EV Charging design infrastructure – Safety & Standards

With the electronic vehicle (EV) market becoming more significant in Europe in the last few years, the need for charging points is steadily increasing. The demand for the infrastructure is mostly due to the uptake of electronic vehicles as more car manufactures are now focusing their efforts in EV’s to meet EU demands. It is also evident that with surges in new EV cars sales also requires further expansion to the infrastructure, including new accessible charging points and expansion of existing charging points.  

The overall infrastructure of EV charging also includes the type of charging stations. The need for rapid chargers at convenient locations is essential for any journey; as we know any type of rechargeable battery requires charging over long period of times, EV’s are no different. The smallest EV batteries are around 20-30kW and the largest can be up to 100kW. With a battery capacity around 100kW a standard 240V household plug socket would charge the battery in around 24 hours at 2.3kW. A specialised wall box charging point would charge the battery in around 7.5 hours at 7.4kW and a rapid charger can charge a battery in under 1 hour, rated at 50kW. The availability of rapid chargers is essential for most drivers traveling long distances otherwise the whole infrastructure would be deemed impractical. 

In reality most EV owners will have a dedicated charger in the home connected to the internal household electricity supply and charge the vehicle overnight when electricity is much cheaper and there is less demand. These home chargers are either a standard 240V 13A socket or most energy suppliers will now install a wall unit that is 7.4kW/32A. 

EV Charging pyramid 

The growth of the EV market with car manufactures haw led to a variety of proprietary chargers and connection types, with each offering there own unique design. This single topic is a huge challenge within the overall design infrastructure for EV charging. One of the solution to this problem is the charging strategies. 

At the lower end of the scale are slow chargers, which are typically rated between 2-3kW and can be used in almost any home. In addition to this there are also a number of home wall chargers that can be fitted outside your house or in the garage and these wall chargers are rated at 7.4kW and are directly wired up to the ring mains. 

Fast chargers are found in most public spaces, such as car parks, shopping centres and some cases can be found in public street parking. These chargers will charge your EV at a particular rate as per the charging network. Fast chargers are rated between 7-22kW and can charge your vehicle from zero to full capacity in around 3-6 hours depending on your EV battery capacity. 

Rapid chargers are even quicker and most commonly found in car parks, where EVs are left for few hours. They come in two types, AC chargers use 43kW of power and DC chargers 50kW. The DC chargers supply power direct to the car without any AC/DC power conversion and power loss in the process. With both of these charging methods an EV would charge its battery in around 1 hour. 

At the top of the EV charging scale are superchargers, which charge anywhere between 120kW to 300kW. Tesla was one of the first EV car companies to design a supercharger at 120kW through its own proprietary connector and recently they announced a new supercharger at 250kW. Tesla claims it can fully charge its batteries in 15-30 mins across its network of over 20,000 superchargers in Europe.. These type of chargers are ideal for service stations and gas stations as they are usually situated in ideal locations for long journeys and be easily accessible. 

There are a few EV charging companies that have exceeded the 150kW that is commonly found with most superchargers. One of those companies is Swiss based ABB. ABB has launched its Terra high power DC fast charger, which can output up to 350kW, which is nearly three times the rate of Tesla’s superchargers. Unfortunately there is nothing in the market that can handle this type of charging ability, but the technology is there and is ready to be implemented for when EV’s have this capability. 

Connectivity options 

Not only are there a number of charging options within the EV infrastructure but there are also a variety of charging connectors. Each connector and charging system is incompatible with one another, which prevents a challenge within the EV industry. Here is a list of the most common types of EV connectors: 

ype 1 plug – The type 1 plug is a single-phase plug which allows for charging power levels of up to 7.4 kW (230 V, 32 A). The standard is mainly used in car models from the Asian region, and is rare in Europe, which is why there are very few public type 1 charging stations. 

Type 2 plug – The triple-phase plug’s main area of distribution is Europe, and is considered to be the standard model. In private spaces, charging power levels of up to 22 kW are common, while charging power levels of up to 43 kW (400 V, 63 A, AC) can be used at public charging stations. Most public charging stations are equipped with a type 2 socket. All mode 3 charging cables can be used with this, and electric cars can be charged with both type 1 and type 2 plugs. All mode 3 cables on the sides of charging stations have so-called Mennekes plugs (type 2). 

