DNO Issue !!!!

[Ponty Massive]

Started a PIR for a customer to find the Ze was 58 ohms on a TN-S supply. Contacted the DNO who sent out one of their "Engineers." He confirmed my reading and then called for a jointing team.

The jointing turned up and said they had a reading of 0.3 ohms.

I went back to the property today to find again a reading of 58 ohms???

Called them up and again they sent another engineer around. I waited 2 hours but couldn't wait any longer. Finally had a call from the customer 3 hours later saying the DNO guy had turned up and could I speak to him on the phone? I explained my reading to the guy and he said he was getting a reading on 0.3....

He asked my how I was doing my test? It's a very old supply but I explained the incoming live to the suppliers fuse had exposed wire, I tested between this, neutral and earth. He then said his meter only had two leads and he could only test between live and neutral or live and earth but could not do all three???

Anyway, he excepted my reading of 58 ohms and said he would call his office.

20 mins later I had a call from the customer saying the DNO would PME the supply for a cost of £140+VAT.

Is this right? Surely it's their responsibility to provide a satisfactory earth??

Any help apprreciated !!!!

 

[trev]

As you know mate, if they supply an earth they have to maintain it but I reckon they'll try to wriggle out of this one even further than they have already, what's the betting on them saying your test gear is faulty or you're testing it wrongly

 

[telectrix]

why not try testing with your tester on 2 lead test. and has the DNO engineer tested with the main earth disconnected from the installation to eliminate parallel paths through th water and gas services?

 

[Specialist]

Their responsibility ? Yes but will you get them to sort it out without a wrangle ? doubtful, as trev said they'll probably come up with all sorts of excuses for why they're not responsible.

 

[Ponty Massive]

Infront of the customer I used my proving unit to confirm my meter was correct. I also tested with the gas and water connected and disconnected and it made very little difference. I was amazed the DNO only carry a two lead tester to begin with??

 

[Ponty Massive]

Their responsibility ? Yes but will you get them to sort it out without a wrangle ? doubtful, as trev said they'll probably come up with all sorts of excuses for why they're not responsible.

Surely it's their legal resposibilty. I've never come across this before where the DNO will not take resposibilty for their own earth supply. On other occasions I made a phone call, someone has been there within the hour and it has been sorted...But then having the cheek to try charging to correct the fault !!

 

[Engineer54]

I would fight it to the end, before i coughed up 140 pounds, for a situation they are responsible for. ...Another thing i would try and do, is to ask neighbours if i could test there Ze and see if they had similar values on there service heads.

Typical of a privatised company, try , try and try again to get out of there responsibilities, and get as much cash out of it as they can....

 

[Engineer54]

Surely it's their legal resposibilty. I've never come across this before where the DNO will not take resposibilty for their own earth supply. On other occasions I made a phone call, someone has been there within the hour and it has been sorted...But then having the cheek to try charging to correct the fault !!

But they are not even correcting the fault at all, ....just overcoming the fault!!

 

[Ponty Massive]

I'll be on the blower to them tomorrow. If they will not budge, who should my next call be too?

 

[Engineer54]

The ombudsman ...

 

[trev]

Rogue Traders?

 

[Ponty Massive]

Rogue Traders?

That would be great, Matt Allwright knocking on their door !!!! :63:

 

[Knobhead]

If the DNO have provided an earth in the past they have a responsibility to maintain it. It’s coved in the “sticky” DNO earthing arrangements I posted ages ago.

 

[mechelec]

As tony says if they provide an earth then they are under a legal obligation to maintain it. If they did not provide one or some cowboy has put an EC14 earth clamp around the paper lead incoming cable they will charge to supply a PME earth terminal.
OP why is it not ok for the DNO to use 2 wire testers??? When testing Ze they should remove the cutout fuse and customers earth and test L-N on concentric pvc supplies (PME, TN-C-S) and L-N and L-E on paper lead cables TN-S and (PME, TN-C-S). You do not need three wires to do this!

