Checking a borrowed neutral

[loz]

changing a fuse board today, house wired in the 60s with the landing light on the ground floor lighting circuit.
Tested at 250v ins res between the neutral of the 1st floor lights and the neutral of the ground floor lights. Result was 0.04meg ohm. Flick switch for landing light and the reading jumps to >200meg ohm.

Am I right in my thinking that this is a borrowed neutral?
In my head I can see the test voltage going up the upstairs lighting neutral, through athe landing lamp, down the live through a lamp one the ground floor circuit then returning back down the ground floor neutral

 

[sparksburnout]

Sounds like something from Quadrophenia! How do you see these voltages? Must be a fantastic test aid....Sure plays a mean pinball......

 

[7029 dave]

On the 2 way ?, bridged live off down stairs, 2 core up to pick landing s/l. never the less that will have no impact on IR test.

 

[westward10]

Not uncommon my 1970s house was the same, line from downstairs circuit neutral from the first floor. With both neutrals out the IR should be clear. Needs a bit of rewiring.

 

[loz]

So what's the test method to prove a borrowed neutral? My tests prove that the neutral of the 1st floor isn't separate from the ground floor circuit, i.e the landing light has its live from the ground floor circuit and its neutral from the 1st floor circuit

 

[westward10]

If you get zero Meg with one neutral out and the other still connected but this clears with them both out this almost certainly means crossed neutrals.

 

[uksrevivor]

Would a Continuity test on the neutrals confirm the same ?

 

[loz]

I work for a medium sized company. Haven't done a massive amount of domestic work on older peopertys. Is a forum not for asking questions and learning, if not what is the point of a forum, we can't all know everything but we can all be willing to learn, do you never ask a question on something your not sure on @sparksburnout ?
Here is a quick drawing to explain my way of thinking as to why I'm getting the result I am with the switches closed.

View attachment 35388

 

[PEG]

Your the one changing the board dude, what does your training and experience suggest? You will obviously be a member of a scheme, to be legally allowed to undertake this work, have you asked them??

Legally allowed? there is no way,from the information he has given,to deduce whether or not any legal responsibility is allocated

 

[sparksburnout]

Well if you work for a medium sized company, do they have a supervisor who is qualified to assist you in this? You have a LEGAL responsibility to comply with the building regulations when you are doing a domestic CU change, despite PEG's comments. You clearly do not have much of a clue what you are doing as this is a very common problem when undertaking domestic CU changes, how is this work going to be notified to the LABC? You are not supposed to be asking questions and "learning" when some customer has paid out ££££ for the privilege of you changing their CU!! You are supposed to know how to do it before you start the job.

 

[sparksburnout]

Legally allowed? there is no way,from the information he has given,to deduce whether or not any legal responsibility is allocated

Yes there is, he has to be a member of a scheme, or of a company who is, in order to undertake work that has to be LEGALLY done in compliance with the building regulations. Doesn't sound like he is, to me??

 

[loz]

Yes there is, he has to be a member of a scheme, or of a company who is, in order to undertake work that has to be LEGALLY done in compliance with the building regulations. Doesn't sound like he is, to me??

This is where you are wrong, I however spend most of my time in factory's and served my time on large underground private networks, so if you could keep your incorrect assumptions to yourself that would be great

 

[Des 56]

Quote sparksburnout
Yes there is, he has to be a member of a scheme, or of a company who is, in order to undertake work that has to be LEGALLY done in compliance with the building regulations. Doesn't sound like he is, to me??



Since when has the work associated with domestic installation been restricted to scam membership ?

The legality is that certain works are notifiable,its entirely up to the installer how he decides to comply with building regs
Scam membership is in no way a requirement for that person and so it should remain so

By the way,membership of any of the clubs would guarantee sweet nothing when installation standards are being assessed,there is possibly higher standards outside of these schemes than there are inside

 

[sparksburnout]

This is where you are wrong, I however spend most of my time in factory's and served my time on large underground private networks, so if you could keep your incorrect assumptions to yourself that would be great

So who is going to be notifying this CU change to the LABC?

 

[sparksburnout]

Quote sparksburnout
Yes there is, he has to be a member of a scheme, or of a company who is, in order to undertake work that has to be LEGALLY done in compliance with the building regulations. Doesn't sound like he is, to me??



Since when has the work associated with domestic installation been restricted to scam membership ?

The legality is that certain works are notifiable,its entirely up to the installer how he decides to comply with building regs
Scam membership is in no way a requirement for that person and so it should remain so

By the way,membership of any of the clubs would guarantee sweet nothing when installation standards are being assessed,there is possibly higher standards outside of these schemes than there are inside

OK, if you are going to be pedantic, the LABC could have been asked to come out and check it. Do you think this is the case?