British Standard BS 7671:2008 defines high voltage as any voltage difference between conductors that is higher than 1000 VAC or 1500 V ripple-free DC, or any voltage difference between a conductor and Earth that is higher than 600 VAC or 900 V ripple-free DC.
BS 7671:2008 define an ELV device or circuit as one in which the electrical potential between conductor or electrical conductor and earth (ground) does not exceed 50 V AC or 120 V DC (ripple free).
The TDR sends a low-energy signal through the cable, returning within a known timescale generating a profile which can then be interpreted to pinpoint the fault location within the cable. A benefit of this method is that there is no breakdown of insulation.
This method sends a high voltage pulse down the faulted cable creating a loud noise at the location of the fault. The location can then be excavated, and a repair carried out. In some situations, this method can sometimes cause a small carefully monitored breakdown of insulation.
Classes of NEDeRS reports:
A ‘dangerous incident’ is one where the incident resulted in or could have resulted in a fatality or serious injury with an item of plant.
A notification of a company-specific suspension/change in some operational practice or procedure with an item of plant, for example; circuit breakers needing to be operated from a remote location or access restrictions around plant items.
A notification of a design defect or in-service problems/faults with plant items.
Currently there are four different connector types, however we can expect these to evolve in the future as VW Group and Porsche have already indicated that their new generation of vehicles will be able to charge at 350kW DC.
There are three main types of EV charging – rapid, fast, and slow. These represent the power outputs, and therefore charging speeds, available to charge an EV. Note that power is measured in kilowatts (kW).
Rapid chargers are one of two types – AC or DC [Alternating or Direct Current]. Current Rapid AC chargers are rated at 43 kW, while most Rapid DC units are at least 50 kW. Both will charge the majority of EVs to 80% in around 30-60 minutes (depending a battery capacity). Tesla Superchargers are also Rapid DC and charge at around 120 kW. Rapid AC devices use a tethered Type 2 connector, and Rapid DC chargers are fitted with a CCS, CHAdeMO or Tesla Type 2.
Fast chargers include those which provide power from 7 kW to 22 kW, which typically fully charge an EV in 3-4 hours. Common fast connectors are a tethered Type 1 or a Type 2 socket (via a connector cable supplied with the vehicle).
Slow units (up to 3 kW) are best used for overnight charging and usually take between 6 and 12 hours for a pure-EV, or 2-4 hours for a PHEV. EVs charge on slow devices using a cable which connects the vehicle to a 3-pin or Type 2 socket.
Corporate sustainability starts with a company’s value system and a principles-based approach to doing business. This means operating in ways that, at a minimum, meet fundamental responsibilities in the areas of human rights, labour, environment and anti-corruption. Responsible businesses enact the same values and principles wherever they have a presence, and know that good practices in one area do not offset harm in another. By incorporating the Ten Principles of the UN Global Compact into strategies, policies and procedures, and establishing a culture of integrity, companies are not only upholding their basic responsibilities to people and planet, but also setting the stage for long-term success.
National Electricity Registration Scheme (NERS). As part of an ongoing process to introduce competition to the electrical service market, we operate the National Electricity Registration Scheme (NERS) on behalf of the UK Distribution Network Operators (DNOs). NERS is managed and administered by Lloyds Accreditation.
Non-contestable work is work that can only be undertaken by the host Distribution Network Operator (DNO). For example the DNO is the only body permitted to determine the point of connection to the network.
Contestable work may be undertaken by a suitably accredited Independent Connections Provider (ICP). On completion the contestable works will then be adopted by the local DNO and integrated into their distribution network.
An Independent Distribution Network Operator (IDNO) is an accredited company with a wider scope than an ICP. After building a local electricity network, it will continue to own the local network and provide maintenance and 24-hour fault repairs.
Each of the 14 DNOs covers a separate geographical region of Great Britain. IDNOs own and operate smaller networks located within the areas covered by the DNOs. IDNO networks are mainly extensions to the DNO networks serving new housing and commercial developments.
These are the currently licensed IDNOs:
IDNOs are regulated in the same way as DNOs, except the IDNO licence does not have all the conditions of the DNO licence.
HSE and other organisations have produced guidance on electrical safety that is suitable for a wide range of industries and technical competencies. The information produced by HSE is either free for immediate download or available to order at low cost.
General electrical information
Information on accident statistics is also available from a number of sources.