Electrical Wiring in the Home/combo switch


QUESTION: Hi Robert   I'm trying to switch a single pole light switch, which has only 1 wire in the box coming down from the light fixture, to a combo switch to add a outlet in the bathroom also. I've tried may different combinations of wiring on the switch but cannot get the outlet to work when the light switch is turn on the power on the outlet goes off, when the light switch is turned off, the power on the outlet turns on. Is there anyway to have constant power to outlet with only 1 wire coming in from the fixture supplying the power to both outlet and light switch or will I have to run another power source to outlet part of the switch?  Very confused!!!!

ANSWER: Lol...you have Me confused...ok lets start from the beginning first off there is no way to have any of this working with only 1 single wire comming from the light to the switch so can you please check again second unless you have a neutral in the box where 5he switch is going you will NOT be able to add a resepticle due to the fact you need a neutral to the resepticle.Now what i need you to do is look back in the box where the switch is and let me know exactly  how many wires there are,Also if at all possible take a picture for me and post it this way i can better understand  your situation.now just as a review you need to install a double/combo single pole switch
To switch of and on a light and the second switch to control a resepticle and there is only 1 wire in the box? Is that correct?  

---------- FOLLOW-UP ----------

QUESTION: Let's start over, I have a single wire with a hot black wire and a white neutral wire and no ground wire that were connected to a single pole light switch.  I want to change this to a combo switch to add a outlet, but with only 1 wire coming in to the box I can't seem to make it work. I need to have constant power to the outlet instead of the outlet only working when the switch is turned off. I don't want to control the outlet with the switch, only the light.

Hello Joe,
Ok i have a better understanding however you state you want to change the single pole switch to a combo switch in order to control  an outlet than you go on to say you dont want to contol the outlet with the switch however you want the light to control it???
So i take it what you want to do is have the outlet controlled by the light switch? Here are some options and solutions.
In order to add a resepticle to b3 controlled by any switch or even constant you MUST first have a neutral in that box where the existing single pole switch is as well as a constant (hot) without  a neutral in the box WHICH is in fact common to see you will NOT be able to do anything so lets first see if there is a CONSTANT & NEUTRAL  in that box and to do that follow the instructions below.

1- Turn OFF the switch and ONLY the switch.

2-remove the switch plate and switch and allow switch  to hang out the wall no need to remove any wires from the switch just yet.remember the switch is still OFF

3-with any standard electrical meter(and switch still off) that does Voltage place 1 lead to the box and the other lead to the top screw terminal of the switch that wire "SHOULD" be your constant and show 110-125v on the meter.if so BINGO you have your constant!!!

4-NOW put 1 meter lead on that constant wire that you just found and with the other meter lead go to each of the other wires in that box and look at the meter each time we are looking for the meter to say 110-125v again and when it does BINGO thats the neutral and than we can continue on with installing  an outlet

You see the meter will only measure voltage when it sees either a neutral or ground and thats why we are going to each wire you will ONLY get voltage  when it sees the neutral and the neutral wires SHOILD have a wire nut on them and it should be a MINIMU of 2 wires on that wire nut

WITH THE UNDERSTANDING THAT YOU NOW HAVE A CONSTANT AND A NEUTRAL.you can now go ahead and start the installation of that new outlet as explained below:

1-Y1-Your going to run a 12/2 cable from the switch box to where ever you want the receptacle and install your box as well

2-Let me know when you have the new box in the wall and the 12/2 cable from that box to the box where the switch is.

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Electrical Wiring in the Home

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Robert Tomasulo


I am here to answer ALL your questions regarding anything to do with home wiring such as Switches, Receptacles,Lighting, Main Distribution Panels, HVAC, Thermostats, etc; if it has a wire and in your home I CAN ANSWER IT. Whether its as simple as "why do my lights flicker?" Or as complex as I would like to rewire my house im here to help, in addition i can offer advice on remodeling a kitchen or lighting up you back yard as well as offering troubleshooting on appliances.


I have over 17 years in the electrical industry including Residential, Commercial & Industrial, Im also a certified HVAC technician as well as a certified fiber obtic technician.I am currently employed by the New York City Transit Authority as the Senior Electrical Maintainer and serve as the Relief Foreman for the electrical maintenance division for the past 12 years.I also hold many certifications, licenses and certificates in my field

FOA Member(Fiber Optic Association) UTU (United Transportation Union) IBEW (International Brotherhood of Electrical Workers) HVAC/TALK (Heating & Air conditioning troubleshooting group)

5 years of technical school after high school in electrical installation and design sponsored by Local 3 (IBEW) As well as over 17 years of hands on in the field training and education, and till this day im still learning, Not a day goes by that i don't learn something and if i feel i didn't i will open up a book to insure I DO!

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