supplies earth

[maguire]

Hi all.
what is the supply companys position regarding earth I have been told they will not supply an earth because the supply goes to a metal livestock barn and to make my own arrangments. The supply is by scottish hydro
mac

 

[GaryMo]

Seems pretty straight forward. Earth rod(s) and TT it is then.

 

[flameport]

They may supply an earth terminal for you to use, but they do not have to.

If not, you will have to make your own arrangements. You won't get an earth supplied where there are metal framed buildings.

 

[maguire]

cheers guys I have done a ZE on the part of the install that I am involved with and I get 104 ohms so that should be ok so do I have to root around in the field to find the spike ??

 

[Spark123]

Did you test the Ze in isolation?
It is always a good idea to know that the connection to the electrode is in good condition so is better to find it.
Also it isn't imo a good idea to have an electrode where livestock is wandering around owing to voltage pools and 4 legged animals

 

[maguire]

yes did that, I dont know what to do about the animals the guy keeps goats for cheese making and they are pretty self detemined creatures that think they own the place and they are kept in the big steel framed barn and I think that is bonded too. however, I am not to concerned about the livestock cos I aint afraid of no goats
Mac

 

[ban-all-sheds]

they are pretty self detemined creatures

I've always liked the attitude of goats.

they are kept in the big steel framed barn

Give them time - they'll eat their way out of that.

 

[dingbat]

... so do I have to root around in the field to find the spike ??

See page 127, reg 542.2.1, item (iv)

Maybe the foundations are being used as the earth electrode; far better than a rod any day.

 

[Stoday]

I used to keep a male goat:

I've always liked the attitude of goats.

BAS — our goat had much the same attitude. We got him as a kid, but when he matured he adopted some very bad and disgusting habits. The vet cured him with a snip...

 

[ban-all-sheds]

I used to keep a male goat:

Why?

Goats don't make good pets, and billies don't make good cheese....

when he matured he adopted some very bad and disgusting habits.

Was one of them, err.. splashing himself?

 

[ericmark]

Fig 705 page 187 details the earthing in a cattle shed which clearly states PE/PEN so does not have to be TT. However with those mesh plates I can see no way the ELI will be 104 ohms. I would expect less than 10 ohms and if more than 10 then I would consider it very unlikely that it followed the recommendations of 17th Edition.

However the distance required to test is likely to be extensive well over the standard reel of cable supplied with an earth tester and maybe you have not tested correctly.

I would expect you will need around 100 meters on each of the test cables to be able to test without the three test points showing very different readings.

If you are testing against the suppliers earth remember you need to subtract their reading from yours. Since they are allowed 21 ohms on their side then I would be looking for around the 30 ohm mark as a pass any lower and I would want to know why.

Although higher readings may pass one should consider the likely reading from such a large earth mat and the reading you give would make me think something is disconnected.