Dimmer wiring help - red, neutral and ground doubts

Yikes! :scream:

I trust MY wiring, and no one else’s. Any wiring I didn’t pull myself from the panel to the box gets extensive testing before I trust it.

In preparation for our home sale, I rewired the entire house. It was knob and tube previously. I found many places where the previous owners had tied modern Romex to knob and tube in the walls. Not even a junction box hidden in the wall (also illegal), just wire nuts floating loose in the wall.


I also have to state for the record, that since I am not a professional electrician, I realize that electricity can be VERY dangerous, and I take my time when replacing switches.
I run back and forth to get the right breaker to turn off.
Even after that, I use a quality tester to make sure that there are no live wires.
I'm especially careful when I'm doing a multi-gang situation.
I try and label the "load" wires always.

If I'm not sure, I call in a pro that I trust.


Several years ago, our church group volunteered to help a relatively indigent person with wiring issues in their house. It was knob and tube that had been "upgraded" in places to Romex by tying Romex to the old wiring. Such a hot mess. We ended up starting an entire re-wire, in the middle of which the person passed away. House got torn down by whoever inherited it.


This :point_up_2:t2:, not the knob and tube wiring itself is why insurance companies are reluctant to insure homes with knob and tube, or will charge a premium for doing so.


In the pictures you posted, there are some things that should be apparent:

  1. the white wires that are all joined together (with a blue marrette) are neutral wires.
  2. the bare copper wires that are coming in to your gang box and are connected to the screws at the back of the gang box are ground wires.
  3. the switch on the left of your picture appears to be a three way switch with three wires attached to it (red, black, white), if this is in fact the case, none of these three wires are a neutral.

If these items were not immediately obvious to you, I would strongly suggest hiring an electrician. The items mentioned are very basic wiring principles, if you do not understand these basics, an electrical meter may be of little help.


Yup, that's what it could be...

I totally understand and recently found the previous owner of our house plastered over several junction boxes…. I just spent a couple days cutting them open and restoring the switches to their original boxes that had been plastered over. Then patching the drywall.

The previous owner of our house had some creative wiring done in here including hot glue to connect coax, masking tape connecting romex, even running 2 wires to one breaker in the panel.

I am happy there is hope for these enbrighten switches. It might just be the bulbs I got at Home Depot that flicker. They are eco smart dimmable LED but perhaps there is hope being you guys are getting them to work.

This is so common it's not even funny. I pulled every inch of wire in my new house and did extensive wire replacement in my old one. I think by the time I got done, the only knob and tube was to a light in the family room.... Hell, in one room, I found they had tied lamp cord into the knob and tube to run 4 outlets and those were joined with more lamp cord. :roll_eyes:


That's allowed by code, as long as the breaker is manufacturer approved for it (e.g. Square D QO series - "The 10–30 ampere circuit breakers have pressure plate terminals suitable for two-wire copper terminations."). You can also pigtail within the breaker box.

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oh this is a very good point and frankly did not strike me yet. I will check this part, but can this then mean that perhaps there are two "sets" of white wires in my box?... one being the neutral and other being traveler? i will have to test which is neutral vs traveler.


Neutral will likely be the gang of white wires with a wire. A travel wire will be separate.


This is really good advice.


The city inspector found it when I was doing additional work he was like what is this? I am like I have no idea it was like that when we moved in. He made me put in a small wire and then put a nut to connect them. The breakers we have can't have more than one wire under the screw he said.

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Pigtail fix. The other appropriate choice in this situation is to use a tandem single-pole breaker (sometimes called a twin breaker).

What @mikes was referring to is illustrated in the photo below. Square D (and I think Eaton) make single pole breakers designed for two conductors. The breaker below is rated or a single 8-14 gauge conductor (Aluminum or Copper). Alternatively, it can take two 10-14 gauge Copper conductors.

That is good to know! My box is Siemens and just has a screw that pushes down on to the wire directly it doesn't have the little arms like the one in that picture. I also would assume he wanted to be done with the pigtail instead of me going to the store to get a double breaker. LOL

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Thanks a lot to the extremely helpful guidance and pointers from this thread!! Today I finally did the installation and was successfully able to put in my brand new Zigbee switches!!! i took my time to use my NCV and multimeter to carefully identify and test each wire. I labelled them as I went forward. In the process...discovered that my basement bathroom is actually not a part of the basement circuit breaker :stuck_out_tongue:
I added a small pigtail to my neutral wire set...from that pigtail I was able to cleanly take out additional two wires for my 2 switches. All good now!


A bit off topic, but I thought of this when you mentioned that you discovered that it was on a different breaker…

One thing that I did many years ago was identify what breaker controlled what switches and outlets. I did this for all of them and put the result in 2 forms:

  1. Plan of the house with all outlets, lights and utilities (oven, stove, water heater, etc.) with the breaker number on each. I have a copy printed that I keep next to the breaker box.
  2. Spreadsheet with an indication of what is on which breaker - I have that one taped in the breaker box door.

Now whenever I need to make any electrical updates, I know exactly what breaker to turn off and what other device will be impacted. Very useful!


This is a laborious but fruitful task. But you know, it always amazed me how often you see panels that are poorly labeled. Granted changes occur and those aren't always an electrician's doing...but how many times do you open a box and see A LOT of labeling missing or poorly done and wonder...."why doesn't the code & inspection insure that this labeling is done to an high level of fit & finish as of Day #1".

Of course maybe this is more a thing of the past than today.

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