EV Charging Terminology

Active Load Management (ALM) is a load control approach that monitors available electrical capacity and actively adjusts EV charging demand in response to changing site conditions. It may use live measurements, control rules or backend commands to reduce, increase or redistribute charger output.

BS 7671 is the UK national standard for electrical installations, covering the design, erection, inspection, testing and verification of low-voltage electrical systems. Section 722 contains specific requirements for supplies to electric vehicles.

Configurable current allows the maximum charging current to be set or limited during installation or configuration. It is normally assessed against site capacity, maximum demand, charger grouping and the behaviour expected when electrical demand changes.

Derating is the reduction of charger output or performance under certain conditions, such as high temperature, supply limits or component protection. It is normally assessed alongside phase availability, circuit capacity, protective devices, cable sizing and DNO/site constraints.

An earth electrode is a conductive part placed in the ground to provide an electrical connection to earth. It is normally assessed during product selection, circuit design, installation verification and maintenance of EV charging equipment.

EN 60364-7-722 is the European and international low-voltage installation standard for supplies to electric vehicles and related EV charging circuits. It formed the basis for EV charging installation requirements that have been incorporated into the UK through BS 7671 Section 722.

ENA EREC G94 is a UK Engineering Recommendation addressing the risks and arrangements associated with multiple electricity connections in close proximity. In EV charging it may be relevant to complex sites, adjacent supplies, multi-occupancy buildings or installations where separate connections interact.

Individual supply per outlet means each charging outlet has its own dedicated electrical supply or separately protected feed. It is normally assessed alongside phase availability, circuit capacity, protective devices, cable sizing and DNO/site constraints.

Internal PE breakage refers to a charger design where the charger has a means of interrupting or isolating the protective earth path internally as part of its response to a detected PEN fault condition.

IT earthing is an arrangement where the supply has no direct connection to earth or is connected through a high impedance. It is normally assessed during product selection, circuit design, installation verification and maintenance of EV charging equipment.

Maximum charging rate is the highest charging power a charger can deliver under its rated conditions, usually expressed in kW. It is normally assessed alongside phase availability, circuit capacity, protective devices, cable sizing and DNO/site constraints.

Overcurrent protection rating is the current value assigned to a protective device, normally stated in amps. It is normally assessed during product selection, circuit design, installation verification and maintenance of EV charging equipment.

PEN-fault protection is protection against hazards caused by a broken or open combined protective and neutral conductor in PME/TN-C-S supplies. It is normally assessed during product selection, circuit design, installation verification and maintenance of EV charging equipment.

PME earthing is an earthing arrangement where the supply uses Protective Multiple Earthing with a combined neutral and protective function upstream. It is normally assessed during product selection, circuit design, installation verification and maintenance of EV charging equipment.

PME protection refers to protective measures used to address risks associated with Protective Multiple Earthing supplies, especially open PEN faults. It is normally assessed during product selection, circuit design, installation verification and maintenance of EV charging equipment.

Power daisy chaining uses a supply arrangement where power is routed from one charger or connection point to another in a chained layout. It is normally assessed alongside phase availability, circuit capacity, protective devices, cable sizing and DNO/site constraints.

Power output is the electrical power a charger can deliver to an EV, normally stated in kilowatts. It is normally assessed alongside phase availability, circuit capacity, protective devices, cable sizing and DNO/site constraints.

Power supply refers to the electrical supply arrangement feeding a charger or group of chargers. It is normally assessed alongside phase availability, circuit capacity, protective devices, cable sizing and DNO/site constraints.

Rated current is the maximum current a charger or electrical component is designed to carry under specified conditions. It is normally assessed during product selection, circuit design, installation verification and maintenance of EV charging equipment.

Rated voltage is the nominal voltage range for which a charger or component is designed to operate. It is normally assessed alongside phase availability, circuit capacity, protective devices, cable sizing and DNO/site constraints.

Single-phase charging uses a single-phase AC supply, commonly found in many UK domestic and small commercial installations. It is normally assessed alongside phase availability, circuit capacity, protective devices, cable sizing and DNO/site constraints.

Three-phase charging uses a three-phase AC supply and can support higher AC charging rates where the vehicle and charger are compatible. It is normally assessed alongside phase availability, circuit capacity, protective devices, cable sizing and DNO/site constraints.

TN-C-S earthing is an arrangement where neutral and protective functions are combined in part of the supply and separated within the installation. It is normally assessed during product selection, circuit design, installation verification and maintenance of EV charging equipment.

TN-S earthing is an arrangement where the neutral and protective earth conductors remain separate from the supply source to the installation. It is normally assessed during product selection, circuit design, installation verification and maintenance of EV charging equipment.

TT earthing is an arrangement where the installation uses its own earth electrode rather than relying on the distributor's protective conductor. It is normally assessed during product selection, circuit design, installation verification and maintenance of EV charging equipment.