ze 1.9ohms

[daz1963]

just been to quote for a added socket. nice new 17th edition board, so thought all should be ok. quick check of efli gives me a zs of 2.2ish ohms.same on a few more sockets. so goes to main board and checks ze,which is 1.9 ohms. a tad to high for tn-s at 0.85. now if this was a tt system that would fine. as its a tn-s would you contact the dno to rectify it? or would you leave alone and add the socket as its rcd protected? i will ring the dno and see if i get anywhere with them which i doubt.just wandered what anyone else would do.now be honest:wink5:

 

[malcolmsanford]

Honest ..................................I would do the job as your RCD will offer you that additional protection, but the law is that if the DNO have supplied an earth they must maintain it.

What as to be taken into account there are a load of TN-S systems lurking about that were created by Sparks over the year themselves and the DNO never supplied them, which maybe the case here. Me I would be calling the DNO and tell them their earth as failed, regardless how it was created in the past.

 

[needasparks]

Agree, in theory your treating it as a TT so can go ahead if it ticks the boxes for the purposes of your work and then contact DNO

 

[Groucho Mace]

Silly question but did you check the main earth terminal on the incomer ? I've come across loose clamps before that have given me similar readings.

 

[GLENNSPARK]

i always check all terminations/joints etc......on a EICR today.....bonding conductors: loose joints...both of em......

 

[sjm]

Recently I reported a high reading on a TNCS system that I had done some minor works and a PIR on.
DNO (Western Power) came out and checked. Upshot is that my customer now faces more expense because I have to install earth rods because the DNO have refused to maintain a PME connection that they say was not installed by them in the first place.

What do you do? Damned if you do it right and damned if you don't.

 

[Octopus]

Recently I reported a high reading on a TNCS system that I had done some minor works and a PIR on.
DNO (Western Power) came out and checked. Upshot is that my customer now faces more expense because I have to install earth rods because the DNO have refused to maintain a PME connection that they say was not installed by them in the first place.

What do you do? Damned if you do it right and damned if you don't.

Getting the DNO involved is the right thing to do.

Yes the customer will be facing extra costs, but would they rather have an unsafe house??????????????????

I think not.

 

[Inteificio]

Seems simple to me
The house is currently unsafe.

If you report it to the DNO you either get it fixed for free, or you get paid to do some more work.

So chance of more money or leaving a property unsafe....

 

[mechelec]

Report it as dangerous installation to DNO they will be out in 4hours or less. I would not like to treat it as TT as suggested as if the earth has deteriorated now who is to say it wont fail open circuit next week and leave the place with no earth.
Get DNO out ASAP

 

[nickblake]

One question did you check with the bonds connected you may not have an earth at all and the reading you are getting is due to parallel earth paths , isolate supply disconnect main earth then test, reconnect earth and re energize

 

[Engineer54]

So while your wondering what to do, your customers is left with an unsafe earthing system!!!! You contact the DNO Imeadiately, ...End Of!!

 

[mike the sparky]

Had a similar problem, checked with DNO if PME was available and was told it wasn't, left as TT. Returned 6 months later for another problem & found PME on site. Re-checked with DNO, PME still not available. A new comsumer had been installed by a "bathroom company" and had been converted to PME without checking.

 

[jimmymac]

Hi mike, why would PME not be availible? Is there certain criteria that the installation has to meet?

 

[Engineer54]

Hi mike, why would PME not be availible? Is there certain criteria that the installation has to meet?

NO ....But the supply cable needs to meet a criteria ... Multiple Neutral Earthing points by the DNO.

 

[jimmymac]

Aahhhh, i see. cheers