Drilled through an electric cable

[conny]

Regarding detectors, I have a Bosch Truvo and when I was installing some shelving used it to check for cables/metal work. One wall seemed to be live cables going in various directions even though there is only one socket on it. After reading the instructions I discovered if this happens you should 'ground' the wall by placing your other hand on it. Did this and was able to trace the cable accurately.
On Friday my FIL moved back into his new build bungalow so I decided to test my meter out on his home. I drew a sketch of his lounge/diner and tested all over the walls marking on my sketch where the cables 'appeared' to run. The builder and the legal eagles, i.e. insurance/architect/project manager etc came to lunch and I had spoke to the builder before and asked if he could bring the drawings with all the service runs on them. He duly arrived with the drawings showing where all pipes/cables/drains etc where running. I checked my cable sketch against his plans and they were spot on.

So maybe those of you who have problems with detectors need to calibrate your units and maybe read the instructions thoroughly. I thought you just held it against the wall but you don't.

 

[JohnW2]

So maybe those of you who have problems with detectors need to calibrate your units and maybe read the instructions thoroughly. I thought you just held it against the wall but you don't.

There may well me some truth in that.

However, the problem with the sort of detectors we're talking about is that one is, in the final analysis, 'looking for a negative' - i.e. are drawing conclusions from the fact that the device gives no indication when put over a certain piece of wall. Sure, if the device is able to detect the 'expected' cables going to/from all the visible accessories, that gives a reasonable degree of reassurance (since no 'expected' cables will not have been located), but the fact that the device 'does nothing' on some other piece of wall can never provide total assurance that an 'unexpected' cable has not been missed.

I would think that the only foolproof methods are imaging ones, which use some technology (X-rays, 'radar', ultrasonics etc.) to show one exactly what is inside a wall - and no DIYer, and probably virtually no ordinary tradesmen, are going to have such kit.

Kind Regards, John

 

[EddieM]

Regarding detectors, I have a Bosch Truvo and when I was installing some shelving used it to check for cables/metal work. One wall seemed to be live cables going in various directions even though there is only one socket on it. After reading the instructions I discovered if this happens you should 'ground' the wall by placing your other hand on it. Did this and was able to trace the cable accurately.
On Friday my FIL moved back into his new build bungalow so I decided to test my meter out on his home. I drew a sketch of his lounge/diner and tested all over the walls marking on my sketch where the cables 'appeared' to run. The builder and the legal eagles, i.e. insurance/architect/project manager etc came to lunch and I had spoke to the builder before and asked if he could bring the drawings with all the service runs on them. He duly arrived with the drawings showing where all pipes/cables/drains etc where running. I checked my cable sketch against his plans and they were spot on.

So maybe those of you who have problems with detectors need to calibrate your units and maybe read the instructions thoroughly. I thought you just held it against the wall but you don't.

I can relate to this.. my (lets call it dubious DMF10) seemed to work when my other hand was placed on the wall, but i couldnt find that advice in the instructions, yep Bosh make a pentrating Radar detector but at over £700 its more than most people would pay ( and i have no idea how good it is)