Earthing arrangements and the DNO

[daver]

Hi Guys.

Went to look at a job today. I am only doing CCTV, but the homeowner asked a question about his earthing, as he had removed the clamp from his water supply. Meaning no earth at all.
I took a picture of the arrangement, but with the exception of a small 4 / 6 mm cable which you can see at the bottom which runs behind the board to the CU and now re-connected to the water pipe in the kitchen, that is it.
There are no rods locally, the gas is not bonded, but can be done very easily. So i presume its TT.
Theres no 100ma RCD at the front end, and its on a very old wylex wired fuse board.
The worry is that he is putting in a new water supply in plastic.

Do the DNO have a responsibility for providing earth.
Will they put rods in for free
Or is it that he will have to pay to have it converted to PME, and what will this cost

Any guidance would be appreciated.

Regards

Dave

 

[diditrain]

Looks like a TNS to me.

 

[Deleted member 9648]

Hi Guys.

Went to look at a job today. I am only doing CCTV, but the homeowner asked a question about his earthing, as he had removed the clamp from his water supply. Meaning no earth at all.
I took a picture of the arrangement, but with the exception of a small 4 / 6 mm cable which you can see at the bottom which runs behind the board to the CU and now re-connected to the water pipe in the kitchen, that is it.
There are no rods locally, the gas is not bonded, but can be done very easily. So i presume its TT.
Theres no 100ma RCD at the front end, and its on a very old wylex wired fuse board.
The worry is that he is putting in a new water supply in plastic.

Do the DNO have a responsibility for providing earth.
Will they put rods in for free
Or is it that he will have to pay to have it converted to PME, and what will this cost

Any guidance would be appreciated.

Regards

DaveView attachment 8137

It is not permitted to use a water pipe as a means of earthing for obvious reasons....as above that looks like an earth onto the supply sheath,hence TNS.
Carry out a Ze test on that earth wire disconnected from the MET to be sure.

 

[Noton1205]

Get in touch with the dno as the cut out appears to be leaking pitch, when they come out they can confirm if you have pme available. If not they should put an new earth on the sheath.

 

[daver]

It is not permitted to use a water pipe as a means of earthing for obvious reasons....as above that looks like an earth onto the supply sheath,hence TNS.
Carry out a Ze test on that earth wire disconnected from the MET to be sure.

When i first looked, I thought it was TNS, but the earth wire which you can see at the bottom, is actually running behind the board and up to the CU, that is the one from the water intake. There is nothing connected to the sheath. There is no MET. Thanks anyway.

 

[telectrix]

are you sure the earth cable is not clamped/soldered to the cable sheath, under that tape? as wirepuller suggests, do a Ze test.

 

[richy3333]

If you are satisfied the earth wire goes behind and not into the cable sheath then it does look like TT, particularly with the up front RCD; otherwise as others have said TNS? DNO are not required to provide earth, but if they do they have to maintain it. Is the property in a location where you would suspect a TT system? Its worth asking the DNO if the earthing can be changed if the customer wants it and you think it worthwhile?

BTW why is the meter and cut-out in a Tupperware box ?

 

[telectrix]

seen these boxes before. in outside meter boxes. to prevent meter tampering.

 

[daver]

Absolutely positive it is not connected to the sheath. I am back there on Friday and will prove that point.
Richy, there is no upfront RCD which I would have expected with TT, sorry for confusion.
This is an old victorian house on a very busy street in Southport, so I would have expected TNS. He has only just bought the house, but it has been rewired in the last 15 years.
My only train of thought, is that it has been pulled out, but the pitch at the top is smooth as a baby's bum, no signs of a hole. No signs of clamp marks.

I may also suspect the plumber, that has put in that new 22mm gas, but theres no sign of another green cable.

I didnt have a lot of time yesterday, so the easy option was to take a photo. But for certain the earth wire at the bottom, goes behind the board and up to the CU.

And yes, the Tuppaware boxes are a common sight in Liverpool. Its to stop the tampering.

Thanks Everyone, will come back to you tomorrow.

 

[daver]

Well, in response.

Called Manweb out this morning and told them that the pitch was leaking. Had the coffee, cakes and smokes ready just in case.

He checked it over and all ok, and we asked about the earthing.
"Yes mate, we dont provide that and a lot of the houses round here dont have it." was his reply.
What are the options then?
Well Mate, call the office and we can come and sweat a wire on for you and provide a MET. But that will cost you about £120.
What about a coffee, some cakes and a smoke. And well give you £50 cash.
Dont carry any gear to do it mate, but your other option would be an Earth Rod. But that will be funny as all the house round here are built on sand.

So in conclussion, Manweb wouldnt help.

Not my problem, but thanks for all your help.

Cheers

 

[Engineer54]

There basically holding there own customs up for ransom then!! If they have an earthing system readily available, then they should by rights provide that earthing system to the customer. Even more so, when they know that a TT system isn't really an option because of ground conditions.

Time to go out and buy a couple of constant pressure spring clamps with a suitably sized earthing braid and amalgamating tape and provide that cable sheath earthing point yourself!!!

 

[Knobhead]

Anyone would think you and I were on commission for CP springs

 

[Engineer54]

Anyone would think you and I were on commission for CP springs

Well, at least we know they work and aren't going to cause any damage to the cable!!

 

[chiplard]

And if I was you I would get the plumber back round to move that pipe he has sneaked in behind the incoming supply! :13:

 

[daver]

Just out of interest, where would one purchase constant pressure spring clamps from?

 

[Knobhead]

Have a look at http://solutions.3m.co.uk/pv_obj_cache/pv_obj_id_BC01426B24AC69B79C7C1A40E588A4EAA7000700 your wholesaler should be able to get them.

 

[Paul.M]

Link doesn't work Tony.

As for these houses being built on sand, get a rod and do a Ra/Ze test to see the ground resistance.

 

[Knobhead]

Works for me

 

[Paul.M]

Problems on my end (oh matron)

 

[JamesBrownLive]

He checked it over and all ok, and we asked about the earthing.
"Yes mate, we dont provide that and a lot of the houses round here dont have it." was his reply.

I don't understand, I thought that they are required by LAW (ESQCR??) to provide an earth? How can they get away with this?