What exactly can an 'domestic installer' do?

[steptoe]

craig, that is fine, we all have to learn somewhere, but unlike dan, please do not state a fact, then change it as to beong an opinion, that is when we all get mixed up and lost, and when advice given is all wrong, I fo one cannot give advice on a maybe, if, or my drunken mate told me, unless your deunk mate told younhis sister fancied me, then thats fine,.

 

[steptoe]

on reading that,

do I look drunk?

lol

 

[Apache]

on reading that,do I look drunk?

lol

yes

 

[SPECIAL LOCATION]

craig, that is fine, we all have to learn somewhere, but unlike dan, please do not state a fact, then change it as to beong an opinion, that is when we all get mixed up and lost, and when advice given is all wrong, I fo one cannot give advice on a maybe, if, or my drunken mate told me, unless your deunk mate told younhis sister fancied me, then thats fine,.

my sister fancies you!Blushing:O

but then I have had a fewGuiness DrinkGuiness DrinkGuiness DrinkGuiness Drink

so I may be wrong??:|Pray] :^O :^O:^O

 

[dan.]

steps. I seem to annoy you, i would never claim to know it all i have a lot to learn. My post about a spark not bonding a lead pipe was to high light the need for the water to be bonded as it was metal and sticking out of the ground not that he should have stuck a clamp on the lead.if it was a plastic incomer then it would be different. As for the post about the rewire i would have checked the ze before starting and called the dno to find the problem. But then i dont do rewires.

 

[jl-heating]

spose thats just the same as seeing a CORGI/GASSAFE van all stickered up and thinking ahhh just the man. ?:| :|

yes just the same m8, there is a small difference with gas safe and corgi you should have ur number by the sign.

the number generally gives u a good idea how long the company/engineer has been trading.

ie: this year would be something like 3254008

20 years ago would be something like this 154008

when i look on ebay all the plumbers advertising 1000 pound combi installs are well into there 30`s showing me they are 6 month plumbers and working for beer money.

they have neither the experience or the brains to charge correctly for the work to be done.

 

[sparkyrj]

steps. I seem to annoy you, i would never claim to know it all i have a lot to learn. My post about a spark not bonding a lead pipe was to high light the need for the water to be bonded as it was metal and sticking out of the ground not that he should have stuck a clamp on the lead.if it was a plastic incomer then it would be different. As for the post about the rewire i would have checked the ze before starting and called the dno to find the problem. But then i dont do rewires.

The bonding should be carried out on the consumers side of the main stop c*ck regardless of what material the supply pipe is made of. surely the lead pipe already has a good connection to earth through the mass of the earth.

 

[dan.]

so will there be no potential difference between the non bonded metal water pipe should a fault occur?

 

[jl-heating]

i never thought of the errors of bonding to lead.

i would probably bond as close as possible to the stop tap were there is copper under the lead so as not to crush it, as we all know lead does tend to creep with the weight of it.

also look how the lead is clipped to the wall usually with iron bent nails or clips and they are generally ok if close together to hold the weight so i would wager its ok to bond on the lead.

 

[Andy™]

so will there be no potential difference between the non bonded metal water pipe should a fault occur?

your completely missing the point. the lead pipe can introduce a potential, BUT you cannot put a clamp onto a lead pipe, so if its all lead, you cannot bond it, and then recommend that customer gets a plumber to replace pipework with something other than lead

 

[dan.]

but ive already stated that the house is piped in copper . Yet it still wasnt bonded. Ah balls to it i give up. You experienced sparks obviously aint gonna listen to a lowly DI.

 

[steptoe]

but ive already stated that the house is piped in copper . Yet it still wasnt bonded. Ah balls to it i give up. You experienced sparks obviously aint gonna listen to a lowly DI.

dan in your original post you said the water was in lead,

then you changed it to say it was in copper.

the bit before the stopcock is of absolutley NO relevance to us whatsoever so has no bearing on what it is made out of, so when you said it was lead then I would think 99% of sparks would regard that as being the internal pipework.

and AFAIK it is actually ILLEGAL to bond lead pipework. something to do with a reaction to the metal as well as possibility of crushing.

 

[Andy™]

dan in your original post you said the water was in lead,then you changed it to say it was in copper.

the bit before the stopcock is of absolutley NO relevance to us whatsoever so has no bearing on what it is made out of, so when you said it was lead then I would think 99% of sparks would regard that as being the internal pipework.

and AFAIK it is actually ILLEGAL to bond lead pipework. something to do with a reaction to the metal as well as possibility of crushing.

Agree with everything you said there steps

 

[Jono Pashley]

Mine in Red

Questions.

You have just rewired a house with earthing arrangements set out as PME.

On completion you find that when tested the Ze is 0.46.

What do you now do?

Recheck all connections on consumer side,Check main earth CSA and length of run Check with DNO that the supply is actually a TN-C-S install

What reasons could be given for such a reading?

Fault on distributors side, Undersized Main Earth, Loose connection, (Main Bonding not disconnected?) Wrong earthing arrangment

What fundamental mistake did you do when you started the rewire?

Not verifying Ze prior to decommissioning the old CU/Verify its not a botched DIY PME/Request the earthing type from DNO

The questions would imply there is a fault, but I would like to know where the fault occurred and why.

So im still in my first year of college with very little practical experience as of yet, so dont kill me if im totally wrong. Please PM me the correct answer if you dont want to post it here as id like to know.

Cheers Jono

 

[jl-heating]

check the batteries on ur tester, flat batteries give stupid results.

 

[sarni31]

Ze should have been checked on initial visit. If DNO confirm as correct then thats what you have to work with.

If all curcuits are 30ma rcd protected a max zs of 1667ohms is allowed

Guiness Drink

 

[green-hornet]

Ze should have been checked on initial visit. If DNO confirm as correct then thats what you have to work with. If all curcuits are 30ma rcd protected a max zs of 1667ohms is allowed

Guiness Drink

Maximum Ze for a pme is 0.35

You cannot work with a Ze which is outside the given maximum values.

You must verify with the DNO that you have found such a fault they will have to investigate.

A 30 mA rcd on a TT would give a maximum allowed Zs of 1667 ohms but that is not what was asked and not the earthing arrangements for this situation.

You are correct that the earthing arrangements and the verification of an earth should have been carried out before any work is carried out.

However why or what reasons could you find for such a high reading on a pme supply?

 

[sarni31]

to be honest I'm stumped

10ohm difference ...but on a tn c s all controlled by the DNO so go on give us a clue ?????

 

[steptoe]

Maximum Ze for a pme is 0.35You cannot work with a Ze which is outside the given maximum values.

You must verify with the DNO that you have found such a fault they will have to investigate.

A 30 mA rcd on a TT would give a maximum allowed Zs of 1667 ohms but that is not what was asked and not the earthing arrangements for this situation.

You are correct that the earthing arrangements and the verification of an earth should have been carried out before any work is carried out.

However why or what reasons could you find for such a high reading on a pme supply?

sorry GH, but I think that is wrong,

that is what all the calcs given in 7671 are based on,

but I think its down to the DNO to verify what they will actually give you.

I have found that in most cases they will simply disconnect and tell you they are no longer supplying the earth if it is too high.

 

[sarni31]

sorry GH, but I think that is wrong,that is what all the calcs given in 7671 are based on,

but I think its down to the DNO to verify what they will actually give you.

I have found that in most cases they will simply disconnect and tell you they are no longer supplying the earth if it is too high.

Does that mean Im right Mr Steptoe ? ?:|