Earth

[Wattsy]

Hi All,

Started some work on a garage conversion today (attached) moving some lights/sockets etc.

Ze to current earthing conductor 66ohms.

Must be TT (not sure where the rod is though) but the meter and head were changed in 2006 and it looks like its been given a PME connection because theres an earth block on the service head with nothing connected to it. Couldn't do a Ze because i couldn't get into the cu because the customer didn't want me to turn off the supply, but there was 230 between it and live.

My question is, if i do a Ze test to the terminal and get

0.35ohms can i just connect to it or do I have to get DNO permission?

AND

If i change the earthing do i have to do an EIC for the whole installation as i would with a CU change. Its a large house with a swimming pool and all sorts and that would be a hell of a lot of work for the piece of 16mm connecting the MET to the head?

Many thanks

 

[Risteard]

My question is, if i do a Ze test to the terminal and get

0.35ohms can i just connect to it

Absolutely not.

 

[Wattsy]

Ok

 

[Andy™]

DNO may have provided an earth terminal, but installation didnt use and and was kept as TT. phone them and ask what the earthing type is for the property. if they say TNS or TNCS, then you should be OK to use it providing it tests out OK.

but if everything is OK with the TT you have, them may be easier to keep it as TT

 

[Wattsy]

Thanks.

I dont like it when i cant see/find the rod which seems to be the case a lot of the time. headbang

If i was to change it to TNC-S what certification would be needed?The NIC inspector told me once that i needed to issue an EIC for the whole installation when i renewed an earth rod because of a high Ze so i guess it would be the same.

 

[Apache]

If it's PME there should be a sticker.

 

[la poste]

My question is, if i do a Ze test to the terminal and get

0.35ohms can i just connect to it?

Absolutely not.

Why not?

 

[muffin]

pme should have an earth wire going down every third pole if its abc cable

 

[Lurch]

Why not?

Because you don;t know if it is PME or not, it could just happen to be a conversion in progress or something else. Basically, if you don;t know what the earthing type is you can;t use an educated guess and stick with it.

 

[SLIPSHOD & SLAPDASH]

If it's PME there should be a sticker.

But 75% of the time there is not.

 

[NozSpark]

But 75% of the time there is not.

At least 75%, if not more!

 

[steptoe]

WTF is wrong with people these days.........?

 

[la poste]

WTF is wrong with people these days.........?

I don't know what's wrong with us.

Could you tell us what's wrong with us?

 

[gselectrical]

Seen as you cannot locate the earth rod, would it be easier to disconnect the old one and install a new one? If you did this you would not have to contact the DNO to find out whether supply is part of a PME system.

If its a large house as you mention, then chances are there is more than 1 DB. Sticking with the TT system would mean you would not have issues such as exporting the earth. ray

GS

 

[steptoe]

Seen as you cannot locate the earth rod, would it be easier to disconnect the old one and install a new one? If you did this you would not have to contact the DNO to find out whether supply is part of a PME system. If its a large house as you mention, then chances are there is more than 1 DB. Sticking with the TT system would mean you would not have issues such as exporting the earth. ray

GS

:Applaud

well said that man.

why oh why have we got an influx of people all wanting to change (probably) the best earthing system we have in the UK to one of dubious quality.?

keep it TT.

 

[initforthemoney]

Personally i would opt for a more reliable earth connection via PME.

 

[tom1]

Personally i would opt for a more reliable earth connection via PME.

personaly i would opt for the system thats in place provideing its working correctly, ; )unless someone is willing to pay to have it changed

 

[ADS]

Personally i would opt for a more reliable earth connection via PME.

Ha ha ha - Wait 'til Steptoe gets hold of you! :run :innocent

 

[steptoe]

Personally i would opt for a more reliable earth connection via PME.

and how is PME more reliable?

and how do you know PME is even available?

you are solely relying on someone else to provide you with a means of protection that they dont care about, and can withdraw at any time with no prior notice,

DNO are NOT obliged to provide an earth, that is the only reason you get TNCS at all,

it costs nothing,,,,, not because its any good, its simply free.

for anyone to even consider going from a TT system to a poor excuse of TNCS it would be of my opinion that they should seriously consider doing a lot more research into earthing systems in the UK.

 

[Chr!s]

Lets not forget tt is the most widely used earthing system in the world.

And theres reasons why