Wire/Electricity detector

[konradIC13]

Hello,

I have idea to make a simple electric wire detector to find electricity wires in walls in my home.

I was thinking to control it with AVR ATmega8 (since i have it and i like doing stuff on them even if im beginner), doint all detect and signal stuff there.

For the sensor first thing that come to my mind is hall sensor. I just started looking up this topic on net and i found some various kinds of hall sensors (usually they have 3 pins), some are acting like switches, some of them will have voltage on output depending how strong is magnetic field.

Which one will be best to use? I want to detect electricity wires where there is current flow (since that will be easier and more accurate than making just metal detector or I am wrong?). Alternating current ~230V. Walls are max 30cm thick but wires should not be deeper than 5 cm into wall.

Maybe you know where to find similar project, so I can start with something already?

Im open for all suggestions, thank you.

 

[alec_t]

Unless the wire is carrying significant current or you can obtain a sensitive Hall device I think the magnetic field will be difficult to detect. Personally I would use a metal detector, because that will find wires whether or not they are carrying current; it will also locate metal pipes and studding so is more versatile.

 

[DerStrom8]

I built one that simply used an LM393 comparator and an antenna made out of an inductor. If a significant amount of current was induced in the inductor (caused by the electromagnetic waves emitted from AC wiring), the comparator would pick up the oscillations. The output was connected to an LED for a visual indicator, and to an earphone plug for audio indication of wiring. It was extremely simple. I think I might have the circuit around somewhere, if you're interested.

Of course, you could still use a microcontroller, but it seems rather overkill unless you want to do something special with the signal and output (different audio indications for 120v and 240v, etc).

 

[Sceadwian]

I'd make a metal detector as well, far more generally useful. You can however buy stud finders at many home improvement stores that have a built in feature to detect wiring. I believe they work by sensing the electric field.

 

[canadaelk]

The Tempo 200FP filter probe does just that, available used for less than $50 on ebay. Of course, that is not the same as nitting your own! E

 

[pilko]

Here's one for < $3.00.

https://www.ebay.ca/itm/LED-Light-A...274?pt=US_Battery_Testers&hash=item3f17a78d32

 

[Sceadwian]

pilko, those won't work through wall, you have to be much closer.

 

[pilko]

@ Sceadwian,--- It looks like the probe is insulated. I have a similar one with an uninsulated probe to which I attach a small loop antenna to increase the range.

 

[Dean Huster]

Stud finders go nuts when you run them over live wires and plumbing in a wall. Hence, they're not bad detectors.