I just bought an old house that I'm currently fixing up. Right now, the house doesn't have any power or water because I don't want to pay for power and water before I move in. I have a few chipped receptacles, but instead of replacing those few by themselves, I'm instead going to buy and install gfci outlets at the start of each circuit and move those old receptacles to where the chipped ones are. Of course though, I don't know which outlets are on which circuits, or even how many different circuits my house has for outlets.

How can I figure out which outlets are in the same circuit, preferably on the cheap? Is it even possible to do? I was thinking that if I had some sort of cheap ac power generator, I could attach it to the load wires and take note of which outlets start receiving power, but that sounds too expensive.

Actually, if the wires aren't connected to anything, could I technically just attach a 9-volt dc battery to the load wires? Would it basically just be like a square wave with really slow hz? How stupid is this idea?

  • So, your're fixing up an old house and you can't use power tools because you are too mean to pay for electricity. Have I got this about right?
    – Andy aka
    Jul 21 '17 at 9:15
  • @Andyaka Yeah, that's about it. The real fun part is when I'll have to sand the hardwood floors by hand. Really looking forward to it.
    – Prince_Tat
    Jul 21 '17 at 9:44
  • What kind of receptacles are these? Are they polarized: small slot for hot, large slot for neutral? Do they have a 3rd wire ground opening? Jul 21 '17 at 14:58

I'd use one of these - a tone tracer. They're mainly used by telecoms engineers to trace pairs in large multipair cables and junction boxes but they'll do just as well for this application.

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Though why you don't want to pay for electricity before you move in beats me. Surely you can get a plan where you just pay for what you actually use?

I'd have to advise against doing electrical work on the cheap though, it rarely ends well.

  • To put it simply, I'm pretty broke. The $200~ dollars for that Tempo tone tracer is more than I'm planning on spending for the electrical stuff (outlets, switches, etc.), floors, and walls combined. The bathroom will cost me most because it's completely terrible, and the doors will be pretty expensive. The doors I have now are so old that they actually have a (rusted) metal key slot that you can see through under the door knob. Anyways, I should be fine. 9 volts generally isn't dangerous.
    – Prince_Tat
    Jul 21 '17 at 10:15

Get a common DVM, variety of resistors and some orange wire nuts.

Go into the panel, turn off the main supply (yes, even if it's failing to deliver right now) and all breakers, even the ones not under test.

For each hot wire you want to test, pull the hot wire off the breaker (and neutral if wired to it) and wire-nut on a resistor between hot and neutral. If neutral doesn't go to the breaker put the other end of the resistor on the neutral bar. Use a different value of resistor (or resistors in combo) for each circuit. Make a list of all their values.

Go to each receptacle or light socket and measure the resistance. You should get one of those values. If you don't, search for loads which might be on the circuit, like light bulbs, illuminated switch plates, radon blowers, etc and get rid of them until you get an expected resistance.

  • 2
    It takes at least 500' of wire to get 1 ohm rsistance though (15V drop @15A, 12.5% drop) so I'd consider it unlikely unless he's fixing up OJ's mansion. Jul 21 '17 at 17:09

You can use the 9v batt or two 9v batt in series connection. Follow these steps:

