ring continuity

[foghorn]

having added a couple of sockets to a ring final circuit when doing end to end tests i have no cpc end to end any advice i have checked my new works and all cpc connections are good could well have already been existing fault any advice welcomed

 

[Guitarist]

Foghorn,
You don't say what it's wired in or how many sockets but you could always consider reducing the size of the protective device.

Forgive me if I've missed something here, but how will reducing the protective device help locate a cpc break?

 

[GLENNSPARK]

I'ts normally helpful to confirm continuity before making such a change

IR test n all...make sure its good for continued service.....

 

[Singer]

Forgive me if I've missed something here, but how will reducing the protective device help locate a cpc break?

It wont but if for example it's wired in 2.5/1.5, if the mcb is reduced from 32A to 20A continuity on the cpc is then not necessary as its a radial circuit.

 

[telectrix]

how can it be a radial circuit when the L and N are still an intact ring?

 

[Guitarist]

It could be a new "Hybrid" circuit, half ring, half radial. I can see the advert now...."Fault-finding getting you down?....Go Hybrid."

 

[telectrix]

like the toyota pricus?

 

[Richard Burns]

It is a radial circuit wired with two conductors in parallel and not following the same route!

 

[pencilpusher]

It wont but if for example it's wired in 2.5/1.5, if the mcb is reduced from 32A to 20A continuity on the cpc is then not necessary as its a radial circuit.

Hmm, how about finding the original problem and sorting it?

 

[telectrix]

parallel conductors not following the same route contravenes a reg. forgot which one. it's a bit like buses. they follow different routes, but they don't have conductors any more.

 

[Singer]

Hmm, how about finding the original problem and sorting it?

Yes that would be the ideal way forward. I was simply offering an alternative. Provided both legs are connected to the same circuit breaker, then the circuit as a whole is protected by a 20 amp device and so the continuity around the ring is not necessary so any break in no matter which conductor doesn't matter. You can call it whatever you like.

 

[telectrix]

can't see the point of a 20A breaker. the load carrying conductors are still continuous and capable of carrying 32+A

 

[Singer]

Yea but the point is with a healthy ring final circuit each socket is fed by 5mm - 2.5 from each leg which is matched by the cpc being 3mm(1.5mm from each leg). If the cpc is broken and the circuit is still protected by a 32A mcb then each socket is then fed by 5mm live conductors and a 1.5mm cpc - incapable of carrying the fault current.

 

[Octopus]

It always makes me chuckle when suggestions to split a "faulty" ring in into 2 radials to fix the problem - because to do this properly will me you need to find the fault - and then why not fix it!!

 

[mickys86]

Unbelievable.

 

[Knobhead]

You can call it whatever you like.

How about daft?