Voltage reading puzzle

[ste77]

I did ask the question and claims not to have touched anything else, other than the CU. Which also seems to be confirmed by what the occupants are telling me.

Take onboard murdochs advice and let us know how you get on.

 

[toast]

But I don't think the OP does though. lol

I do agree, I tend to only perform the r1+r2, confirm the switching, then IR it.
But as this is a special occasion, I shall on this occasion be performing additional tests on r1+rN and r2+rN. Before we start breaking parts of the circuit down.

 

[toast]

Take onboard murdochs advice and let us know how you get on.

Duly noted and will report back on my findings.

 

[gaz101]

Have you reconected the cpc at the db

 

[partypest]

Pain, pain & more pain. I had one of these the other day. Eventually traced it to a borrowed neutral AND a pinched cable. The frustrating thing about these faults is they can be so time consuming to find but the only way is to start from the beginning and test from point to point in my experience. A customer told me the other day that a guy from SSE spent three days testing in their house to find a neutral fault. Good luck mate.

 

[Octopus]

I do agree, I tend to only perform the r1+r2, confirm the switching, then IR it.
But as this is a special occasion, I shall on this occasion be performing additional tests on r1+rN and r2+rN. Before we start breaking parts of the circuit down.

Special occassion?? You have voltage readings that suggest a lost neutral or earth, so checking continuity of ALL cores from the board to the accessories is the only step to make, this time, and every time you come across these situations.

 

[toast]

Have you reconected the cpc at the db

No, I disconnected the circuit

 

[toast]

Special occassion??

As this fault is new to me, that is why I asked the original question, it's an historical fault, not something I have introduced and required some help on fault finding and diagnostic. Which I grateful that you have offered.

 

[toast]

Pain, pain & more pain. I had one of these the other day. Eventually traced it to a borrowed neutral AND a pinched cable. The frustrating thing about these faults is they can be so time consuming to find but the only way is to start from the beginning and test from point to point in my experience. A customer told me the other day that a guy from SSE spent three days testing in their house to find a neutral fault. Good luck mate.

Well hopefully experience will put me in a more informed position next time.

 

[toast]

You have voltage readings that suggest a lost neutral or earth, so checking continuity of ALL cores from the board to the accessories is the only step to make, this time, and every time you come across these situations.

As I stated in OP, if I test across switch live and neutral on a closed circuit I get 240V at all fittings, which would suggest that the neutral is present. Unless as mentioned the neutral is borrowed/shared or returning via they earth.
I am unsure what you mean be lost with regards to this.
But I am grateful for your input, is it possible that the fault has been introduced via damage between conductors of two differing circuits and therefore also testing for that,via IR tests across differing circuits.

 

[Engineer54]

Pain, pain & more pain. I had one of these the other day. Eventually traced it to a borrowed neutral AND a pinched cable. The frustrating thing about these faults is they can be so time consuming to find but the only way is to start from the beginning and test from point to point in my experience. A customer told me the other day that a guy from SSE spent three days testing in their house to find a neutral fault. Good luck mate.

A pain maybe, but for someone that's familiar with fault finding in a methodical manner, that understands the values being shown to him by his test equipment, can sort these sort of problems out pretty quickly, even double fault problems!! Alas the above only comes with experience, and there is no substitute for experience!!!

 

[partypest]

Engineer54 how very true.

 

[gaz101]

What readings do you get with the cpc conected

 

[toast]

What readings do you get with the cpc conected

I was wary of connecting the CPC, as there was a young family in the house and some accessories were metallic. Also I would have expected the RCCB to trip, if any leakage to earth. So a reading was not taken, I am waiting for response from the client with regards of continuing the work, so as yet I have not been back to the job.