IP rating -
When designing a system we need to make certain the product selected is reliable with a long life.Part of that process is determining if the product is appropriate for the application environment. But what are some of the requirements ? Water proof,Dust-tight.This descriptions need to be quantified. This is what IP ratings provide.
IP - Ingress protection
International standard, Easily defined, Put measurable,testable numbers behind ratings.
What do the number mean ?
Refer the image for more details about IP rating.
First number is protection against solids.
Second number is protection against liquids.
How to compare IP rating to NEMA rating ?
There is no direct equivalence of IP rating to NEMA rating. However the following table shows the relation of IP to NEMA ratings.NEMA codes also addresses corrosion resistance.