Spliced Electric Wire Only Works When Breaker is Off

Hi everyone...

I'm going to start off by stating the obvious: I'm not an electrician. I apologize if I'm not using the correct terminology, but I'm learning!

My Story: I mounted my TV on the wall and didn't want any wires hanging down from it so I decided I needed to put in a power jack behind the TV. I've done some research online, talked to an electrician that works at the local Home Depot and purchased all of the necessary tools and equipment. (I understand that this still doesn't qualify me as an electrician, but I would like to learn how to do this.)

I cut a hole in the wall behind my TV where I wanted the power jack and inserted a blue plastic remodel box and ran new 12/2 electrical wire from the remodel box to the attic.

I found a 14/2 electric wire in my attic and traced it back to my breaker box to a 15 amp breaker (It supplies power to the outlets in two bedrooms.) I cut the power to it and spliced it to my new power jack using wire nuts and a covered junction box.

The Issue: After I got everything connected, I went down to the breaker box and noticed that a breaker had tripped that controlled the lights and power in two adjacent bathrooms. I also noticed that once I had all of the breakers on, all of the pre-existing outlets worked but my new one did not.

So I cut the power to the original breaker and thought I'd look at my connections again. When I was making sure there was no power going through the line so I could work on it, I found that it was still hot. So I checked my new outlet again and it read 120v but all of the pre-existing outlets had no power...

Why would 2 breakers control one wire? What am I doing wrong?

Additional Info: My house was built in 2002 and completely professionally remodeled (electric and all) in 2011. Everything meets or exceeds code. When I added my new wire I connected black to black, white to white and ground to ground.

Any help would be greatly appreciated!!!!!!! Thanks!

 

If you are really in the US you installed a receptacle not a power jack. If you talked to an alleged electrician at BigBox heaven knows how wrong the advice was.

Please explain in detail what you did. What color wires to what, etc. At the splice did you have to add two junction boxes because there wasn't enough slack? Pictures of both junction boxes and at the receptacle may help us sort this out. http://www.doityourself.com/forum/li...-pictures.html Did that cable you cut run to a light?

 

Thank you so much for your response ray2047!

I am at work right now so I can't take any pictures, but here is my best description...

I did use two junction boxes because there wasn't enough slack in the original cable. So the first covered junction box I used to give myself more wire. I attached white to white, black to black and ground to ground using wire nuts. All I really did here was extend the existing wire by adding a patch of new wire from the junction box.

In the second junction box that I used to add my newly wired receptacle, I have 3 separate (Two 12/2 and one 14/2) wires. (I used 12/2 to wire my new receptacle and to give myself more slack on the original wire which is why there are two 12/2 wires coming into junction box.) In this junction box, I connected all of the black wires (3) together, all of the white wires (3) together and all of the grounds (3) together using wire nuts.

Now that you mention it, the lights did not come on in the two bedrooms after I shut the breaker off. So that breaker was for the lights and outlets in the two bedrooms.

Let me know if you need more information!

 

I suspect either a switch loop was tapped or a switched hot.

Do you have a way to test for voltage?

 

I do and I have been doing so. In the original receptacles in the bedrooms, when all of the breakers are on, read right around 120v and the new receptacle for the TV reads 0v. When the breaker is off, they read 0v but the new receptacle for the TV reads around 120v.

You mention:
I think I understand what a switch loop is. It sounds like part of making a light and light switch work. What is a 'switched hot'? Is there any way to use this wire the way it is or does this mean I need to find a different wire that is specifically for outlets?

Now that I'm thinking about the switch loop possibility, I haven't tested the new receptacle for the TV while the lights were on in any of the bedrooms. That would certainly explain why it's not working.

However, I find it very odd that if I turn that breaker off, the new receptacle reads 120v... How does that second breaker that I mentioned in my original post come into play?

 

When you get home try it with the light switch on. Also with a multimeter with the light switches off measure between the black and white at the splice.

 

A open neutral might explain the voltage readings.

 

My thought exactly..............................

 

Thank you all for all of your help!!! It is greatly appreciated!

So last night, I tested the switch loop theory by turning on the lights in both bedrooms and I still didn't have power to the new receptacle. So I thought I'd try turning on the lights in the two bathrooms (which are controlled by a second breaker which I've mentioned before) and voila, I had 120v to the new receptacle by my TV!

So now that I've got that figured out, I have a few questions...

How does that second breaker play into this? How can two breakers send power through one wire? Is there any way I can still wire this using the splice I've already created or do I need to find a better wire to splice?

The reason I'm asking if there's still a way I can make this work is because there is an outlet about 10' to the right of the TV but I have vaulted ceilings so there isn't much space in the attic over where I actually mounted the TV to work and the wall the TV is mounted on is an outside wall so it is full of insulation...

Having said that, I'll take any advice anyone is willing to provide!

What is an open neutral? How would that provide power to the new receptacle?