if you have any ideas for the next test, post them in the other thread
Today`s call out to an "impossible" scenario.
- Thread starter kme
- Start date
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As a first model then yes it would work, though you would have to iterate.
Unless you have a single supply from a single Tx, the supplies would almost certainly be a mix, and the earth paths would be "complex".
Unless you have a single supply from a single Tx, the supplies would almost certainly be a mix, and the earth paths would be "complex".
herein lies a massive problem with TNCS,
if your neighbour has a fault then you inherently import that fault,
especially if your neighbour happens to be smart enough to get himself a TT install, thereby you gain his fault to use as you so wish, and if your MEBs or supplementary bonding arent up to scratch then who knows what might happen.
why do i have a feeling ill be making a 'second' TNCS system, with an earth rod as an 'extraneous' pipe into the property, very close to my 'TT' system with a fault....
Given Chris` point; I`d be more concerned with the local neighbours` rod voltages, TBH......They could "see" some of that voltage, surely?
Andy - the earth within the property must have risen above the midpoint voltage of L & N; in order for the meter(s) to recognise reverse polarity; i.e. >120V
Andy - the earth within the property must have risen above the midpoint voltage of L & N; in order for the meter(s) to recognise reverse polarity; i.e. >120V
what rods?
I thought he said his house was TNCS, what are the realistic chances of there actually being a rod anywhere nearby?
sod them, if they get a dig then maybe they will upgrade their earthing system, :slap
may have a play with earth rod resistnce and get the point at which 'reverse polarity' occurs.
anything else you want tested?
Manator
©Honorary Essex Boy™
I could send some white coat men around to have you tested Andy !!!
Only joking, just make sure any test you carry out is controlled, and wear your gloves for my sake if not yours please.
Only joking, just make sure any test you carry out is controlled, and wear your gloves for my sake if not yours please.
its well controlled. even as far as a contactor with remote on/off button for the supply i use
Im not letting Manator anywhere near my 16mm jammed in a choc-block isolator I have for the house,,,,!!!!!!!!!
:slap
but I have some marigolds hanging beside it if you need to pull it out.!
:slap
but I have some marigolds hanging beside it if you need to pull it out.!
I actually BOUGHT some live working goves the other day!
I will confess to never having had them before, but I had an issue that I may have needed them to resolve & thought well they are not THAT expensive and they are 1kV and they could save my life!
I managed to do it dead in the end!
I will confess to never having had them before, but I had an issue that I may have needed them to resolve & thought well they are not THAT expensive and they are 1kV and they could save my life!
I managed to do it dead in the end!
Manator
©Honorary Essex Boy™
An electrician once laughed at me whilst I was doing a PIR on a factory wearing my gloves, I found a fault on a 3ph printing machine he was supposed to be in charge of, I taught him a quick lesson on the effects of rubber insulation against the effects of skin. He never did wear gloves thereafter but he never laughed when I did.
But did you get the testing pump??.
I have some, and a flash guard, must see if my apron is still in the shed too, though I have a feeling someone 'borrowed' it a while back.
Manator
©Honorary Essex Boy™
To be honest we all laugh about it, but we are all equally guilty of complacency, electricity kills and as we are front line we are more susceptible than most to the dangers. I once connected a full school annexe live, I had a lad working with me on standby who was more scared than I was because he knew how dangerous moving a live 35mm live cable mm away from the metal trunking was. After I connected the said supply I told him that if I ever caught him working live I would skin him alive and feed his eyeballs to the seagulls.
I still think he has not forgiven me for doing it, but I do know that he is the safest worker I have.
I still think he has not forgiven me for doing it, but I do know that he is the safest worker I have.
Been there Manator, I did something similar with an engineering workshop in a tennanted area of a building with no access to the main switch gear!
The "client" would come no where near me nor could he arrange for a supply disconnection!
I had to disconnect and remove from a metal clad isolator a TPN supply and refit to an "old" metal clad 3ph db we are back in the late 80's/early 90's now mind!
Boy did I sweat especially as we had no idea of what was at the other end, it was a weekend and the factory had to run on Monday a.m.
No possibility of contacting the landlord, nor isolating (last thought) if I had a belt.
However, as you can see (well read!) I am still here.
I would not say NEVER again, however, different precautions would be taken now!!!
The "client" would come no where near me nor could he arrange for a supply disconnection!
I had to disconnect and remove from a metal clad isolator a TPN supply and refit to an "old" metal clad 3ph db we are back in the late 80's/early 90's now mind!
Boy did I sweat especially as we had no idea of what was at the other end, it was a weekend and the factory had to run on Monday a.m.
No possibility of contacting the landlord, nor isolating (last thought) if I had a belt.
However, as you can see (well read!) I am still here.
I would not say NEVER again, however, different precautions would be taken now!!!
Manator
©Honorary Essex Boy™
I have gloves that I only use for PIR,s, I never ever work live now, if a client is not prepared to a temp disconnection I walk. The only reason I test with gloves is that as I know nothing about the installation I never take the risk that prodave took when he assumed that by isolation everything was dead.I have had my fair share of "belts" and do not want any more. I reached my age by being cautious.