Combination Plugs (Combined Charging System, or CCS) – The CCS plug is an enhanced version of the type 2 plug, with two additional power contacts for the purposes of quick charging, and supports AC and DC charging power levels (alternating and direct current charging power levels) of up to 170 kW. In practice, the value is usually around 50 kW. 

CHAdeMO plug – This quick charging system was developed in Japan, and allows for charging capacities up to 50 kW at the appropriate public charging stations. The following manufacturers offer electric cars which are compatible with the CHAdeMO plug: BD Otomotive, Citroën, Honda, Kia, Mazda, Mitsubishi, Nissan, Peugeot, Subaru, Tesla (with adaptor) and Toyota. 

Tesla Supercharger – For its supercharger, Tesla uses a modified version of the type 2 Mennekes plug. This allows for the Model S to recharge to 80% within 30 minutes. Tesla offers charging to its customers for free. To date it has not been possible for other makes of car to be charged with Tesla superchargers. 

Home Charging Domestic socket – charging power levels of up to 3.7 kW (230 V, 16 A) can be reached with a domestic socket with the appropriate fusing. Your electric car will be charged via a mode 2 charging cable. We would definitely recommend a maximum charging power of 2.3 kW (230 V, 10 A) if the socket has not been checked beforehand. Domestic sockets can also sometimes be found at public charging stations. This charging method is available for all electric cars. 

Network infrastructure 

The number of EV charging points available in Europe is increasing every year as the uptake of EVs grows. This is happening much faster in some regions than others. In 2019 there was approximately 15k high powered (22kW+) charging points and in 2020 this almost doubled to 25k according to the European Alternative Fuels Observatory data. This is not only due to the advancements in EV charging but also the National Policy Frameworks (NPF) that have been put in place under Article 3 of Directive 2014/94/EU. 

One of the leading countries of EV’s is Norway, where there are over 300k registered passenger EV’s which is more than 15% of the overall car market as of 2020. The plug-in car market share has been the worlds highest for several years and has been the first country where the sale EV’s have outsold cars with internal combustion engines. There are currently around 500k EV’s in Norway, including hybrids and plug-in hybrids in a population of around 5.2 million.  

To deal with this incredible uptake of EVs is the charging network infrastructure. There are currently around 9000 charging points in Norway that span across 2500 stations according to electromaps. Not only this but it is also the most cleanest network in the world, with 98% of the electricity used to charge EV’s coming from a renewable energy source.  

Throughout Europe there are many energy companies entering the EV charging industry as they are best suited for this type of market, especially when they can offer the electricity supply using a renewable energy source such as wind, solar and hydro power. Dutch company Fastned are a leading EV charging specialists with its recently introduced charging stations that independently relies on the solar panels. This solution is a cost-effective way of charging EV’s as previous existing solutions require power from a local power stations. New EV’s charging stations would therefore need to tap into the already existing power network which could but further strain on the energy network as well as being located in public places.  

Some companies are looking to EV to change the way they do business, as well as reaching to an ever evolving demographic. Oil companies such as BP and Shell have installed EV chargers in almost all of its service stations throughout Europe, allowing them to keep up with trends and expanding their customer base. Moreover, the majority of service stations are strategical placed for easy accessibility for most drivers, which is a great benefit to the overall EV infrastructure.  

EV charging Safety 

There are two aspects to charging an EV, the charger itself and the charging cable with the relevant connector. The EV charging points fall under the IEC 61851 of the EU directive, which currently is evolving and always under continued development. The charger cable and charging connector falls under the IEC 62196 EU directive for plugs, socket-outlets, vehicle connectors and vehicle inlets. These EU standards are set in place for the safety of the equipment as well as the end user. For example, power is not supplied to the vehicle unless a compatible vehicle is connected and the vehicle is also immobilised while the cable is connected.   

Under the IEC 62196 directive are also sub-directives (IEC 62196-1 and IEC 62196-2) that explain in detail the design of each type of plug and its specifications. It was introduced to allow compatibility between products of different manufacturers. 


Type 1 – Widely used in the US and Japan, was originally design by manufacture Yazaki and was published under the SAE J1772 standard in the US. The connector itself features a round housing, with a notch on the vehicle inlet to determine its orientation when in use. It allows a operating current of 32A and a maximum current of 80A but only in the US. 

