Let There Be Light with the Circle Unbroken

NOTE:

The above picture is NOT mine (although the following pictures were taken by me). The configuration is similar to how my wiring appeared when removing the old fixture, so I'm sharing it only as a frame of reference.
I am not an electrician, nor am I pretending to be one. I am a moderate level DIYer. I have wired lamps and replaced ceiling fixtures, installed ceiling fans, and done things of this ilk for several decades. But if this experience has taught me anything, it's that electrical wiring situations can differ from one geographical area to another (i.e., due to building ordinances in different cities, states, countries, etc.), from home-to-home (depending on who does the work to the home), and--as in my case--from one location in the home to another.

I would never have gone to the lengths that I did to resolve this on my own if I didn't have a modern circuit breaker system in place. I'm not suggesting that you do any of it. However, if you are at your wits end trying to figure out a similarly confusing configuration AND have a modern circuit breaker system in place, it may save you some aggravation.

In any case, before removing or installing fixtures—and especially before touching any wires—make sure the power is off (not just at the light switch). Until I was sure which circuit breaker controlled the area I was working on, I turned the main power to my entire house off.

You will need a voltage tester (e.g., a multimeter) to identify your hot wires and your power will need to be on for that. I tried non-contact testers but found that the surrounding wires often tested hot even when they weren't--even with sensitivities adjusted.

Proceed with extreme caution. And once you have identified your hot wires, etc., turn the power off again before proceeding. Respect electricity, it'll go right through you and can be fatal.

Like "Easy Do It…" says: "When in doubt, hire it out."

For two weeks I tried to "crack the code" for replacing an old light fixture in the one place that hadn't been upgraded by our handy previous owner (it still had cloth wiring but in decent condition). 

I was replacing a vestibule light that was attached to a 15 amp single pole switch, and connected on a circuit that also powered a ceiling light in the adjoining bathroom and a standard grounded double outlet. All the wiring from the circuit was crammed inside the vestibule ceiling light electrical box.

Among my mistakes early on: 

-Not labeling (or taking a good picture of) the wiring/lighting set-up before removing the old fixture

-Thinking all black wires only go to black wires and white wires only go to white wires all the time

-Cutting the cloth wiring very short because I thought it was outdated/unnecessary

I eventually discovered that most of these errors in action/judgment are quite common for DIYers and am more of a stereotype than I care to admit.

So after using three voltage meters, several types/gauges of electrical wire, dozens of wire nuts, numerous wire configurations, and reading contractor/ electrician forums that explained the process (but unfortunately never illustrated it, nor posted a video on You Tube), I was almost ready to give up because I couldn't successfully achieve my goal.  But for me, giving up isn't an option.

My main issue was that out of all the wires (eight in all), only one was actually hot--120 on the multimeter with all others registering a big fat 0. (FYI: Scrutinize old fabric wiring very carefully because although they may appear to all be one dark color, often each set has one "blacker than" its partner. In my case, those were indeed THE black wires—even if they weren't all hot.)

In our case, the circuit required the one hot wire to be wire nutted to the other two black wires and their partner wires were to be wire nutted to each other to complete the circuit, providing current for all the items on the circuit to operate.

During my trial and error process, the vestibule light lit with the switch in the "off" position (and the other two items in the circuit worked fine) BUT when I turned the vestibule light to "on," the breaker tripped and nothing worked. 

THEN I got the vestibule light to work (as did the other two items in the circuit) but the light wouldn't turn off, as if the switch didn't exist. (I later learned this was because I was bypassing the circuit and working off the main line, independent of the light switch.) 

Finally I found this page (and the illustration above), which finally made sense. Although it wasn't comprehensive enough to encompass our particular circumstances, it was enough to make the "white wire becomes the hot wire" methodology understandable enough to execute.

So the picture above is what I did with my complicated 15 amp connection (should have been photographed step by step but I didn't think to "blog it" until all was said and done; below is an explanation as thorough as I can manage). With this kind of configuration, initially think of the wiring to the switch as independent of all other black and white wires. 

1. To provide working wire length to compensate for each of the fabric wires I had stupidly cut short, I wire nutted additional lengths of solid copper cable (Romex NM-B 14/2 wire with ground, which I stripped for black and white accordingly).

2. I wire nutted TWO new black wires to the one hot wire I had identified earlier.

    - One was wire nutted with the other two blacks (which had each been connected to the old black cloth wires) 

    - THIS IS MOST IMPORTANT (AND CONFUSING): I wire nutted the second new black wire from the hot wire to the white wire that connects to the power switch. (Yes. The WHITE WIRE.)  The white wire in the switch set then becomes "the new hot wire" and attaches to the hot wire screw on your switch.) Trust me, it sounds weird but look at the diagram because it worked.

3. The ground wire from the ceiling electric box was wire nutted to the ground wire in the light.

4. The white wire that was partnered with the one hot wire was also wire nutted to two new white wires

    - One was wire nutted to the white wire on the ceiling light

    - The second was wire nutted to the other two white wires (that had each been wire nutted to the dark brown cloth neutral wires)

5. The black wire from the switch was connected directly to the black wire in the ceiling light.

The vestibule fixture lights. It turns on and off with the appropriate flips of the switch. The bathroom ceiling light on the circuit works. The grounded outlet on the circuit works. No more tripped breakers, no more sparks. No more hassles. I'm giddy as a schoolgirl.

So check out this guy's site and support him. If he were within reach, I'd give him a massive hug. But for now, I'm giving him a huge shout-out and my undying gratitude.