Looking for a place to wire a new fluorescent strip in my 1955 home, I uncovered a wall plate high on the wall. A photo is attached. There is an existing fluorescent strip in the room, but I don't know what the wire path is to it.

Description: Two black wires, connected. Two red wires, connected. Two white wires and one red wire, connected.

In the electrical outlets I have worked with in this house black is hot, white is neutral and red is switched. My understanding is that black + red = 220v.

So what can I conclude from these wires? Do they tell me that they are part of a switched system, perhaps a junction in between the switch and the existing light? Can they be used to install a new light?

Many thanks in advance.

~John

 

We can not really conclude anything. My guess is that is an extension of a three way switch circuit.
Is there a three way switch on the wall under that or in the room on the backside of that wall ?

 

John, welcome to the forums! White (neutral) wires should never be paired to other colored wires, unless the white wires are redesignated with tape or paint on the ends. The three red wires and one black and one white seem to be newer wires. Are there cables entering this box? If so, how many? Is the box fed via conduit?

 

If the two blacks, two whites and three reds are all of the wires in that box, and given that there is information printed on the insulation of the wires, it might help us if you told us which of the wires enter in which conduit.

 

Thank you all for the quick replies.
None of the wires are taped. There is no three-way switch in the vicinity. I cannot see definitively whether there is an outer conduit for any of the wires. Chandler is correct that two of the wires are older, the rest are newer.

There are three points of entry into this box.
Upper: The older black & white wires
Lower: Two red wires (Update: listed wrong originally)
Bottom: Black, White, Red

 

Are these wires in conduit or are they cables? Odd that the Lower Black Red has no white, nor any grounding wire.

 

Chandler, the bottom wires (Black/White/Red) come through a straight metal conduit.
The black and white coming from the upper rear appear to be in a flexible metal conduit.
Two red wires coming from the lower rear are loose, neither cable nor conduit.

 

Hack job. OK, since the new wiring goes down, is there any receptacles, or switches below this junction? Do you have outside lighting that would be affected if you separated the wiring? You have a picture of how it is currently connected, why not disconnect and cap all the wires and reenergize it to see where they go. If you have a multimeter, it would be good to check each wire for voltage. I have a feeling the older white and black will be energized while the others won't. Confirm that for us, please.

 

Thanks Chandler.

On this wall below the junction box are an outlet, a double light switch and an old thermostat. The light switch and thermostat are to the right of the box, which is the direction that the red wires go.

On the other side of this wall ("B" side) is another junction box at much the same vertical level as this junction box. One of the light switches on the "A" side turns on a recessed light in the ceiling on the "B" side.

I was hesitant to test with the multimeter because I don't know for sure that the box is grounded, though the metal conduit is a good sign. I'm picking up a no-contact voltage detector today.

I'll need to do the testing tomorrow morning as I need to go to work now, and when I get home my kid will be sleeping in this room.

 

If the reds are loose in the wall they need to be removed and replaced with a cable if they are needed. At that time the color code can be corrected.

This looks like it might be on the outside of a house. If so the receptacle will need to be a tamper and weather resistant GFI with a weatherproof in use cover.

 

This is an internal wall.

Anticipating that this will be of interest I just had a look at the junction box on the other side of the wall.

In this box there is a cable with white, black and bare. The white and black wires are each twisted to a red wire and capped with tape. The red wire that is tied to the black wire is marked with black tape.

 

I am thinking there may not be any conduit since the box is held in place with Madison clips.

 

That's the second box, on the other side of the wall.

Hack job, as Chandler said. If this wiring is needed, those two loose red wires need to be replaced with a 2-conductor cable with a ground, properly sized for the circuit, as PCboss said. Either Type NM-b oe Type MC, if your jurisdiction requires that.