Sub Fuse Box Wiring to BS7671

[Fleeting]

I suspect it is lashed into the live side of the downstairs consumer unit.

 

[Murdoch]

I suspect it is lashed into the live side of the downstairs consumer unit.

a photo with the covers off may help understand what’s going on

 

[o.karel]

a photo with the covers off may help understand what’s going on

a photo with the covers off may help understand what’s going on

Thank you. And thanks to everyone took part. I am grateful for your time and the issues you highlighted .

I will certainly look into all. I would like to think that with the wiring coming off the ground floor fuse box and Fused Switch installed as close as possible, we will be able to avoid SWA cable rewiring to meet BS7671.

Please let me know if my understanding is incorrect.

 

[SPECIAL LOCATION]

Hello all
Can anyone please let me know, if BS7671 clearly specifies the wiring requirements for sub fuse boxes?

Hi... welcome to the magical electrical forumbulator...

To expand a bit on this part of your question:-

BS7671 gives guidance how to design, install, test and certify that an electrical installation will be capable carrying the expected load currents,
and maximum fault currents for all circuits of an installation without endangering people, property or livestock.

It pretty much covers everything wiring related in a domestic dwelling from the electricity meter onward...

The types of cable, installation methods, and protective devices will be governed by various factors including external influences due to the environment they are installed in, the length of circuits and ensuring permissible volt-drop is not exceeded...

But BS7671 does not actually say you must use a specific cable for a particular application...
as very often there are multiple ways to achieve compliance with BS7671.
(some relate to cost, aesthetic appearance, diversity considerations, ring, radial and/or parallel conductors etc.. etc..)

BUT...
it does clearly state what type of certification should be used for different types of works:-

New circuits, Consumer Units, Re-wires etc... Will require an "Electrical Installation Certificate". (EIC)
Additions and alterations to an existing circuit..... A "Minor Works Certificate" can be used.. (MWC)
Inspecting and testing of an existing installation without doing any alteration work..... An "Electrical Installation Condition Report" will be issued giving an overall summary if an installation is satisfactory or unsatisfactory for continued use. (EICR)


If someone, (AKA a cowboy electrician), has issued an EICR for installing a new sub-main.... then personally I would not trust much they say, anymore than I would trust my sister-in-law's friend who is a hairdresser for any electrical advice!!!

 

[Sharpend]

As suggested, a visit to ascertain the parameters of the installed cable and its source, supplying as many pictures as sensibly required will asssit greatly in confirming either way as to the compatability of the install.
too many unknown variables to give a sensible compliant answer...........

so over to you!

 

[o.karel]

Dear All who posted, advised on this question, just a quick update, the original electrical installer refused to run up and the builder brought in anther electrician, an additional fuse box was added adjacent to teh ground floor fusebox and appropriate installation certificate is issued after complete re- check of the entire installation.

I would like to say a big, huge thanks to all of you for your invaluable advice, information. Most appreciated. Keep your community going, great to see supporting each other and even me.