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
A case study and a warning to would-be developers
Creating four dwellings... after half a century of doing this job, why, oh why, is it so difficult?
Reform of the fire engineering profession
Fire Engineers Advisory Panel: Authoritative Statement, reactions and next steps.
Restoration and renewal of the Palace of Westminster
A complex project of cultural significance from full decant to EMI, opportunities and a potential a way forward.
Apprenticeships and the responsibility we share
Perspectives from the CIOB President as National Apprentice Week comes to a close.
The first line of defence against rain, wind and snow.
Building Safety recap January, 2026
What we missed at the end of last year, and at the start of this...
National Apprenticeship Week 2026, 9-15 Feb
Shining a light on the positive impacts for businesses, their apprentices and the wider economy alike.
Applications and benefits of acoustic flooring
From commercial to retail.
From solid to sprung and ribbed to raised.
Strengthening industry collaboration in Hong Kong
Hong Kong Institute of Construction and The Chartered Institute of Building sign Memorandum of Understanding.
A detailed description from the experts at Cornish Lime.
IHBC planning for growth with corporate plan development
Grow with the Institute by volunteering and CP25 consultation.
Connecting ambition and action for designers and specifiers.
Electrical skills gap deepens as apprenticeship starts fall despite surging demand says ECA.
Built environment bodies deepen joint action on EDI
B.E.Inclusive initiative agree next phase of joint equity, diversity and inclusion (EDI) action plan.
Recognising culture as key to sustainable economic growth
Creative UK Provocation paper: Culture as Growth Infrastructure.























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.