Diagram for finding a fault on a ring main

[nozspark]

Good pics RF, but then you were always the king of pictures..

 

[Softus]

The other way is.

if you cant find where it IS
then find where it ISN'T

so in the case of a ring you break it down and if its not in one half it must be in the other

That's exactly the same way as nozspark's.

 

[Slynxx]

Thanks guys - just to confirm, disconnect at CU ?
Then do an IR test on each disconnected socket until you get an abnormal reading.
From this, you can then ascertain which section of cable is faulty.

 

[nozspark]

yes

Disconnect at the CU then split the faulty circuit in two, test and then split the faulty side in two... carry on doing this until you cannot split it any more and have found the fault.

This method is called the 'half split method'

 

[Slynxx]

Nozspark (and others)
You're stars.
The penny has finally dropped.
Thank you very much.

 

[ricicle]

This method is called the 'half split method'

Or just logical fault finding.......

 

[DESL]

You need to have the "Knack"

http://www.youtube.com/watch?v=CmYDgncMhXw

 

[davelx]

This method is called the 'half split method'

Or just logical fault finding.......

or a "binary chop" to computer programmers

 

[ebee]

the other thing to bear in mind is that unless you installed the ring yourself it might not be that easy to work out the order that the sockets are wired in

 

[Softus]

That doesn't matter - the principle applies and works no matter what the order is or how many accessories are on the ring.

 

[ricicle]

The other way is.

if you cant find where it IS
then find where it ISN'T

so in the case of a ring you break it down and if its not in one half it must be in the other

That's exactly the same way as nozspark's.

I think Mr Breezer is/was an appliance engineer, not an experienced electrician, that'a why some of his replies are a bit vague....

 

[Murrreid]

I agree, it's not too easy when its an old installation and you don't know how it has been wired. You can't really find mid points, any tips ?

 

[plugwash]

Assuming your fault doesn't have all three cores shorted you could short one end to help you determine which sockets were on which side of the gap you opened.

 

[Softus]

I agree

With what?

it's not too easy when its an old installation and you don't know how it has been wired.

It is easy - you just follow the process already described.

You can't really find mid points, any tips ?

It doesn't matter - just keep breaking it down until you find the faulty segment.

 

[meb97me]

I realise this is a VERY VERY old post, but i found RFLighting's diagram(s) extremely useful as i'm about to have a look at our ring main as its recently developed a tripping fault however i have one quick question.

When you say Test each leg of the ring how eactly would you do that with a multimeter once you've broken the circuit? would you need some very long leads to connect the wires between the CU and the socket you are testing?

Could someone be so kind as to describe the steps for a dullard like myself, it's proabably very easy but the penny hasn't quite dropped for me yet

Cheers