Folding Plug

Ever thought of the fact that however portable and sleek your laptop or latest gadget is, the huge rectangular plug with its 3 bronze pins sticking out totally diminishes the definition of "sleek"? No matter how innovation is done on every part of an electronic device, the plug is the one with almost nonexistent change as far back as anyone could recall.

Folding Plug can, as its name suggests, be folded and carried with greater mobility (image taken from The Guardian).

IP Rating - Immersion vs Water Jet

Followers of this series of articles on IP rating will recall that a higher number on the 1st numeral will satisfy the requirements of a lower number (i.e. IP6X will mean that it passes all requirements from IP1X to IP6X, revisit here if the reader is interested). It would be prudent to note that such is not the case for the 2nd numeral.

An IPX4 test in progress. The semicircle apparatus sprays water through tiny nozzles lining the inner circumference. The apparatus is designed such that the water spray will reach the product from all directions. Notice that the spray is constrained to the top of the product, and the bottom is free from its direct effects (image taken from Qualilab).

The reason behind this is the difference in test requirement: 

• IPX1 to IPX6K, and IPX9K requires the product to be subjected to a flow of water impacting on the product 
• IPX7 and IPX8 requires the product to be immersed in a body of water.

In order to understand the test requirements, it is essential to first understand the application of the product in an environment prone to water ingress. Water ingress into the product could come in two different scenario - the product could be sprayed on by water jets, or it could be dropped into a body of water for a determinate period of time. It is possible to be subjected to both scenarios throughout the product's application lifetime as well.

IP Rating - Waterproof

Just as it would be difficult to judge the level of protection of "dustproof" products, the same applies to the term "waterproof" - it gives no indication the level of protection the product affords apart from the fact that it is protected against water ingress.

A waterproof iPod Stereo Case - how would you judge the term? Will the casing be free from water ingress if submerged for more than 1 hour? How will an engineer judge the term "waterproof" for critical engineering equipment? (image taken from Marine Audio and Stereo)

The 2nd code element of the IP rating helps shed some light on the level of protection, which is listed in the below table. The technical term usually associated to this code element is "protection against liquid ingress".