Lead Pipe earth

[ecasam]

Hi Guys. I went to a house today and Ze was 1.09. Previous electrical paperwork states it is a TT system. Yes I did say previous electrical paperwork, I was shocked as well.

Anyway on further investigation the bare earth strands disappear under the floor, to a small crawl space under the building (My favourite areas.........NOT). The so called earth connection is made to an old lead pipe poking out of a nice new concrete floor. Looks like the old water main.

Although reading is OK for a TT, surely the old lead pipe is not a good earth and a rod should have been put in. :|

Your views please:x:x

 

[androiduk2002]

In my eyes all be it a trainees eyes , At some point in the future this pipe could/will be changed, leads not a good idea IMHO,with modern methods its more than liable to be replaced with plastic bang goes your earth.

A plumber could think that it was just a bonding and was not the main earth.

Im sure someone with more knowledge will be able to quote rules and regs, and will be along very soon.

 

[mojorebel]

A metal gas or water pipe must not be used as an earth electrode. regulation 542.2.4 but an old water pipe could be used if precautions are taken against its removal reg 542.2.4

 

[sparky b]

When you say old do you mean no longer in service? Do you know who owns the pipe, is it the local water board or private?

 

[ecasam]

Yes I do mean old, not in service anymore. The pipe is redundant and poking through concrete floor. The homeowner knows nothing about this pipe; just it used to be the main water.

Thanks for responses :x :x

 

[kme]

In that case, if you`re getting Ra of <2ohms, I`d leave it be. Upgrade the cable to it, by all means, and ensure there is the correct label fitted - note the location on your cert., and job`s a good `un.

I`m assuming that 1.09 was your Ra; not Zs(DB)?

 

[sparky b]

i'd go with kme on that one

 

[ElectekAir]

But then for less than

 

[jl-heating]

i would knock a rod in, if it looks right it is right ..

 

[Manator]

You should also consider that the pipe may be redundant at that property but may still be connected to the old supply and feeding water to another property which has not had the lead replacement.

This would make the pipe a service pipe.

More qualified amongst you may correct me.

 

[ecasam]

Thanks for all replies

:x :x

There is concrete everywhere. How would you guys put in an earth rod? :|

 

[ElectekAir]

Thanks for all replies :x :x

There is concrete everywhere. How would you guys put in an earth rod? :|

Drill through the concrete then bang the rod in

 

[Evans Electric]

You are probably getting the best earth off that pipe , (or earth electrode ) I'd run a proper cable and make use of it TBH make sure you record it .

 

[batty]

I would run new cable to pipe and put a new rod in as well that way your covered both ways. You have a reasonable earth from pipe and if it is ever disconnected the rod will be your back up is it all RCD protected?

 

[kme]

IF the lead ever became disconnected from other properties; you`d still have "your" length of lead in the ground; even if they bothered to strip out the redundant stuff; so you`d still have a fairly substantial lump of lead pipe, in excellent contact with ground.

I wouldn`t bother with a rod; I`d just run EC to the lead pipe, and clamp on - it isn`t going to disappear without trace;

 

[Nicky Tesla]

if it is on your property the lead pipe belongs to you and not the water supply company, so they will not change it, only the property owner can unless the water com. ask your permission as part of an area upgrade.

 

[initforthemoney]

Im sorry but that just isnt good practice at all.

As per what Manator said, it could still be in use to other properties, which means it is still a service pipe, albeit not connected at this particular installation.

Do the right thing and do a proper job.

 

[sellers]

what work are you doing on the property? Personally I would change it, it shouldn't be like that in the first place.

The pipe may go to next door and be unused but still be bonded and you may be getting your good earth off their TNS, TNC-S or TT system via the bond. New Consumer unit gets installed next door, spark gets rid of the bond to the redundant pipe and your ZE may go very very high.

 

[ecasam]

Customer wanted garden sockets and power to a pond pump. I was not happy with his earth as it currently is. Told him he needs a proper earth rod etc. I also told him to give his supplier a ring as his main fuse is ancient, he may try and get PME.

The garden job on hold till he makes a decision.

Thanks for all your replies:x:x