Safely charging your electric vehicle at home
Find out about the precautions we recommend to keep you and your family safe when charging your electric vehicle at home.
Electric vehicles use electricity to charge, and just like other electronics in your home, there are some precautions you should take to ensure you and your family are safe using this equipment.
Quick safety tips for electric vehicle charging:
- Only use electric vehicle charging adaptors supplied by the vehicle manufacturer or by an electric vehicle supply equipment (EVSE) manufacturer.
- Don’t use any household adaptor (such as a multi-box, double plug or a travel plug) between EVSE such as an In-Cord Control and Protection Device IC-CPD and a socket outlet.
- Never use damaged or modified charging equipment – such as overseas equipment that has been fitted with a New Zealand plug.
- Don’t use any faulty charging equipment, get it checked by the manufacturer.
Installing a charging unit?
Electric vehicles are growing in popularity and charging at home can be the easiest option.
However, as batteries improve and capacities rise, new models of EVs with bigger battery capacities will take longer to charge then those with smaller batteries. Depending on your circumstances, for example how far away the nearest fast charger is or how far you drive daily, it might be worth investing in having a dedicated wall-mounted charging unit installed at home.
Presently most users have a charging unit that plugs into a normal socket at home. These units will supply your vehicle with up to 10A, which is plenty to charge EVs with a range of 200 km or less overnight. But vehicles with bigger batteries, such as a Tesla, would not charge overnight if the battery was nearly empty without using a higher-powered EVSE.
Note: If you are only topping up the charge, a 3-pin IC-CPD might be all you need.
If you decide to install a wall-mounted unit at home, or are having one installed in the workplace, it must be done by a registered electrician.
A registered electrician should follow our EV charging guidelines.
Note: Depending on the age of your wiring, it may need to be upgraded or new wiring installed, as high-draw devices, such as EVSE, can create heat, which can be a fire risk with older wiring that is not designed to cope with the high demand.
We recommend you also ask your electrician to install a Residual Current Device (RCD) to keep you and your family safe. These devices will turn off the power if they detect a fault.
There are several types of RCD depending on what they are being used for. The most appropriate one for Electric Vehicle charging is a Type B RCD. If your electrician doesn’t advise you need an RCD, we suggest that you insist that one is installed.
Note: The more common Type A RCD that are found already installed in many houses are not suitable to protect you from all the faults that an EV or EVSE may give.
Buying electric vehicle supply equipment
Before you purchase any electric vehicle supply equipment (EVSE), such as a wall mounted charging station, we suggest requesting a copy of the SDoC (supplier declaration of compliance). You should give a copy of this to your electrician to review.
This document is your assurance that the EVSE is suitable for use in New Zealand. If the company can’t supply one, we’d recommend that you don’t install or use the the EVSE until its safety can be verified.
The SDoC is required of any supplier of medium-risk declared articles, which includes electric vehicle supply equipment, washing machines and clothes dryers.
Modified electric vehicle charging equipment
Never use any EVSE, such as a supply cable or an in-cord current protection device (IC-CPD) that has been modified in any way (including the labelling).
We have seen examples of equipment designed to work in other countries that have different power supply systems to New Zealand, which have been modified with a New Zealand plug or caravan plug. This is can be illegal and potentially dangerous.
TIP: If you suspect that the charging equipment has been modified, for example, a plug that doesn’t look right, don’t use it and check with your electrician to see if it has been modified.
If your electrician (or a car dealer) says that the modified equipment is safe to use because it complies with AS/NZS 3760 or it has had a tag or label applied, this is wrong. This standard is designed for handheld power tools and extension leads and provides no assurance of safety for electric vehicle supply equipment.
Electric Vehicle Supply Equipment (EVSE)
This includes anything you might use to charge an electric vehicle. Charging stations, IC-CPD, supply leads and socket-outlets are all examples of EVSE. Suppliers of EVSE in New Zealand must prove, through testing, that their equipment is safe for you to use.
In Cord Control and Protection Device (IC-CPD)
This is part of a cable or plug and vehicle connector, which performs control functions and safety functions, such as shutting off the power if there is a problem.
This allows cars with different connections to use charging equipment and should be supplied by the vehicle manufacturers. Plug adaptors that may be used to use or charge electronics from different countries should never be used to charge an EV. They can be a fire or safety hazard when charging an electric vehicle.
Residual Current Device (RCD)
An RCD is a sensitive safety device that switches off electricity automatically if there is a fault. An RCD is designed to protect against the risks of electrocution and fire caused by earth faults. For example, if you cut through the cable when mowing the lawn and accidentally touched the exposed live wires or a faulty appliance overheats causing electric current to flow to earth.
Type B RCD
A special type of RCD that can handle the different types of faults that EVSE and EV’s can place on the wiring in your home