Light fixture wiring. (confused by voltages at junction box wires)

[b.mueggenborg]

I've got two black wires coming out of a junction box that I want to wire a light fixture to. One black wire has white tape on it. It always has voltage to ground so I think I can assume that's my 'L' or 'hot'. I've tried connecting these two wires to my light fixture wires (and the ground to the box itself), but I don't get any lights turning on. The attached picture shows the voltages I get when the controlling switch is in each position, does this look correct?

 

[Marvo]

The voltages in the left hand picture are impossible.

0V between the black and ground means the black is at the same voltage as ground.
0V between the black and white means the black is also at the same voltage as the white wire

So by deduction the black, the white and the ground are all at the same voltage.

The 120V between white and ground is contradicting the other figures.

There's something wrong and to be honest I'd strongly suggest you should get a sparky in for half an hour to help you out. Lighting wiring is the most confusing, there's no way of knowing for sure how a fitting would connect just by looking a the colours and the test results you're getting are not good.

 

[Timbo]

Looks like black is switched live, white is permanent live. No neutral.
You will need to pull a neutral in to make the light work.

 

[b.mueggenborg]

Thanks Timbo and Marvo for the replies. I appreciate you confirming I'm not going crazy. Here's a few quick follow ups/thoughts:

1. The voltages are correct in the picture. I quadruple checked everything because it didn't make sense to me (and I've done a lot of wiring for my job, although in a laboratory setting where you start and finish the job yourself).

2. The 'White' wire is actually a black wire, with white tape on it.

3. When I tried I assumed the lights wouldn't work since I never get a differential between the two wires in either switch state, but I know the previous homeowner had a light here so I went for it, but it didn't work obviously. The only thing I can think of is if they had one light fixture wire connected to the black (the one that actually switches on and off) and then the other wire connected to ground. However, then my ground would be live when the lights are on which sounds like a BAD idea.

4. You guys confirmed what I was thinking, which is the previous owners had no clue what they were doing and my house has screwy wiring. This isn't the first thing I've run across that makes no sense to me. For example, a switch I've changed out in the past seemed to be missing a neutral at the junction box also. Did old houses just not use a neutral?

5. Last thing I might check is just to make sure a neutral didn't migrate its way back out of that junction box somehow.

6. I plan on a kitchen remodel in a year or two so may just deal without a light over the sink until then. We plan on a complete remodel so we may need an electrician in then anyways.