Industry News

Testing EVSE in Public Settings to New Zealand Standards

Even the smallest towns are having public charging stations installed...

Overview of Public EVSE Testing

The public EV charging network being installed throughout New Zealand is coming along nicely. Even the smallest towns are having public charging stations installed, as councils recognise the benefit of having a charging station that takes up to 20 minutes to get a good charge, as opposed to the minute we're used to at petrol stations. This means more foot traffic around town during charge time, an unintended benefit for our economy.

All fast charger stations use DC that connects directly to the car battery. AC chargers must first connect to a converter in the EV, which both slows down the charge time and shortens the battery life a lot faster than DC/fast charging.

Any charger used in a public must be certified yearly, with the first test being within the first 12 months of installation.

Cable Modes Used in Public Situations

It's important to note that there are different public charging stations, and some allow for all Modes of cable to be connected. Charging stations often come with charge cables to fit the most common Modes and connector Types (See Types 1 and 2 here).

MODE 1 OVERVIEW

Mode 1 cables are not permitted to be used or installed in any public EVSE (electric vehicle service equipment) in New Zealand. They are outdated and inefficient.

MODE 2 OVERVIEW

Also not permitted for public EVSE installations, Mode 2 connectors are more advanced than Mode 1, but still offer very slow charge times, are single phase only and connect to standard socket-outlets.

MODE 3 OVERVIEW

Mode 3 offers both single phase and 3 phase charging. While still AC only - which relates to a slower charge - the 3 phase connections offer faster charging than both Mode 1 and 2 connectors.

This type of cable is recommended for both domestic and public (in conjunction with Mode 4) installations as the superior AC charger supported by the most EV brands. Despite this, the higher price tag will still see many domestic installations using a Mode 2 charger. See our domestic EVSE testing article for more information.

MODE 4 OVERVIEW

The current standard for public charge stations, Mode 4 is the only internationally recognised DC charging cable.

Directly charging the EV battery, Mode 4 can provide up to 80% of a batteries maximum charge in around 20% of the time an AC charger will take to reach the same volume.

Because Mode 4 is a direct charge system, battery life and condition are extended. Assuming people using public stations are doing so during the day, it also creates less load on the national grid.

CONNECTOR TYPES

There are only two types of connectors which you will see in conjunction with the above Modes - also sometimes called connectors but technically cables.

TYPE 1: Older and on its way out. Type 1 is not able to provide 3 phase charging and is mostly seen on older models, especially Japanese and other Asian makes.

TYPE 2: The current standard in cable connections, type 2 is able to provide both single and 3 phase charging, making it the obvious choice for late model EVs. Most European makes come with type 2, and NTZA recommend it for public and domestic installations.

Current Testing Guidelines

Every EV charging outlet must come with a dedicated RCD. Every public EVSE will come with dedicated cables in Mode 4, with Mode 3 as an option. Some also provide socket-outlets for EV owners to use their own cable. Regardless of type, each socket-outlet and in-built cable must have its own RCD. It cannot be assumed that a BYO cable will have an RCD.

This list is compiled in part by Worksafe. Note that new public installations must be tested before the first 12 months are up, and every 12 months thereafter.

Refer to Part 5 of the Electricity (Safety) Regulations 2010 for official testing guidelines.

The following must be inspected and tested every 12 months:

  • 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
  • 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'

Re-tagging involves sticking a non-reusable tag with the following details:

  • Date of assessment
  • Date of next assessment
  • EWRB licence number
  • A statement from tester stating compliance
  • Details of EV charger operator

Where to Find The Regulations

Worksafe are still working through the regulations around EV installation and testing in New Zealand. While we do have good guidelines at present, they are still being worked on so be sure to check them if you have an upcoming job.

You must always ensure the equipment you are testing is compliant. Never assume the installation process was fully compliant. Cover your own work by referring to Part 3 of the Electric Vehicle Charging Safety guidelines. This covers the requirements for EVSE in more detail, so be sure to keep a copy on hand and to read it with Part 1 and Part 2.

You'll need PAT testing, in which case the Megger PAT400 Series will keep you over compliant, including testing RCDs and 3-Phase outlets.

The best test and measure tool for public chargers is the Megger MFT1800 Series, which covers Continuity and Insulation testing, Loop testing, RCD testing and Earth testing.

Want to know about testing domestic EVSE installations? See our article here.