Ingress protection (IP) rating system is drafted by the International Electro-Technical Commission (IEC). Ingress protection (IP) rating classifies and rates the degrees of protection provided against intrusion (body parts such as hands and fingers), dust, accidental contact, and water by mechanical casings and electrical enclosures. An IP rating consists of two digits, for example, IP56. The first digit indicates the level of protection that the enclosure provides against access to hazardous parts and the ingress of solid foreign objects (including tools and body parts like hands and fingers). The second digit indicates the level of protection that the enclosure provides against harmful ingress of water. A larger digit indicates a higher protection level.
The following table describes the first digit.
Digit | Protection Scope | Description |
0 | No protection | No special protection against person or foreign objects |
1 | > 50 mm (in diameter) | Prevent human body (such as palm) from contacting internal electrical parts due to accidents. Prevent large foreign objects (diameter greater than 50 mm) from entering. |
2 | > 12 mm (in diameter) | Prevent fingers from contacting internal electrical parts. Prevent medium-sized foreign objects (diameter greater than 12.5 mm) from entering. |
3 | > 2.5 mm (in diameter) | Prevent tools, wires, and similar small objects whose diameter or thickness is greater than 2.5 mm from contacting internal electrical parts. |
4 | > 1.0 mm (in diameter) | Prevent tools, wires, and similar small objects whose diameter or thickness is greater than 1.0 mm from contacting internal electrical parts. |
5 | Protection against intrusion of foreign objects and dust | Prevent all objects from entering. Although dust cannot be prevented completely, the entered dust does not affect normal operation of electrical devices. |
6 | Protection against intrusion of foreign objects and dust | Prevent all objects and dust from entering. |
The following table describes the second digit.
Number | Protection Scope | Description |
0 | No protection | No special protection against water or moisture |
1 | Protection against dripping water | Dripping water (vertically falling drops, such as condensate water) shall have no harmful effect. |
2 | Protection against dripping water when the enclosure is 15 degree tilt | Vertically dripping water shall have no harmful effect when the enclosure is tilted at an angle up to 15° from its normal position. |
3 | Protection against spraying water | Water falling as a spray at any angle within 60 degrees from the vertical shall have no harmful effect. |
4 | Protection against splashing water | Water splashing against the enclosure from any direction shall have no harmful effect. |
5 | Protection against water jets | Water projected by a nozzle against enclosure from any direction shall have no harmful effects. |
6 | Protection against heavy seas | Water from heavy seas shall not damage electrical devices installed on the deck. |
7 | Protection against the effects of immersion | Ingress of water in harmful quantity shall not be possible when the enclosure is immersed in water under defined conditions of pressure and time. |
8 | Protection against submersion | Continuous immersion in water under defined conditions of pressure and time shall not damage the enclosure. |
