British StandardBS 7671"Requirements for Electrical Installations. IET Wiring Regulations", informally called in the electrical communityThe "Regs", is the national standard in theUnited Kingdomfor electrical installation and the safety ofelectrical wiringin domestic, commercial, industrial, and other buildings, also in special installations and locations, such as marinas or caravan parks and medical locations
In general, BS 7671 applies to circuits supplied at nominal voltages (Uo) up to and including 1000 volts AC or 1500 volts DC. The standard therefore covers the Extra Low Voltage (ELV) range (0-50V AC, 0-125V DC), and the Low Voltage (LV) range (50-1000V AC, 125-1500V DC). The frequencies covered for AC are 50 Hz, 60 Hz, and 400 Hz, used in the UK for houses, offices, and commerce. It did not become a recognizedBritish Standarduntil the publication of the 16th edition in 1992. The standard takes account of the technical substance of agreements reached inCENELEC.
The current version is BS 7671:2018 (the 18th Edition) issued in 2018 and came into effect from 1 January 2019.Amendment 1 to the 18th Edition was published in February 2020 but the only changes were to section 722 (Electric Vehicle Charging Installations). These changes came into immediate effect upon publication release, unlike previous amendments where 6 months elapsed before changes became compliant.BS 7671 is also used as a national standard byMauritius,St Lucia,Saint Vincent and the Grenadines,Sierra Leone,Singapore,Sri Lanka,Trinidad and Tobago,Uganda,Cyprus, and several other countries, which base their wiring regulations on
Lichfield (/ˈlɪtʃfiːld/) is a cathedral city and civil parish in Staffordshire, England. Lichfield is situated roughly 16 mi (26 km) north of Birmingham, 8.1 miles (13.0 km) from Rugeley, 9 miles (14 km) from Walsall, 7.9 miles (12.7 km) from Tamworth and 13 miles (21 km) from Burton Upon Trent. At the time of the 2011 Census the population was estimated at 32,219 and the wider Lichfield District at 100,700.
Notable for its three-spired medieval cathedral, Lichfield was the birthplace of Samuel Johnson, the writer of the first authoritative Dictionary of the English Language. The city's recorded history began when Chad of Mercia arrived to establish his Bishopric in 669 AD and the settlement grew as the ecclesiastical centre of Mercia. In 2009, the Staffordshire Hoard, the largest hoard of Anglo-Saxon gold and silver metalwork, was found 5.9 km (3.7 mi) south-west of Lichfield.
The development of the city was consolidated in the 12th century under Roger de Clinton, who fortified the Cathedral Close and also laid out the town with the ladder-shaped street pattern that survives to this day. Lichfield's heyday was in the 18th century, when it developed into a thriving coaching city. This was a period of great intellectual activity, the city being the home of many famous people including Samuel Johnson, David Garrick, Erasmus Darwin and Anna Seward, and prompted Johnson's remark that Lichfield was "a city of philosophers".
Today, the city still retains its old importance as an ecclesiastical centre, and its industrial and commercial development has been limited. The centre of the city has over 230 listed buildings (including many examples of Georgian architecture), and preserves much of its historic character.