TT Eathing system to be installed

Garyburger · Apr 7, 2022

Will a TT earthing system be complicated to fit to a block of 6 flats and 1 communal area
And is it expensive
UKPN have told me this is there preferred option rather than a new supply from the road which would be very expensive

suffolkspark · Apr 7, 2022

Garyburger said:
Will a TT earthing system be complicated to fit to a block of 6 flats and 1 communal area
And is it expensive
UKPN have told me this is there preferred option rather than a new supply from the road which would be very expensive

Gary, I read in one of your other posts it is currently TN-S but another you said there is no earth .... which is it?

Taylortwocities · Apr 7, 2022

Complicated, probably not.
Cost, impossible to calculate remotely. You need a registered electrician who is experienced in TT systems.
NOTE that changing from the current supply type to TT will have implications on the installations in the 6 flats and common area.
We’re recent EICRs carried out on all flats? If so, hopefully there won’t be major changes needed, but only your electrician can tell you that.

James · Apr 7, 2022

I think you need to employ the service of an electrician to visit and provide you with options that are suitable for the building.
with a TT earth, the local distribution boards for each flat may have to be upgraded to include rcd protection amongst other things.

timhoward · Apr 7, 2022

It’s simple conceptually, but it all depends on the local conditions.
Factors include
- The cable route between the main incomer and a suitable site for an electrode.

How the distribution is presently arranged regarding mechanical protection
how and where it’s best to add the required RCD protection.

You need some quotes - this isn’t an abstract question - it relates to a specific property and installation so we can’t really guess complexity or costs.

Taylortwocities · Apr 7, 2022

James said:
I think you need to employ the service of an electrician to visit and provide you with options that are suitable for the building.
with a TT earth, the local distribution boards for each flat may have to be upgraded to include rcd protection amongst other things.

Snap! Unfortunately, after a lot of work by us both, I see that @Garyburger has another thread running on the same subject.
Wasted my time.

Garyburger · Apr 7, 2022

suffolkspark said:
Gary, I read in one of your other posts it is currently TN-S but another you said there is no earth .... which is it?

TN-S earth is clamped onto copper services

James · Apr 7, 2022

Garyburger said:
TN-S earth is clamped onto copper services

I am struggling to understand what the problem is then.

suffolkspark · Apr 7, 2022

Garyburger said:
TN-S earth is clamped onto copper services

A bonded service isn't TN-S? Sounds like just main bonding, you need an electrician on this ASAP.

Some photos would really help. But you do need an electrician

Garyburger · Apr 7, 2022

suffolkspark said:
A bonded service isn't TN-S? Sounds like just main bonding, you need an electrician on this ASAP.

Some photos would really help. But you do need an electrician

These flats was built 50 years ago and it’s only come to light there is not a decent earth
My electric cert is 3 years old but it is only when UKPN done an earth test on the block it’s found it’s not adequate
I attach a small part of my test cert

Intoelectrics · Apr 7, 2022

Garyburger said:
Will a TT earthing system be complicated to fit to a block of 6 flats and 1 communal area
And is it expensive
UKPN have told me this is there preferred option rather than a new supply from the road which would be very expensive

This question cannot answered accurately in any detail over an internet forum. In order to answer your questions you need the advice of an electrician who can come an survey the site first-hand. (as already been advised)

suffolkspark · Apr 7, 2022

Garyburger said:
These flats was built 50 years ago and it’s only come to light there is not a decent earth
My electric cert is 3 years old but it is only when UKPN done an earth test on the block it’s found it’s not adequate
I attach a small part of my test cert

Yea thats not TN-S. Historically incoming metal services were at times used for an earth. But they've ticked the wrong box, that's not TNS. You need to honestly get off here and get some electricians in asap