Knob & tube

[dhans]

Could someone please help me? I am changing some old knob & tube wiring and I have a couple of switches on the main floor that I want to upgrade the wiring for. Do I just have to send new wire to switch, then hook to existing wire in box or would the actual wiring to the light also have to be changed?

[kactuskid]

Need to know more information first. Does the power come into the light fixture box first and then a switch loop comes down from the light fixture box to the switch? Like the picture in this link:
http://www.estevancomp.ca/tesla/switchloopdiagram.htm

Is the Box you talk about making your connection in actually the light fixture box or some other box?

[dhans]

I have one wire going up to switch so I assume that the feed is coming into the light first

[dhans]

Connection will be made in switch box

[kactuskid]

You must have 2 wires at the switch box, not one. One wire connected to each screw right? This sounds like a switch loop like the picture on the link. If this is what you have then connect it up like the diagram. Make sure that you remark the white wire at both ends to indicate it is a hot wire and not a neutral wire.

To verify that this is what you have you can use a multimeter and measure continuity of the wires by twisting together the wires at the switch and then measuring across these two wires up in the light fixture. If you get continuity then you know this is a switch loop.

[dhans]

Yes there were 3 wires in switch box. One came down from light and 1 came up from basement and 1 linked the kitchen switch to the dining room switch. Thanks. Decided too much work...hooked back up the way it was.

[kactuskid]

What you describe is NOT a switch loop like the diagram above. What you have is power comes into the switch box first. Then a cable goes fromt the switch to the light to feed power to the light. The other cable going to the dining room light supplies unswitched power from the power feed comming into the switch box. It's just pigtailed.

So, if you want to replace the cable from the switch to the light you can do that no problem. But you'll need to write down how all the terminations are made and then make sure you connect it back up the same way.