how to determine if a cable powers sockets or lights

[crowley131]

Hi,

I'm looking at putting a double socket in my loft.

It LOOKS as though the cables coming up through the wall into the loft supply the bedroom sockets, but i want to be doubly sure!

Is there a device i can get to measure the current flowing through a cable without having to cut into the cable? The idea is that I flick the upstairs sockets fuse box, see the current drop on the device then know i am ok to cut the cable!

Thanks in advance

C

 

[EFLImpudence]

You could try one of these but don't rely on it for actual testing.

http://www.screwfix.com/p/philex-83...=Search-_-SearchRec-_-Area2&_requestid=147059

 

[PrenticeBoyofDerry]

A voltage pen/stick will detect if the cable has a voltage going through it or not but not the current. It's not a thing I would trust my life with though!

 

[JohnW2]

A voltage pen/stick will detect if the cable has a voltage going through it or not but not the current. It's not a thing I would trust my life with though!

Yes, that's obviously the problem. If such a detector gave a very positive indication of voltage which totally disappeared when the sockets circuit was de-energised (and re-appeared when the circuit was re-energised), that would represent strong circumstantial evidence that it was the right circuit - but, as you say, it would not be 100% guaranteed (not than many things in life are!). I know how I would probably proceed (if there were no other practical alternatives), as probably do you - but, given the theoretical uncertainties, I would not advise anyone else to cut the cable unless they had been able to positively trace and identify it with certainty.

Kind Regards, John