What we are covering:
When it comes to testing EVSEs (Electric Vehicle Supply Equipment), namely chargers, there are several types currently installed around New Zealand.
The standards for domestic and public installation and charging are different. We're covering domestic installation testing methods and standards here. See our article on public testing methods for standards and regulations relating to public charging systems.
It's important to note that at the time of writing (early 2019), the Worksafe standards for installation and testing of EVs in New Zealand may change. We'll be referring to the Worksafe Electric Vehicle Charging Safety Guidelines 2016, AS/NZS 3000 and IEC standards.
Domestic installations can be as simple as a dedicated socket-outlet, although this is not the most efficient way to charge an EV or draw from the grid. Instead, an EVSE panel is recommended for installation in a watertight environment, such as the garage, or with an approved all-weather casing (generally supplied as part of the EVSE). Please note that Commando (caravan) plugs are not compatible.
MODE 1 OVERVIEW
Out of the four Modes used in charging systems, Mode 1 has largely been excluded from New Zealand use. This is mainly due to the lack of a dedicated RCD. The technology is increasingly outdated and ineffective. Older models come with Mode 1 charging cables, however we don't have many older models in New Zealand.
Mode 1 chargers can be used both as backup systems and for domestic used with a standard 250V 10A socket. However, no dedicated socket/outlet may be installed for a Mode 1 charger.
MODE 2 OVERVIEW
Currently seen as the standard for low budget installations, mode 2 will be the option installed in many private homes. The connection is generally a standard socket-outlet, limited to 32A, and almost always single phase.
The cable has a 'smart' control box between the socket-outlet and EV, which includes an inbuilt RCD and provides basic control features to the charging cable.
Mode 2 is improved on Mode 1, however it's installation is becoming more regulated as it becomes clear the charging capacity is low to the point of having negative effects on the power grid as EV use grows.
MODE 3 OVERVIEW
Again improved on Mode 2, Mode 3 is the new standard in domestic installations. The charge cable is again smart, and has the option to be single and 3 phase as well as having the potential for both AC and DC charging - making it the current clear choice for both domestic and public installations.
MODE 4 OVERVIEW
A public installation, DC charger. We will cover this more in the public installation article.
Every EV charging outlet must come with a dedicated RCD. If the domestic charger you are testing has more than one outlet, each must have their own RCD.
This list is compiled in part by Worksafe. Refer to Part 5 of the Electricity (Safety) Regulations 2010 for official testing guidelines.
The following must be inspected and tested:
- All cables, leads and plug
- RCDs and any Overcurrent devices are operational
- Functional EV check
- Earth continuity protection
- Ensure compliance with the most up to date WorkSafe guidelines as something may have changed since your installation [LINK]
- EV charger safely disconnects if there is a fault
- Earth continuity protection is operational
- If installation is outdoor, comply with IPX4 in accordance with AS 60529
- Appropriate protection co-ordination is achieved – LV supply cable circuit and protection should be tested as per AS/NZS 3000'
As always, but especially so with EVs, standards and compliance demands need to be checked regularly.
Keep up to date with Worksafe.
You must also ensure the equipment you are testing is compliant. Part 3 of the Electric Vehicle Charging Safety guidelines covers this in more detail, so be sure to keep a copy on hand and to read it with Part 1 and Part 2.
Of course, AS/NZS is always applicable and referenced.
The best test and measure tool for domestic chargers is the Megger MFT1800 Series, which covers Continuity and Insulation testing, Loop testing, RCD testing and Earth testing. For PAT testing of EVSE used in private commercial settings, the Megger PAT400 Series is the only machine you need.
Want to know about testing public EVSE installations? See our article here.