Hello!

A signal sent through a copper wire (DC) with between 20-50volts. If you wanted to monitor the signal/plot on a graph:

Can you do this without cutting the wire or attaching a device to the end of it? If yes:

Can you do this without cutting the insulation around the wire? I know that with technology these days you can detect wires behind walls using some electronic devices, but wondered if you could use similar devices to read and boost the signal (like wrapping a caliper around the insulation and getting some faint readings)?

What tools would you need? in either or both cases?

 

Sounds like a telephone line tap...

ak

 

Sounds like a telephone line tap...

ak

Yes kind of like that

 

I'd start by thinking about capacitive coupling, but that won't work for DC, except for a pulse when the DC first comes on or changes polarity. Same with winding it into a transformer core. You can pick up the AC components with the right equipment, but the DC will always be just pulse unless you can figure out how to use a Hall Effect sensor.

There's an idea! Try learning about Hall Effect sensors. They are now available for purchase.

 

A clip-on oscilloscope DC current probe should do what you want such as one of these.