which the transmitter was plugged.

The electrician's map which he placed in the breaker box is likewise worthless (except for the 220v wiring - he got that right).

Suggestions?
“Where you stand, depends on where you sit” - Rufus Miles | "Never underestimate one's capacity to overestimate one's abilities"

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CAsage
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Re: Tracing House Wiring

Post by CAsage » Thu Oct 12, 2017 3:26 pm

Two people with a cell phone and one of those little widgets you plug into an outlet to show power? Basically, walk the whole house, turning on/off all lights and check one room at a time. It's likely the house will be in zones; my 1940's era ranch has all bedroom overhead lights on one, outlets (inadequate) on another, living room separate etc.
Edit to add: if you are not graphically oriented, I found it helpful to make a long Excel listing with Room, device, location (e.g. Master Bedroom, West outlet, breaker 1 etc)
Last edited by CAsage on Thu Oct 12, 2017 6:12 pm, edited 1 time in total.
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renue74
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Re: Tracing House Wiring

Post by renue74 » Thu Oct 12, 2017 3:32 pm

I just went through this with a remodel I'm working on. I'm not an electrician, but I helped the electricians run wire in a 1935 craftsman bungalow.

After we ran the wiring and I had them wire the new breaker box, there were some "questions," I had about where some of the home run wires went, etc.

Your best bet is to turn each breaker on 1 at a time.

Then go around the house with a receptacle tester and test, plus turn switches on, etc. Mark breaker 1 and use tape and mark breaker 1 on each receptacle and switch. Continue for breaker 2, 3, etc. Painters tape or something....to know you have tested and found the breaker # for that particular switch or receptacle.

Obviously most circuits are in line and in the same room or adjoining rooms, but you will probably find some unique wiring in the house.

Slow and steady and you'll map out everything. It may take a few times to map each end point.

It helps to have a significant other at the breaker box along with mobile phones to talk. Makes the process easy.

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inbox788
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Re: Tracing House Wiring

Post by inbox788 » Thu Oct 12, 2017 3:33 pm

I don't think there are any shortcuts, pretty much one at a time systematically. If you only need to find one, binary search might help a tiny bit.

You can use another person and a walkie talkie, cell phone, intercom (some cordless phones have one) https://www.amazon.com/Panasonic-KX-TG4 ... B0073W70GA

Or you can do it yourself and take more time and get some exercise.

This is a great little tool to check the wiring as you go along as well:

https://www.amazon.com/Amprobe-ST-102B- ... 008E07HM2/
https://www.amazon.com/Electrical-Recep ... B0012DHVQ0

A simple tester AC tester may also be helpful.
https://www.harborfreight.com/non-conta ... 97218.html

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BolderBoy
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Re: Tracing House Wiring

Post by BolderBoy » Thu Oct 12, 2017 3:38 pm

renue74 wrote:
Thu Oct 12, 2017 3:32 pm
Your best bet is to turn each breaker on 1 at a time.

Then go around the house with a receptacle tester and test, plus turn switches on, etc. Mark breaker 1 and use tape and mark breaker 1 on each receptacle and switch. Continue for breaker 2, 3, etc. Painters tape or something....to know you have tested and found the breaker # for that particular switch or receptacle.
Bingo.

I have no one else to help me with this, so this will be how it has to happen, I guess.

Thanks.
“Where you stand, depends on where you sit” - Rufus Miles | "Never underestimate one's capacity to overestimate one's abilities"

iamlucky13
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Re: Tracing House Wiring

Post by iamlucky13 » Thu Oct 12, 2017 5:00 pm

Receptacle testing really doesn't take that long. You should be able to do the full house in an evening on your own.

I've been doing mine piecemeal in the midst of other work. I sketched out a rough floorplan and mark each outlet and light switch location on the floorplan with the breaker number.

When I'm done, I figure I'll go around again and write the breaker number on the back side of the cover plates, out of sight, but easy to access by removing 1-2 screws.

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AllieTB1323
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Re: Tracing House Wiring

Post by AllieTB1323 » Thu Oct 12, 2017 5:10 pm

inbox788 wrote:
Thu Oct 12, 2017 3:33 pm
I don't think there are any shortcuts, pretty much one at a time systematically. If you only need to find one, binary search might help a tiny bit.