Type 2 – Also known as a Mennekes connector, it has a round housing with one side flattened to allow correct orientation when in use. It also features several pin and sleeve contact for up to four AC conductors, a protective inductor and also two signal pins to control its functionality. Type 2 connectors also have an additional feature where the contacts cannot be touched by a standard finger to prevent electrocution and in the newer version of this connector it has been further enhanced by including shutters. The connector can operate up to 63A with a maximum current of 70A available for single phase applications. Within the EU it is a requirement that all public AC chargers be fitted with a type 2 connector and socket. 

Type 3 – This configuration unlike the other two consists not only of a plug and socket but also the vehicle coupler. This particular connector features an oval housing with a flattered side for correct orientation when in use. There is also touch protection in place in the form of shutters over the pins to prevent any human contact and also there is a locking mechanism when inserted into an inlet. This connector allows a single phase charging up to 16A without control pilot contact, 32A with and three phase charging up to 63A. 

As we already know, the demand for EV charging stations is very high across Europe, and it is also vital to ensure that every charge point is operational; otherwise, it could put further strain on the infrastructure. Several issues can occur that could lead to a faulty charge point, such as overloading the power supply, equipment and system failures, and overheating. Many countries across Europe have already started to address this issue by ensuring that each public charging station complies with the relevant European safety standards for electrical systems. The regulation that must be applied to each station includes the following: 

Following HD 60364, all qualified electricians are required to perform tests on a low-voltage system after installation. The tests include measuring, inspecting and testing different operating modes of the charge station in question. The tests carried out would consist of measuring the continuity of the protective earthing conductors and the functionality of the built-in RCD, and the insulation and earth resistance.  

Test adaptors for EV charge stations

Suitable for vehicle charging stations with charging mode 3

Fluke T6-1000 PRO Electrical Tester

The T6-1000 PRO Electrical Tester measures voltage up to 1000 VAC and current up to 200 AAC, all through the open fork and without test lead contact to live voltage.

Safety is not only for the chargers themselves but every aspect of the charging equipment, including the design of the charging cables, which must comply with HD 60364-5-52. This also includes the testing of the temperature during one hour of continuous operation. The results would ultimately test the risk of overheating in both the charging unit and the charging cable, preventing the risk of fire damage or burnouts. A maximum temperature increase of 45 Kelvin is tolerable. These risks can easily be identified using thermal imaging cameras. 

FLIR Exx-Series

Designed for thermographers who regularly inspect large numbers of objects over the course of a day, FLIR Inspection Route guides the user along a pre-defined route of inspection points so they can collect images and data in a structured manner.

Fluke TiS55 Thermal Imager

Take your plan for a proactive maintenance (PM) program and turn it into reality. To get started, you need features that make it easy to set up your image organization and inspection routines.

Part of the testing procedures for EV charging stations does not lay with the initial installation, but it is also imperative that period testing is carried out through its lifespan. Clause 6.5 of HD 60364-6 must be followed to include the pilot signal’s electrical safety and operating tests to conform to EN 61851-1.  An Oscilloscope must be used to carry out this test of the PWM signal. The graphical data returned should allow an engineer to assess any fault within the charge signal at any point between the charge station and the vehicle in question. 

Handheld Oscilloscope Bundle, 4x 500MHz, 5GSPS, Rohde & Schwarz

Lab performance in a rugged and portable design – the perfect multipurpose tool for the lab or in the field.

Handheld Oscilloscope, 4x 200MHz, 2.5GSPS, Fluke

The Fluke ScopeMeter 190 Series II combines the highest safety ratings and rugged portability with the high performance of a bench oscilloscope.

The future of EV infrastructure 

As more and more users are now investing in electric vehicle so does the call for more charging points to be made available at convenient locations. There are also a number of government backed scheme available to help alleviate the some of the pressure by installing EV charge points at companies for workers and also at the home. 

There is also a global climate change policy that is also part of the driving force behind “going electric” and car manufacturers are slowly adapting their business from combustion engine to fully electric. Just recently Ford announced it would go all electric by 2030 across all its models. 

There is no doubt the charging infrastructure is going to be progressed over a number of years but the system that is currently in place is a great foundation to be built upon in the future. 

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