For newbies ..... CU change

[Octopus]

Been doing a CU change today before moving on to some installation changes - what do you notice about the 2 following pictures?












The installation dates from circa 1966 and has had the same home owner since then. In the last 5 years the boiler has been changed and also the meter has been changed.


This is really aimed at the newbies!

 

[rsmck]

Not long bought a house built (and wired) in 1953.... any form of earth is also conspicuous by its absence in most places... the fuse box itself is earthed, and there's even an attempt at an equipotential bond to the water pipe.... none of the socket earths seem to find their way back to the fuse box or any other earth though - some of them just connect to pipes!

 

[steamboatwilly]

Not long bought a house built (and wired) in 1953.... any form of earth is also conspicuous by its absence in most places... the fuse box itself is earthed, and there's even an attempt at an equipotential bond to the water pipe.... none of the socket earths seem to find their way back to the fuse box or any other earth though - some of them just connect to pipes!

Ah, those were the days.....

 

[Octopus]

Isn't word of mouth a powerful advert...

So today I was doing another house in the same road....






All was going swimmingly until I tried a Ze and found that the clamp on the suppliers "shaft" wasn't offering an earth at all!

At least the homeowner has main bonding, equipotential bonding and RCD's now (rather too reliant on the gas and water mains for the time being)

2 phone calls later and now a 8-12 week wait for an assessment from the supplier!

Oh joy!

 

[Amp David]

8-12 week, blimey. Its now same day up here! Well it has been the last 2 times i have called for a bad earth

 

[SW1970]

If it is 8-12 weeks do you take any remedial action in the meantime (e.g. TT?)

 

[malcolmsanford]

I have to admit I have never known an emergency call out for an installation earth to not be the same day, but with the industry at the moment I don't doubt murdoch at all.

Well think you would have to do something, yes you could TT the system as temp, fir RCD upfront protection if it never had it, but who is going to pay for this, you, your client, the DNO. If the DNO have supplied you with a TN system then they have the responsibility to maintain that, and telling me it will be 7-8 weeks to sort it out would not be acceptable

 

[Octopus]

er yes, converted it to a TT (got a nice low Ze of 6.9 ohms on the new rod), would have done that if the delay had been less, and also the supplier has confirmed a date in about 3 weeks to come and look.

 

[SW1970]

er yes, converted it to a TT (got a nice low Ze of 6.9 ohms on the new rod), would have done that if the delay had been less, and also the supplier has confirmed a date in about 3 weeks to come and look.

So out of interest who pays for the TT effort, and if it's the client would you expect them to be able to claim that back from the DNO?

 

[Octopus]

So out of interest who pays for the TT effort, and if it's the client would you expect them to be able to claim that back from the DNO?

Before I start a CU change I always take time to explain to customers that additional work may be identified during the testing and commissioning. The customer is OK about it and as I had to run trunking for the water bonding the change to a wider trunk and larger holes in his house didn't take much extra effort, so that leaves the 10 meters of 10mm, the rod and my time to connect it!

I'll also charge him to remove it if the DNO does convert the house to TNCS, plus the additional time to retest the site when such a change has been made - again I've talked the client through these eventualities, plus I'll note it on an email too.