High Ze

[M107]

So I've been out today to put in a new cooker circuit (i know Sunday working).

Anyway it's a Tns supply & I get a Ze reading of 23ohms (Zs on the cooker circuit 4.23ohms) so I call SSE for the customer & the conversation goes something like.....

Hi I'm doing electrical work at *******, the system is Tns & on testing Ze I'm getting a high 23ohms.

"where are you testing"

(trick question?) on the supply side of the cu main switch & all bonding removed.....why?

"well thats your problem your undertaking the test at the consumer unit, if you do the test on the spply side of the meter it will be ok, it normaly is when we send out an engineer"

Thats fine but your lot say I'm not legally allowed to open the meter connection, so unless that has changed or you give me verbal permission that I can record on my phone, you'll need to get somebody out to look.

"I cant give you permission............I've raised a job for you"

Thank you

"Our engineer will call when he is on his way, should be there with in 4 hours, can you isolate the installation?"

I can but I cant speak for what the customer does when I leave.

So rolling on 5 hours customer has just called me;

"the SSE bloke is here & he said it checks out ok, he is getting a 0.20ohms & said your meter might be uncalabrated."

Has he removed the (bonding) earth cables from the earth terminal next to the meter, & then tested like I did?

"No he has opened the bottom of the meter & put one lead on the black cable & another lead on the red cable & mumbled about DI's not knowing how to test ****. I dont have much faith in the bloke he is using a small meter like the sort you get at B&Q"

Why do we chuffing bother:C

 

[Andy™]

got to admit, ive never had any problems with NEDL when ive contacted them about a high Zs

 

[Sidewinder]

It beggars belief mate, if I did not realise it is the truth I probably would not believe it.

Meter Monkey!

 

[Evans Electric]

Theres never any common ground with DNOs .

Builder phones the other day , he,s at his sister's house ,the cut-out is getting very hot and theres a burning smell .

I tell him to switch off , phone EON (Central Networks) tell them their cut out is melting .

So they turn up , replace the cutout but don't re-fit the TN-S clamp on the lead sheath , saying the Ze is too high (29ohm I think) and to get an electrician in to sort it .

Builder says " But you fitted it last year " :Cheadbang

Doesn't matter we're not responsible for it , the network won't allow us TNS or TNCS . So my M8s going over to Rodney it .

 

[Sidewinder]

Breach in ESQCR I there I feel.

Once they provide an earth connection they are obliged to maintain it IIRC, too late to check & too busy tonight.

 

[flyingsparky]

Down here on the Surrey side of Gatwick we always get told that the DNO are not required to provide an earth connection and that if it's faulty or just plain carp we have to install an earth electrode etc etc. To be honest, sometimes the time spent trying to persuade them to come out is longer than just installing the rod and RCD. Just more expensive for the client, but at least it's safe when you leave.

 

[Sidewinder]

Throw ESQCR at them, but make sure you know the relevant sections and the surrounding statute law and the why's & wherefores.

 

[kerching]

quote

"No he has opened the bottom of the meter & put one lead on the black cable & another lead on the red cable & mumbled about DI's not knowing how to test ****. I dont have much faith in the bloke he is using a small meter like the sort you get at B&Q"

That could have been interesting on the hms setting [assuming that it was a B n Q multimeter, come to think of it why am I even writing this ....?]

Old meter bloke around here [back in the day] was the worlds leading expert on 'giving the tails a haircut' so he could get about 4 x 16s into one terminal............. :coat

 

[jameseye12]

"No he has opened the bottom of the meter & put one lead on the black cable & another lead on the red cable & mumbled about DI's not knowing how to test ****. I dont have much faith in the bloke he is using a small meter like the sort you get at B&Q"

Sounds like someone doesnt know how to do a Ze test.....

 

[M107]

I've got more work to do at this place (connect the new cooker circuit when kitchen is in & bathroom electrics on refurb) soon, so I expect I shall retest Ze and find it high, this time I'll wait for the bloke & test it for him.

 

[SteveT]

Breach in ESQCR I there I feel.Once they provide an earth connection they are obliged to maintain it IIRC, too late to check & too busy tonight.

absolutely correct - had same arguement two years ago with WPD, they wanted me to rod it!!! in the centre of town - 'shall I drive it through all this concrete?'

told WPD - your earth - you supplied - you are obliged to maintain...oh they did sort it

 

[NozSpark]

Unless it's a TNS PLC supply with a 951 clamp as the earth connection,,, in that case they deny all responsibility and say that it's a "DIY" earth:O