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https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl DIY Forum >> Electrical Questions >> Help detect electric power lines in a wall https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl?num=1314977452 Message started by Mati on Sep 2^nd, 2011, 4:30pm

Title: Help detect electric power lines in a wall
Post by Mati on Sep 2^nd, 2011, 4:30pm

I want to find the route of electric conductors in a wall. The wall thickness is up yo 6", most of it is brick but there are also stretches of concrete. I assume that along most the route the depth of the conductors is less than 2". Can someone recommend on an instrument for finding the conductors? Thanks.

Title: Re: Help detect electric power lines in a wall
Post by Lectrician on Sep 2^nd, 2011, 6:04pm

Cables should be installed in 'safe zones', but this does not mean they are!

Safe zones being vertically above/below sockets/switches, horizontally left/right of sockets/switches, 150mm from corner of walls/ceiling.

You can get cheap detectors, but they are hit and miss.

More expensive "cats" can be hired, and look for either metalic objects, AC waveform, or an injected signal tone on dead cables.

Google ezi-cat.

Title: Re: Help detect electric power lines in a wall
Post by wozzy on Sep 2^nd, 2011, 6:57pm

My tester injects a waveform onto the conductors then traces it, it cost £450 so you may want to find a electrician with one then hire them rather than purchasing yourself. When cables buried below 50mm it near on mm perfect.

Title: Re: Help detect electric power lines in a wall
Post by CWatters on Sep 3^rd, 2011, 10:59am

I have a cheap cable finder/stud locator that I got from Focus. It's quite good at detecting the voltage from a powered cable but for anything else it can be a fiddle to adjust the sensitivity - you have to set it so that it's within a wisker of triggering but not actually (false) triggering. There is definitly a knack to this. Once you get used to this it's ok for the price but this difficulty might account for some bad reviews of similar cheap products. If it's just one job you want it for I'd try a cheap one from somewhere like Screwfix which will normally let you take something back if you can't get it to work.

Title: Re: Help detect electric power lines in a wall
Post by londonman on Sep 4^th, 2011, 9:45pm

Even the expensive ones can be crap. I had a Bosch and it told me the whole wall was live!