Power Supply Basics

What is a Power Supply’s IP Rating?

Posted by Dulcie on December 7, 2011
Posted in: Power Supply Basics

The popularity of outdoor electronics has brought the subject of a power supply’s IP (Ingress Protection) rating from almost obscurity to an everyday question. I frequently get asked about it, so I thought it would be nice subject to cover in our blog.

The IP Rating Code consists of the letters ‘IP’ and two numbers as defined in the tables below.

The first number indicates the product’s protection level against the ingress of solid objects or dust. The second number indicates the power supply’s protection against the ingress of water or other liquids.


Solids or Dust

LevelSize of ObjectType of Object
XTest not madeTest not made
0N/ANo protection
150mm or largerLarge body surfaces*
212.5mm or largerFingers
32.5mm or largerSmall tools
41mm or largerScrews
5Dust protected
6Dust tight

* Does not include deliberate body part contact




LevelProtected against
XTest not made
0No protection
1Water dripping vertically
2Water dripping at an angle
3Spray water up to 60° from vertical
4Splashing water from any angle
5Low pressure water jets
6Strong spray jets, heavy seas (ship decks)
7Temporary immersion (up to 1m)
8Permanent immersion (deeper than 1m)



AL Series - IP66-rated LED power supplies
LED power supplies, or drivers as they are often referred to, have ratings of IP66 – take the AL series from TDK-Lambda, for example. Referring to the charts above, an IP66 rating means the unit has ingress protection from Dust and Strong Jet Sprays of Water.