What is IP , What do the two digits after IP mean?

Ingress Protection (IP) ratings is a two-digit rating system used to refer to the level of protection offered by an electrical enclosure against solids and liquids. Ever seen some electrical products labelled IP65, IP21 or different digit numbers and wondered what they meant? This article will guide you into understanding what it means.

The first number refers to protection against solids, and the second against water. The higher the number the more you can be assured for better the protection. For example, IP 68 is the maximum protection rating.

Manufacturers often replace a number with X to indicate that the enclosure lacks a rating for that specification.

Origination ?

IP ratings originated from the IEC 60529 standard that was prepared by IEC Technical Committee 70.

​“IEC is an international standards organization that prepares and publish standards for all electrical, electronic and related technologies” – IEC

Why are IP rating important.

Having a universal IP rating system allows for single language between buyers and sellers. This is so that buyers and users can be confident of how safe it is to use certain electrical or mechanical goods in specific environments and applications.

Compared to terms such as ‘waterproof’ – which do not provide a clear definition of precisely where and to what extent an item can resist moisture ingress. An IP rating provides a far more specific account.

Electric and electronic equipment deteriorate or malfunction when water or dust enters the device. Its therefore crucial for an installer to understand the conditions each product can be installed in.

Where is the standard applicable?

The IP rating system rates the degree of protection that an enclosure provides for electrical equipment with a rated voltage not exceeding 72.5 kV.

Below is a full description of which digit means and the max available protection. The poster below is valuable for reference incase you face a supplier scam offering “IP79 protection” on an inverter.