You can use another person and a walkie talkie, cell phone, intercom (some cordless phones have one) https://www.amazon.com/Panasonic-KX-TG4 ... B0073W70GA

Or you can do it yourself and take more time and get some exercise.

This is a great little tool to check the wiring as you go along as well:

https://www.amazon.com/Amprobe-ST-102B- ... 008E07HM2/
https://www.amazon.com/Electrical-Recep ... B0012DHVQ0

A simple tester AC tester may also be helpful.
https://www.harborfreight.com/non-conta ... 97218.html
With the outlet ground tester you can also verify the outlet is wired correctly. When mapping our home I found someone was less than talented and had about half of the outlets with the hot and neutral leads switched.

123
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Re: Tracing House Wiring

Post by 123 » Thu Oct 12, 2017 5:12 pm

For starters, to get a rough idea, turns the lights on throughout the house, spread the table lamps around so there is one in an outlet in every room. Turn all the breakers off and then turn them on one at a time. See what lights each breaker connects with. Test the outlets in each room to see how far each circuit goes. Some circuits may light ceiling lights in more then one room or power outlets in multiple rooms. Don't forget to test the circuits for the dishwasher, garbage disposal, refrigerator, stove, vent fans, furnace, air conditioner, garage, and exterior lights/outlets etc.
The closest helping hand is at the end of your own arm.

killjoy2012
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Re: Tracing House Wiring

Post by killjoy2012 » Thu Oct 12, 2017 5:44 pm

If it's only you, then BolderBoy's method is probably the most efficient.
If you have a helper, it goes a lot quicker - one testing, one flipping breakers all while coordinating over cell phone or walkie talkies.

Another option is to plug noise makers into receptacles before heading down to flip breakers. e.g. a radio, multiple radios with different music/sound, etc. Flip the breakers til you hear it go off, or multiples at the same time. Doesn't help as much with lights...

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BolderBoy
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Re: Tracing House Wiring

Post by BolderBoy » Thu Oct 12, 2017 6:07 pm

killjoy2012 wrote:
Thu Oct 12, 2017 5:44 pm
Another option is to plug noise makers into receptacles before heading down to flip breakers. e.g. a radio, multiple radios with different music/sound, etc. Flip the breakers til you hear it go off, or multiples at the same time.
Didn't think about noise makers. Thanks, I'll add that to the process for tomorrow.

So, 2.5 hours later and I have about 1/2 the house done. There is little rhyme or reason to the wiring layout, so I'm glad I'm doing this. Also, in my office where I have a LOT of computers (etc) running, one of the outlets is shared by 3 bedrooms, 3 ceiling fans, hallway lighting (upstairs and down) and is on a crummy 15amp breaker! Fortunately I had an electrician add two separate 20amp circuits to my office a bunch of years ago (have yet to figure out which breakers they are on.) The suggestion about using masking tape with the breaker numbers on them to label EVERYTHING was the key idea that I couldn't think of myself.

Lots of good ideas here, folks - thank you very much. I'm fried for today; will finish it up tomorrow, then make the floor plan diagrams over the weekend (while incorporating some other of your ideas as well!)

Thanks to all!

Now to run back to Home Depot to return the Klein Tools device and buy something very simple that others have suggested. (hot and neutral reversed! gad!)
“Where you stand, depends on where you sit” - Rufus Miles | "Never underestimate one's capacity to overestimate one's abilities"

whomever
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Re: Tracing House Wiring

Post by whomever » Thu Oct 12, 2017 6:45 pm

I've had good luck over the years with a 'Circuit Detective' (mine looks like the cheaper $20something one amazon has). Sometimes it will only narrow it down to two adjacent breakers, but that still puts you ahead of the game.

On the bad side, it looks like the Klein one might just be a rebadged one of them. Maybe it's something peculiar to your wiring - lots of parallel lines or something.

(You do have to do the calibration lap, i.e. you run it over all the breakers, normal to the panel. On that first lap it will go off for several random breakers. Then, without shutting it off, you repeat. That time it finds the right breaker. I suspect it's looking for the max signal, but that's just a guess.)

These avoid resetting clocks, rebooting computers, etc when flipping breakers.

All that said, developing and maintaining a map is a good idea, and not too painful if you do it in one fell swoop. Do remember that you can wire outlets so each individual outlet (or half-outlet if you want to look at it that way) is on a different breaker.

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