Consumer unit
This term 'consumer unit' is now officially defined within the 2018 edition of BS 7671 (IET Wiring Regulations) as:
A particular type of distribution board comprising a type-tested co-ordinated assembly for the control and distribution of electrical energy, principally in domestic premises, incorporating manual means of double pole isolation on the incoming circuit(s) and an assembly of one or more fuses, circuit breakers, residual current operated devices or signalling and another control devices proven during the type-test of the assembly as suitable for such use. |
To many, the consumer unit is the modern-day equivalent of a ‘fuse box’ or ‘fuse board’ and provides the origin of all outgoing final circuits.
Successive evolutions of BS 7671 over the last few decades have seen the requirements for consumer units grow substantially – not only in what they may house, but also their construction – particularly in recent years with regards to increased fire safety.
The most recent version of BS 7671 in 2018 (the 18th Edition) now imposes much greater emphasis on ensuring that all such equipment that may be housed in such a consumer unit, often to fulfil specific individual purposes, is properly considered with respect to how it performs alongside other equipment in its vicinity. This will include attributes such as thermal performance, magnetic effects, fixing details and terminations, ability to withstand fault levels as well as current carrying capacity.
--ECA
NB Housing statistics and English Housing Survey, glossary, published by the Department for Levelling Up, Housing and Communities in 2019, states: ‘…in older systems, each individual electrical circuit was fed through an individual switch and fuse box. From 1960s through to the 1980s, fuses were collected together into a small number of smaller boxes, normally with a switch on the front which controlled all the circuits leading to the box. These boxes were normally fitted with a cover, the removal of which gave access to the fuses hidden inside. From the early 1980s, the newly named consumer unit (some dwellings have 2) catered for the whole dwelling and was also designed to accommodate modern safety measures namely circuit breakers and residual current devices.’
Related articles on Designing Buildings
- Articles about electricity.
- Circuit breaker.
- Consumer electronics.
- Domestic micro-generation.
- ECA articles.
- Electric motor.
- Electrical appliance.
- Electrical component.
- Electrical consumption.
- Electrical energy.
- Electrical installation.
- Electrical power.
- Electrician.
- Electrical safety.
- Electricity bill.
- Electricity supply.
- Flexible electrical networks for a low carbon future.
- Fuse.
- Glossary of electrical terms.
- Miniature circuit breaker.
- Panelboard.
- Radial circuit.
- Residual current device.
- The Future of Electricity in Domestic Buildings.
Featured articles and news
Editor's broadbrush view on forms of electrical heating in context.
The pace of heating change; BSRIA market intelligence
Electric Dreams, Boiler Realities.
New President of ECA announced
Ruth Devine MBE becomes the 112th President of the Electrical Contractors Association.
New CIAT Professional Standards Competency Framework
Supercedes the 2019 Professional Standards Framework from 1 May 2025.
Difficult Sites: Architecture Against the Odds
Free exhibition at the RIBA Architecture Gallery until 31 May.
PPN 021: Payment Spot Checks in Public Sub-Contracts
Published following consultation and influence from ECA.
Designing Buildings reaches 20,000 articles
We take a look back at some of the stranger contributions.
Lessons learned from other industries.
The Buildings of the Malting Industry. Book review.
Conserving places with climate resilience in mind.
Combating burnout.
The 5 elements of seiri, seiton, seiso, seiketsu and shitsuke.
Shading for housing, a design guide
A look back at embedding a new culture of shading.
The Architectural Technology Awards
The AT Awards 2025 are open for entries!
ECA Blueprint for Electrification
The 'mosaic of interconnected challenges' and how to deliver the UK’s Transition to Clean Power.
Grenfell Tower Principal Contractor Award notice
Tower repair and maintenance contractor announced as demolition contractor.
Comments
[edit] To make a comment about this article, click 'Add a comment' above. Separate your comments from any existing comments by inserting a horizontal line.