Understanding Water Resistant IP Ratings

At OEM Audio, our philosophy is to sell products which perform a specific purpose and to maximise your driving experience. Our premium EV Charging products have been trusted by over 100 car dealers in New Zealand to perform. Since 2016, we have been at the forefront of practical design, offering a durable product often exceeding current safety standards. We have also helped customers understand what EV charging products are right for their needs – as there are some misunderstandings about what the product can do and how it needs to be cared for. Paul O’Connor, Owner/Director of OEM Audio will answer some of the most frequently asked questions in simple terms.


Paul O’Connor – Making an EV Charger water resistant requires number of components. At OEM Audio we look at all aspects of water ingress protection. Not only are the materials important but the manufacturing and aftercare components are equally important. Technically the hard case, membrane and components of EV Power EVSE play a huge role in the life of the product. But don’t forget that the right care during ownership needs to be taken in order to ensure that the product meets it’s expected lifetime. We offer a two-year warranty on our products but we know that there are many EV Power products still being used well after this period and that is part of our commitment to the sustainability principles followed at OEM Audio ltd.

Fig. 1. Chart showing laboratory conditions for IEC 60529 test (NB: products do not have power for the durantion of the test).


Paul O’Connor – Yes, we are a small business with loyal customers and we want to do things in the correct, legal manner. It’s common sense that water and electricity do not mix but Standard IEC 60529 outlines which international standards must be met for an EV Charging Connector. Part of this international standard is a water and dust ingress protection (IP) test. If the enclosure meets the standard then a rating is issued by a certified testing laboratory.

Our EV Power products are tested independently in a certified laboratory to IEC 62196 and IEC 60529 standards.

  • IEC 62196 refers to general safety requirements of EV charging.
  • IEC 60529 includes an IP test.


Paul O’Connor – This is a high-pressure test that involves a jet of water from a nozzle of a certain diameter projected at the product from a certain distance for a specified amount of time. A pass is achieved by the Equipment Under Test (EUT) when there is deemed to be no harmful effects to the product being tested. The test is not completed with the equipment in use, warm, over hours and hours, or with wind.

Simply, an IP rating indicates how well a product resists water and dust.

Ingress Protection (IP) ratings have two digits:

  • The first states the level of solid/dust resistance the device has been certified for. It has a maximum rating of 6.
  • The second digit relates to water resistance.

In reality, even the highest immersion rating of “8” has a maximum depth and duration, meaning the IP scale has no true “waterproof” rating.


IP rating assessment has limits

  • IP ratings are assessed in a lab, with products immersed in still, clean water.
  • The test doesn’t account for real-life situations.
  • The devices don’t have to be on during testing – if an electronic device is powered on underwater and is running programs, its internal temperature and pressure will increase, negatively affecting the depth of water the product can withstand. Heat can cause the case to expand which may allow water to enter the IC-CPD box. See Fig. 1



Paul O’Connor – Buying EV charging equipment based on one number created in static lab test is the biggest mistake a lot of people make. The IP number is a test rating given when forcing water and dust at a product (such as an enclosure) in a very controlled environment. It’s no indication to how the EVSE is going perform in the real world. One number is not going to be enough when the conditions get tough.

The IP54 (Ingress Protection Rating) means our cables will operate in dusty conditions and will resist splashes of water while mated. However, the charging process is not fully water sealed and the cables should not be submerged in water or operated in persistent rain.

In real-life an IP66 rating should allow outdoors use of a portable charging cable, however where there is persistent rain, hours of driving rain, the EVSE should be offered some form of protection as these conditions are not covered by its IP66 rating.

If a device is labelled as water-resistant it means that the device’s construction makes it more difficult for water to get inside of it.


Paul O’Connor – Getting the maximum life out of your EVSE requires a bit of care. During use the product will heat up. This can affect the protection the enclosure provides the internal space from water. Seals can warm up and expand. So just like a waterproof rating given to a sports watch, care must be taken to ensure that the portable charging cable is offered some shelter.

This doesn’t mean your EV charging equipment has not met its IP rating or has reached the end of its life.

  • It can be put in a protective box, kept out of puddles and persistent rain.
  • Use the protective caps.
  • Don’t drag the product along the ground.
  • Drying the cable before storage is also going to extend the life of the product.
  • Don’t store outside without shelter when not in use
  • Don’t allow mud or insects to enter the control box.

There are a lot of considerations to make when choosing the right EV charging equipment for you and your family or business. But rather than choosing the cheapest option we recommend choosing a WorkSafe-compliant product which has met international standards, offers an industry leading warranty sold by a reputable company. Having a good understanding of your EV charging equipment, how it performs and how to care for it is crucial. Treat your EV products with care to ensure durability and safety.


What we will do:

  • Provide a product which is fit for purpose.
  • Ensure products meet all safety standards as set by New Zealand law.
  • Provide written instructions outlining safe care and use of EV Power EVSE.
  • Provide information relating to safe use and care of EV Power products online.
  • Provide a warranty consistent with industry standards.
  • Provide customer assistance Monday -Friday 8:30 am – 5:30 pm.
  • Meet our obligations under the Fair-Trading Act 1986
  • Meet our obligations under the Consumers Guarantees Act 1993, and offer a remedy where the EVSE becomes faulty after an activity that should be covered by its IP rating.

You can’t claim under the Consumer Guarantees Act if:

  • You used the product in a way that a reasonable consumer would not.
  • You used the product so much that it is reasonable that it broke.
  • You broke or lost the product.
  • You modified the product, and this is what caused the issue.
  • The product is second-hand.

You’ve chosen EV Power gear because we have tested it. We will stand behind our product. Every EV Power product is created for use in New Zealand conditions, so we know if you use it for what it is designed for, then it will last.

We offer a warranty on our products. This warranty is null and void if the product is used in an application that the product has not been designed for or intended for, or if it has been incorrectly used or stored. Please note that EV Power products are not indestructible. Mud, water, careless use causing continuous abrasion can push the EVSE beyond the limits of the case, cable and it’s design. We ask that you understand the intended application of your EV Power product and enjoy using it within those applications.

If your EV Power product has a defect please call us.

Paul O’Connor – Director/Owner OEM Audio Ltd