Hi all,
I live in a very old house with some very interesting wiring....
Currently trying to figure out an issue with the lighting in the basement. Trying to install fancy wifi switches, but the switch tells me there is low voltage on the line. Tested it and sure enough, its fluctuating between 60 and 100v.
I traced the wire from the switch to a junction box.
There are 3 wires going into it.
1) wire from the switch
2) power supply wire
3) wire that leads to the basement lights (in series sadly)

Disconnected the power, tested that wire and it's a steady 120V

I've found guides on how to wire lights with power into switch and power into the lights but can someone please help with how I should wire it up with the power coming in inbetween the switch and lights??

Thanks!!

 

You have a switch loop. You do not have a neutral at the switch. This is the same setup as if the power comes into the light.
You need to find a device that does not require a neutral. Or you could change the cable to the switch location to a three wire cable from a two wire.