 

[dingledong]

i ad something like this ze high they sent an engineer around tested one double socket got an acceptable reading and left

 

[Engineer54]

What's testing a socket got to do with he's supply Ze?? All he would be seeing is Zs, that maybe acceptably low due to good earth paths from the Gas and Water bonds.

 

[telectrix]

i ad something like this ze high they sent an engineer around tested one double socket got an acceptable reading and left

that wasn't an engineer, that was a monkey. like measuring the titanic's funnel, then saying the ship was OK.

 

[Ponty Massive]

As tony says if they provide an earth then they are under a legal obligation to maintain it. If they did not provide one or some cowboy has put an EC14 earth clamp around the paper lead incoming cable they will charge to supply a PME earth terminal.
OP why is it not ok for the DNO to use 2 wire testers??? When testing Ze they should remove the cutout fuse and customers earth and test L-N on concentric pvc supplies (PME, TN-C-S) and L-N and L-E on paper lead cables TN-S and (PME, TN-C-S). You do not need three wires to do this!

I've been on the phone most of the day trying to sort this out. Seems the house was built circa 1955, the DNO have finally revealed the supply is a TT and when the original installation was done to the house, the domestic electrician who did the wiring, simply put a clamp on the armourings and used it as a TN-S supply, obviously no testing was done or has ever been done (dispite the fact they had a conservertory fitted about 10 years ago with sockets, lights and outside supplies).

DNO suggested putting a rod in or they would PME for around £140+vat.

What also amazes me is, theres a sticker showing a new digital meter was installed in 2008!!!!!

 

[mechelec]

DNO suggested putting a rod in or they would PME for around £140+vat.

What also amazes me is, theres a sticker showing a new digital meter was installed in 2008!!!!![/QUOTE]


People talk about DNO engineers being lets say less than thorough, well meter readers have in general less understanding of electricity than most
single cell amoeba. That may be a touch harsh but the amount of meter tails i have come accross that have just fallen out is quite shocking. FFS they only have about 4 connections to get tightened up correctly.

 

[mark1878]

Could someone explain how using a 3 wire tester would give a different result for Ze. I have a 3 wire tester but only use 3 wires when I dont want to trip the RCD, if I'm measuring Ze I just use 2 wires.

 

[stuart569]

Me also.I assume the readings would be the same?I think the 3 wire testers automatically display the higher reading of L-E L-N??

 

[Zeno]

Could someone explain how using a 3 wire tester would give a different result for Ze. I have a 3 wire tester but only use 3 wires when I don't want to trip the RCD, if I'm measuring Ze I just use 2 wires.

It is possible to get different readings by changing from a 2 wire to a 3 wire test on Ze or Zs.


Example from a real fault, (Megger 1552)
Tested a socket for Zs with plug, got a reading of 2.8ohm, tested another socket, 2.7ohm, maybe a broken ring or something? But continuity and readings OK on ring.

Go to another ring, high readings there as well.

Maybe Ze is high, so I did a two wire 20A bond test at the board, got a reading of .2ohm ish.

Strange I thought, get 2 wire Megger 345 no trip out, and do Z tests across the board all low readings?


Turn board off, do ohm test across MCB's check other circuits all OK?


Test across Neutral contact of double pole RCD and get 2 ohms ish FFS


Three wire testing uses the neutral as well.



Also on Hager RCDs and MCBs, always test for contact resistance they they burn easy, I have had around 5 cases of this.


Hope this helps.

 

[stuart569]

On a Ze you should be testing L-N anyway!Really? I have installed hundreds and hundreds of Hager boards and never had or heard of anyone having a burned out main switch or breaker.Had a couple dodgy rcd's and that's it!You must be buying fake stuff

 

[mogga]

ombusdman are sill to get back to me about S.P.s extorsionate charge for fitting an isolator as they dont cut and reseal any more only fit isolators at £150 ffs I told them Id pay no more than £50 as 1 hr and £15 for isolator but they have monopoly

 

[stuart569]

ahahahaha loving the sig mogga