  1. Remove all circuit breakers (or turn off) and make sure that there is no ac. THIS IS A DANGEROUS OPERATION! BE EXTREMELY CAREFUL!!!
  2. Mark every circuit breaker with a number (or letter) this will identify your circuit.
  3. Connect your batt to first circuit breaker and measure voltage on outlets. THE SYSTEM SHOULD BE OFFLINE FROM AC GRID!!! YOU HAVE TO BE SURE ABOUT THIS!! Connect (-) minus terminal of batt to AC - null (neutral) (N). Connect (+) plus terminal of batt to AC - Line (L) which is the output of circuit breaker. Then go to any outlet socket and measure the (N) and (L) terminals with a multimeter. if you see dc voltage equal to or a little bit lower than the batt voltage, then this outlet is on the XXX breaker's circuit.
  4. Mark the outlets with the breakers mark. Also you can note them on a paper if you wish.
  5. Repeat the process until every circuit is identified.
  • What do you mean by step 3? Do you mean to connect the battery to the wires that attach to the breaker? In which case I would have to remove the breaker to get to the wires.
    – Prince_Tat
    Jul 21 '17 at 9:39
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    If you are that confused then you should employ an electrician.
    – Solar Mike
    Jul 21 '17 at 9:46
  • @SolarMike I'm too cheap. I'll figure it out.
    – Prince_Tat
    Jul 21 '17 at 9:47
  • If I sounded a bit nonchalant, don't worry. I completely understand what I'm going to do and the potential risks. I can assure you, there is no risk of any AC power in my house, but nonetheless, I will be careful.
    – Prince_Tat
    Jul 21 '17 at 10:25

All you need is a continuity tester.

Since you don't have any power then you don't need to worry about getting shocked.

Make sure the main breaker is shut off. Make sure nothing is plugged it to any receptacles.

At the main panel, disconnect each hot wire from their breaker one at a time. Connect that wire to the neutral or ground bus.

Take your continuity tester to each outlet and check between hot and neutral or ground. The receptacles with continuity are on that circuit.

Lather, rinse, repeat!

Don't forget to put each hot wire back on the breaker it came from.

Good luck!


A toner/ tracer ( extech 24.99 / byes cable 19.99) will work well but the transmitter and pickup wand. THE POWER MUST BE OFF! This would be the quickest way to identify all the branch circuits. The only to know for certain the first outlet on a branch is to trace the wire or break the chain but usually the closest to the service panel is the first.

  1. Get a tone generator (Can be had for less than $20 at local home improvement store).
  2. Turn off all the breakers, including the main.
  3. Connect one lead of the tone generator to the neutral bus, and the other to one of the hot bus bars.
  4. Turn on one of the breakers that's connected to the hot bus with the tone generator connected.
  5. Wave the tone detector near electrical devices, and take note of any that cause the alarm to go off.
  6. Repeat steps 4 and 5, until all the circuits are mapped.

NOTE: For 240V circuits, you'll have to connect one tone generator probes to each hot bus.


Do you have a multi-meter with a resistance setting? If so, you don't need an external battery. The multi-meter has a battery inside which is used for resistance measuring. All you need in addition to the multi-meter is a long extension cord or set of cords.

What you do is flip all the circuit breakers to off. Plug the cord into any receptacle and pull the female end of the cord over to another receptacle. Measure the resistance between the hot slot on the receptacle under test and the hot slot in the extension cord. If the circuit is open (infinite resistance), then the receptacle under test is not on the same circuit. If the resistance is zero or close to zero, then the receptacle is on the same circuit.

This will not indicate the order of the receptacles from the panel.

Note that in some cheaply built houses from the 1970s (like mine) some wall receptacles are switched with a wall switch. Make sure that all single pole wall switches in the house are on (convention is that the up position is on). A receptacle which is switched by two 3-way switches represents a slight complication but that is rare and I think you can dismiss that possibility for the first pass.

  • 1
    Helps even more to have a bag of resistors, put a different value beween each hot and neutral at the breaker panel. "i'm reading 3300 ohms, that's circuit 9“ etc. Jul 21 '17 at 15:04

Use the 9v battery BUT make sure the supply fuses are removed.

The battery won't provide a square wave , but you will be able to measure the 9v on any socket that is on that circuit.

  • Should I remove the fuses or is it enough to just turn them off? Also, does it matter which wire I attach to the +/- part of the 9v?
    – Prince_Tat
    Jul 21 '17 at 9:21
  • Remove the main supply fuses and yes you may have to break the seals but you MUST remove them.
    – Solar Mike
    Jul 21 '17 at 9:40
  • Does this house have fuses or does it have circuit breakers? Jul 21 '17 at 16:24
  • Turn the main off or pull the main fuse is the same electrically
    – Ed Beal
    Jul 21 '17 at 17:01

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