TT earth rod to shed or non connected garage..advice please

[Simonslimline]

Yes forget the lightning rod bit it was just another thing on my mind, and yes i do bond the gas and water, When i did my electrical training (quite a few years ago now) i can remember someone asking about caravan points have to have its own earth rod and i asked why it couldnt have both earthing systems and he said about a fault from the TNCS system has the potential to go through the caravan and into the earth rod. Myself i think the more means of earthing a system getting the resistance down as low as possible has got to be a good thing.
Also a electrician i do alot of work with has just done the car charging point course that was an NICEIC one and he had said that all buildings not connected to the main house has GOT to have an earth rod for its earthing and must not use the pme earth, when the tutor was questioned about it by sparks on the course he said it seems a thing where older electricians use a rod while the newer trained ones do it wrong and use the TNCS house earth. Also regarding the water bond i have had people tell me if the water is in plastic pipe then you need to cut some copper into it so you can bond it, but it states in the OSG that if its plastic pipe then it dosent require bonding.

A test to verify if it is extraneous or not should be carried out to confirm if bonding is or is not required. Again GN8 explains this.

 

[telectrix]

as above. if incoming water is plastic, then no bonding required. any metal pipes should be tested to see id they are extraneous or not. IR test from suspect pipe to MET. if reading is >22kΩ, then it's NOT extraneous, and does not require bonding. forget any niceic made up figures.

 

[dogwind]

The NIC are reknowned for making up their own regulations mate. None of them have any basis in fact.
An example is the nonsense they came out with a couple of weeks ago that anything which tests out at greater than 6.6 K ohms did not need to be bonded.

I have never registered myself with NIC but i used to work for a company that was and after i saw the work and stuff that was going on i decided i never would do.
A customer i work for had some electrical work done that was very bad and she contacted the council building control and was told by them they havent got time to follow it up, and would only come out if she had been hurt or maybe a fire. just shows the whole part P thing is a farce.

 

[Engineer54]

Hmmmm, now i wonder how the DNO's manage to provide all those Protective Multiple Earths in PME and even the TNC-S installations?? And NO, TNC-S isn't the same as PME!!

TT earth (rods mats, tapes etc) can be mixed with ANY of the TN earth systems, (TN-S, TNC-S, PME). It is not recommended that TN systems are mixed!!

Ignore anything a NICEIC spokesman states without confirmation from a known trusted source (that you'd be better off seeking in the first place anyway) .... Oh and it is now acceptable to use a domestic PME supply for car charging points!!

 

[Engineer54]

as above. if incoming water is plastic, then no bonding required. any metal pipes should be tested to see id they are extraneous or not. IR test from suspect pipe to MET. if reading is >22kΩ, then it's NOT extraneous, and does not require bonding. forget any niceic made up figures.

Just because a service water or gas pipe enters a building in plastic doesn't mean that the rest of the internal metal pipework will not be extraneous. Depending on the construction method of the building (especially concrete framed c/w concrete floors and ceilings) as well as the installation of the pipework, these metal pipes can very easily pick up extraneous potentials from the buildings fabric. That's why you should always test and not assume anything, even when the incoming supply pipes are in plastic....

 

[HandySparks]

Just because a service water or gas pipe enters a building in plastic doesn't mean that the rest of the internal metal pipework will not be extraneous. Depending on the construction method of the building (especially concrete framed c/w concrete floors and ceilings) as well as the installation of the pipework, these metal pipes can very easily pick up extraneous potentials from the buildings fabric. That's why you should always test and not assume anything, even when the incoming supply pipes are in plastic....

Indeed, a building's metal pipwork may be extraneous, even if supplied via a plastic incoming pipe. This raises the question, at what point should it be bonded? The requirement to bond close to the point at which the supply enters the building would appear to be irrelevant, as that's not the point at which the external potential is being introduced. In fact it may be impossible to determine why the pipework is extraneous without disconnecting sections for testing.

I recon this happens quite frequently with, say, a plastic water supply and metal gas supply pipe. The water pipes may test as extraneous, but only because they're connected to ground via the boiler and gas pipe. In which case, I would say that only one main bond is required, where the gas pipe enters.

 

[dogwind]

Hmmmm, now i wonder how the DNO's manage to provide all those Protective Multiple Earths in PME and even the TNC-S installations?? And NO, TNC-S isn't the same as PME!!

TT earth (rods mats, tapes etc) can be mixed with ANY of the TN earth systems, (TN-S, TNC-S, PME). It is not recommended that TN systems are mixed!!

Ignore anything a NICEIC spokesman states without confirmation from a known trusted source (that you'd be better off seeking in the first place anyway) .... Oh and it is now acceptable to use a domestic PME supply for car charging points!!

Thanks for your reply, he only did the charging point course last week and thats when he was told must use an earth rod and not the house earth. Was also told you must inform the DNO of every point you put in so they can keep a check on their loadings.

 

[Engineer54]

Thanks for your reply, he only did the charging point course last week and thats when he was told must use an earth rod and not the house earth. Was also told you must inform the DNO of every point you put in so they can keep a check on their loadings.

They originally came out with all the scaremongering about using PME supplies, but as far as i know have backed down and now allow PME supply sources to be utilised....

I don't understand why the DNO need to be informed about a car charging point being installed at a domestic residence on the basis of loadings?? Do you need to inform them if you install a storage heater, or two?? NOPE!!!

Are they going to refuse or deny the homeowner the right to charge a battery driven car from his household supply now?? lol!!

 

[dogwind]

They originally came out with all the scaremongering about using PME supplies, but as far as i know have backed down and now allow PME supply sources to be utilised....

I don't understand why the DNO need to be informed about a car charging point being installed at a domestic residence on the basis of loadings?? Do you need to inform them if you install a storage heater, or two?? NOPE!!!

Are they going to refuse or deny the homeowner the right to charge a battery driven car from his household supply now?? lol!!

Yes we both said that same sort of thing about telling the DNO, maybe they are worried about loadings with the government trying to push charging points but your main house supply will only allow a maximum load anyway so i cant see the point.

 

[davesparks]

It doesn't matter how many charging points there are installed, they aren't going to add any load until you plug a car in to it.
Now how many people have got a battery powered car to plug in to one of these things?

And why do they need a special socket to charge it from?

 

[Guest77]

Regarding the lightning conductors its not something i have ever done myself but was told that you must never connect a TNCS and an earth rod (TT) earth together because if a fault develops on the supply side into the building it can use your PME system down along the earth rod for its fault path.

Would you like a ladder in there?

 

[Guest77]

Yes forget the lightning rod bit it was just another thing on my mind,.

Oh thank God for that, phew, okay we can now sit down and relax.

 

[trev]

Thanks for your reply, he only did the charging point course last week and thats when he was told must use an earth rod and not the house earth. Was also told you must inform the DNO of every point you put in so they can keep a check on their loadings.

Oh bugger! Yesterday I installed a few extra sockets for an old lady and 2 outside lights for a neighbour. Best get on to the DNO then to let them know about these potentially massive extra loads then.
Who's been telling you this load of old crap mate?

 

[Guest77]

Dogwind sounds about right, or bull****, either is correct for this thread lmao

 

[Silly Sausage]

Oh bugger! Yesterday I installed a few extra sockets for an old lady and 2 outside lights for a neighbour. Best get on to the DNO then to let them know about these potentially massive extra loads then.
Who's been telling you this load of old crap mate?

WORSE!
I'm going to report you to the NICEIC and The Council.

You're going down!!!