Strange 3way and light situation

[mark32]

Stopped by a friend's old house after work to look at a light that had not worked in two years. After some brief and conflicting troubleshooting results at the 3way locations (Both dead end) I took the light down. To make a long story short I replaced the light fixture and it worked, however the 3ways were not hooked up correctly so I began testing them and while doing so I noticed that when the light is off I get voltage to neutral (Using an two prong extension cord) at the one 3way location, but when I hit the 3way again, thus turning the light on, my voltage to neutral disappears? I then placed my one tester lead into the hot prong of the cord and now I have voltage. It was getting late and I wanted to get home so I told him I'd come back next week and finish up. What would cause such a thing to happen?

 

[iaov]

If you look up three ways in old posts you will find some excellent drawings of some of the wierd ways there are to wire a three way. Might help.

 

[cadpoint]

...
conflicting troubleshooting results at the 3way locations (Both dead end) I took the light down. To make a long story short I replaced the light fixture and it worked, however the 3ways were not hooked up correctly so I began testing them and while doing so I noticed that when the light is off

I'm thinking Seperation...

I get voltage to neutral (Using an two prong extension cord) at the one 3way location, but when I hit the 3way again, thus turning the light on, my voltage to neutral disappears?

Frankly I would hope so...
Lights are usually on the front or rear of its circuit, you didn't qualify that!

I then placed my one tester lead into the hot prong of the cord and now I have voltage. It was getting late and I wanted to get home so I told him I'd come back next week and finish up. What would cause such a thing to happen?

It was Late...

 

[dwellselectric]

Old house notorious for junction boxes in the attic. Good luck!

 

[480sparky]

Sounds like a Carter or California 3-way. The hot & neutral are tied to the traveler terminals, and the commons go to the light.

 

[frizbeedog]

.....at the 3way locations (Both dead end)

Are you sure you're testing a neutral?

If both switches are "dead end," there should be no neutral in the switch box.

 

[mark32]

Thanks for the quick responses. Carter or California 3-way? I'll have to check into that. I should have poked around the light box a little more, there are a few cables in there, but it's that old crusty insulation and I just wanted to get home and have dinner, I was starving

"Old house notorious for junction boxes in the attic. Good luck!"
- I hate working in old houses -

"Are you sure you're testing a neutral?"
- I used an extension cord for that -

 

[480sparky]

..... Carter or California 3-way? ......

Here's an example, but it's got the two 3-ways between a house and detached garage. But the wiring is the same if it was in the same structure. Just ignore the receptacle and the two buildings.

Good luck tracing things out in an old house that got nothing but black wires.....

 

[frizbeedog]

Here's an example, but it's got the two 3-ways between a house and detached garage. But the wiring is the same if it was in the same structure. Just ignore the receptacle and the two buildings.

Good luck tracing things out in an old house that got nothing but black wires.....

Great graphic Ken.

That looks like it would explain the readings he's getting.

 

[mark32]

Oh my, I've never seen that before. I appreciate the functioning diagram 480, perhaps this is the so-called New Jersey 3-way I stumbled upon

 

[480sparky]

Oh my, I've never seen that before. I appreciate the functioning diagram 480, perhaps this is the so-called New Jersey 3-way I stumbled upon

It's got a lot of names.... Carter, California, Indiana, Farmer, Handyman, Hot-Wire, Back-Fed......