Electrician in Hampton Hill, Hampton, Hampton Wick,Teddington, Fullwell, Twickenham, St Margarets, Richmond, East Sheen, Kingston, Chiswick and Sunbury AK Electrical © 2012

DESIGN

 

TESTING & INSPECTING

 

MAINTENANCE

 

NCE

INSTALLATIONS

REPLACEMENT  DISTRIBUTION  BOARDS  (DB’s)

 

A brief explanation of regulations and procedures:

 

Firstly the British standard wiring regulations BS7671 states (in no direct way!) that any electrician replacing an old DB is then responsible for every circuit re-energised. Therefore every circuit has to be fully tested and be deemed satisfactory to a minimal standard as well as basic earthing, primary fuses and supply characteristics.

 

This can either be done before the board is replaced or after. The latter approach is very risky for both client and electrician as any immediately dangerous condition found must be put right at someone's time and expense, or disconnected from supply.

 

If done before the best route is to have a Periodic Installation Report carried out to verify the condition of the entire installation before hand. This report is valid for up to 10 years providing no work is carried and can be used when selling the property, maintenance and to quote for or carry out any works including replacing DB's.

 

To give an example the tests and paperwork for a standard 3 bedroom semi with 1 bathroom takes 3-5 hrs+ depending on the condition of the installation, how well circuits are labelled and how much furniture is in situ.

 

When changing a DB it is also a legal requirement for domestic property owners to make sure the work is carried out by a qualified electrician who is also part p registered (domestic installer) so all works will be safe (done to BS 7671 standards), certified and registered with building control (this is done on behalf of the client by the contractor).

 

Once the DB is replaced and all circuits energised a 3 or 5 page Electrical Installation Certificate will be issued as per BS 7671, then the contractor has a period of time to register the works online where a Building Control Certificate will be issued and posted directly to the property owner.

 

With regards to the type of DB you have installed there are 2 basic types, either split load dual RCD boards where each RCD protects half the circuits in the property, this can cause nuisance tripping and not advised for multiple circuits or computer circuits.

The better and unfortunately more expensive DB’s have individual RCD protection of each circuit to cause minimal disruption and make fault finding quick and easy.