Low voltage
According to Approved Document P - Electrical safety – Dwellings: Low voltage is, ‘a voltage exceeding extra-low voltage, but not exceeding 1,000 V ac or 1,500 V dc between conductors, or 600 V ac or 900 V dc between conductors and earth.’ Where extra-low voltage is, ‘A voltage not exceeding 50 V ac or 120 V ripple-free dc, whether between conductors or to earth.’
The Illustrated Guide to Electrical Building Services, Third Edition (BG 31/2017), by David Bleicher & Peter Tse, published by BSRIA in 2014, suggests that: ‘Low voltage is a term used to describe 400 V three-phase and 230 V single-phase supplies. These are nominal voltages - the actual voltage may vary up to 10%. The intake to buildings that have a low voltage supply is usually provided by the electricity supplier in the form of an underground cable that emerges at a suitable point within the building. The cable is connected directly to the electricity supplier’s cut-out. Also known as a service head, this is a fused unit that protects the supplier’s infrastructure.’
[edit] Related articles on Designing Buildings Wiki
Featured articles
Check out some of the best features and news from Designing Buildings as well as key stories from around the web.
Your views needed - a strategy for the professions, trades and occupations.
Confronting competency, codes, capacity and costs.
The hidden risk in modern construction supply chains.
Construction Management, 10 June
24 months to 14: CITB launches accelerated apprenticeships.
Bridging the gap between clients and contractors
Concerns remain around contractor quality, capability, and delivery.
Construction Management, 10 June.
Heat pumps beat boilers in new home tests.
Building Safety Act implementation in Wales
CIAT to host industry panel on 26 June.
New and updated CLC building safety guidance.
New UK National Buildings Database.
Building Safety Wiki Interviews
Chief executive of the British Woodworking Federation.
Planning condition discharge in England and Wales
A brief explanation from a building compliance expert, with further links.