Electric Vehicle (EV) Chargers
EV chargers are still relatively new technology and can vary greatly between manufacturers and models. To comply with current wiring regulations an EV charger will need to have some important safety features to ensure the installation is safe and the car will not become live during fault conditions, which can lead to electrocution and even death in severe cases.
An EV charger is a large load which will be connected for a long period of time and so it may be necessary to contact the District Network Operator or DNO for permission to install the charger on the existing supply. Therefore, before installing an EV charger, a survey of the existing electrical system should be carried out at the proposed site to ensure certain criteria is met.
Payne Electrical Services can conduct a survey and will need to assess the following:
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The size of the incoming fuse and the maximum demand to ensure the supply can handle the additional load of the EV charger.
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The earthing arrangement of the installation.
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Whether the main water and gas supply and any other extraneous conductive parts are earthed.
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Whether the existing consumer unit has RCD protection and any spare ways which could be utilised for the charger.
Although it is not essential, it is highly recommended an Electrical Installation Condition Report (EICR) should be carried out on the existing installation prior to installing the EV charger. This will uncover any faults, dangerous or potentially dangerous conditions within the installation. Upon completion of the survey Payne Electrical Services will then be able to provide a more accurate quote to install the EV charger after deciding upon a preferred model of charge point.
Most modern EV chargers can measure the power consumption being used by the property. While commissioning the charger our engineers will enter the size of the main fuse supplying the installation. This will prevent an EV charger from overloading the supply and blowing the main fuse. For example, if you have a 60 Amp main fuse and a cooker is running at full power rated at 30A and all the other appliances plugged in to a socket circuit amounts to 15 amps the charger will reduce its charging capacity from 32A so the total load being used by the property is below that of the main fuse.
Cooker (30A) + Appliances (15A) = 45A (Total connected load)
Main fuse (60A) – Total connected load (45A) = Reduced EV charging capacity (15A)
This will increase the time the charger takes to fully charge the Electric Vehicle however it will be safer and will protect the main fuse from blowing which would lead to loss of electricity to the premises. It is also recommended to install a data cable to the charger rather than relying on a possibly unstable Wi-Fi or mobile network connection.
There are various different sizes of EV charger available, the more powerful the charger the faster your car will charge. How long it takes to charge an EV will depend upon the size of the battery. A typical domestic EV charger is 7kW which will take approximately 8 hours to fully charge from empty. More powerful chargers will usually require a 3-phase supply so are usually aimed at the commercial market such as offices, car parks, service stations and super markets. The electricity consumption is monitored and so the owner of the charging point can charge for the electricity usage accordingly.
Another variable to consider when deciding upon which model of charger to install is whether you want a tethered unit which has a charging cable built into the charger or an untethered unit where you will have to supply your own charging cable.
A Wallbox Pulsar Plus tethered EV charge point installed by Payne Electrical Services at a job in Leigh.
A 7kW Zappi EV charge point installed by Payne Electrical Services at a job in Flixton.
There is advantages and disadvantages to both. A tethered unit will be slightly more expensive to purchase from the manufacturer however will be ready to plug and play. An untethered unit is a more compact and aesthetically pleasing installation and slightly cheaper however the customer will need to provide their own cable and there have been cases of thieves stealing the cables while the car is charging.
Payne Electrical Services recommends purchasing a charger which has O-PEN protection and an RDC-DD built in as standard. Although it will be a slightly more expensive initial outlay it will eliminate the need for our engineers to install these safety features upstream of the charger and save the customer money in labour and additional equipment.
It is possible to charge an Electric Vehicle using a standard 13A plug socket however this is a temporary measure and not recommended as the charger is unlikely to have the above safety features built in. The following photo shows a socket we came across which was used to plug into a cheap car charger from Amazon. Luckily the socket was RCD protected and it tripped at the consumer unit however this could have potentially led to a house fire.