In this example we’ve installed a Myenergi Zappi EV changer. Here we’ll talk about considerations of installation such as: the type of cables to use, and all the surrounding requirements of EV home charger installations, other than the installation of the unit itself.
Watch the video below which gives an overview of this EV home charger installation in West Yorkshire, then read on for more detailed information. Please drop us a line if you would like to discuss a similar installation in your home.
MYENERGI ZAPPI EV CHARGER
The first solar EV home charger installation!
The Zappi is the world’s first EV charger with the functionality to be able to utilise the energy specifically generated by your solar PV and wind generation. The easy to interpret display shows when your vehicle is drawing energy from the grid directly, and when energy is being used by any micro generation tech you have in your home. Charging modes can be altered so that charging only occurs when renewable energy is available (Eco mode), or fast mode simply pulls what the car needs directly from the grid.
It also functions as a regular EV drawing energy directly from the grid as required – micro generation can be added to your home at a later date.
Remote access is provided by the Myenergi app via a hub which communicates wirelessly with the charging unit.
Finally, as discussed below, the unit contains cutting edge safety technology which simplifies the installation process and therefore installation costs for the customer.
For more details, take a look at the Myenergi website.
INSTALLATION CONSIDERATIONS
Dangers associated with earthing an EV home charger installation
A large proportion of UK households have what is know as a TN-C-S or PME earthing facility in their home. To keep things brief, this means that the neutral and protective earth conductors are combined – also referred to as the PEN conductor. This is the case between the transformer in the street supplying your home and the service head in your home (where the main cut out fuse is located). Thereafter, these conductors are separated in you installation to provide a line and neutral for regular function of your various circuits, plus a protective earth to ensure safety in the event of a fault.
In the event of a loss of the PEN conductor external to the property, a dangerous voltage may become present under fault conditions on an exposed conductive part – such as your electric vehicle. The usual method of additional protection with an RCD would not function in this situation; there would be the chance of a potentially fatal shock.
No earth rod required for this EV home charger installation
The way around this according to the IET wiring regulations is to install an earth rod for your EV home charger installation, and not use the earth provided by the network operator. This raises issues of both extra cost to the customer, and difficulties for the installer to ensure that a good enough connection to earth can be achieved and therefore protective devices trip to keep the end user safe.
There are certain situations where an earth rod are not required for an EV home charger installation: one of which is that if protective technology is built into the EV charger itself which recognises the loss of the PEN conductor, then a separate earth rod need not be used. The Zappi has technology built in to monitor and automatically disconnect if this is the case.
In this EV home charger installation, we were therefore able to use the main earth to the building to supply the garage consumer unit, and subsequently the Zappi unit.
