IET logo
Decrease font size
Increase font size
Topic Title: I&T and Certifying a service alteration
Topic Summary:
Created On: 10 October 2012 09:01 PM
Status: Post and Reply
Linear : Threading : Single : Branch
Search Topic Search Topic
Topic Tools Topic Tools
View similar topics View similar topics
View topic in raw text format. Print this topic.
 10 October 2012 09:01 PM
User is offline View Users Profile Print this message


Posts: 118
Joined: 16 April 2009


Next week I shall be having the service head and meter relocated on my house which I have recently re-wired. - The original job has been certified and notified.

It will mean installing new tails, and providing a switch fuse to provide protection for the tails as they will exceed 3m.

In terms of testing and certifying this, am I correct in thinking that I will need to re-test all final circuits as well as the new distribution circuit, and issue an EIC with a full schedule of test results? - Obviously Ze and therefore circuits' Zs will almost certainly change, if only fractionally.

Also, in 'extent of installation covered by this report' what kind of thing should I be writing to make it clear that it's just the distribution to the CU that is being installed?

Thanks as ever,

 10 October 2012 09:21 PM
User is online View Users Profile Print this message


Posts: 858
Joined: 03 May 2006

Hi Dave , not sure if you would need to retest the whole installation.

The R1+ R2 for the circuits will still be the same and insulation resistance will be unaltered.

You will need to test the submain so I cannot see any reason why you cannot just add the additional R1 +R2 of the submain onto the circuits.

I would personally Zs test all sockets.

In the extent of installation box you could write " installation of new submain to consumer unit ".

 10 October 2012 09:40 PM
User is offline View Users Profile Print this message


Posts: 3676
Joined: 22 November 2007

If it's your own place so you know no one has "fiddled" since the last set of results. I'd do a cert for the sub-main and use the sub-main Zs as the starting point for a replacement cert for the house (if it's changed enough to worry about)

 11 October 2012 08:20 PM
User is offline View Users Profile Print this message


Posts: 118
Joined: 16 April 2009

Cheers guys,

I was hoping someone would suggest it wasn't neccessary to re-test the entire thing,

I think you're right, - as I did the original cert, I will be able to re-certify based on the original readings.


See Also:

FuseTalk Standard Edition v3.2 - © 1999-2016 FuseTalk Inc. All rights reserved.