IP protection levels

Reading time < 1 minute

In electrical engineering, IP protection classes use two numbers to define protection against dust (1st number) and moisture (2nd number). For example, IP 45 means that there is protection against dust > 1 mm and water jets. In general, the higher the number, the higher the protection.

A list of all types of protection can be found in the following list:

1st digit	Scope of protection	2nd digit	Scope of protection
1	Protection against large areas of contact with the hand. Protection against foreign bodies ∅ > 50 mm	1	Protection against vertically falling water drops
2	Protection against contact with fingers. Protection against foreign bodies ∅ > 12 mm	2	Protection against drops of water falling at an angle from any angle up to 15° from vertical.
3	Protection against contact with tools, wires or similar. Protection against foreign bodies ∅ > 2.5 mm	3	Protection against water from any angle up to 60° from vertical.
4	Protection against contact with tools, wires or similar. Protection against foreign bodies ∅ > 1 mm	4	Protection against splash water from all directions.
5	Protection against contact. Protection against dust deposits inside.	5	Protection against water jets (nozzles) from any angle.
6	Complete protection against contact. Protection against dust ingress.	6	Protection against strong jets of water from any angle.
		7	Protection against water penetration during temporary immersion.
		8	Protection against pressurized water when permanently submerged.

CEE plug connections

CEE plug connections on caravans or motorhomes usually correspond to protection class IP44. Only versions with a Renk / bayonet lock meet IP67.

The question of whether such a CEE plug connection remains tight even in heavy rain can be clearly answered with yes from the table above: IP44 is tight with regard to “splash water from all directions”.

It is important to make sure that the plug is fully inserted and the plug flap is locked into place. It is also helpful to secure the cover flap located above the plug connection with a strong “canning rubber” (or similar) over the plug against being hit by gusts of wind.