Ethernet technology is coming to the factory floor. Once limited to networks in office environments, Ethernet has also proven to be a robust alternative to the RS-232 interfaces traditionally used with industrial devices such as programmable logic controllers. Ethernet brings speed, versatility, and cost savings to industrial environments.
The requirements of industrial environments are different from those of offices, and there have been a proliferation of industrial standards. The most commonly accepted are the Ingress Protection (IP) ratings developed by the European Committee for Electrotechnical Standardisation (CENELEC), which specify the environmental protection an enclosure provides.
Two or Three Numbers
An IP rating consists of two or three numbers. The first number refers to protection from solid objects or materials; the second number refers to protection from liquids and the third number, commonly omitted from the rating, refers to protection against mechanical impacts.
| First IP Number
||Second IP Number||Third IP Number|
|0 No protection
||0 No protection||0 No protection|
|1 Protection from solid foreign objects of 50 millimetres or greater||1 Protection from vertically falling drops of water and condensation
||1 Protection from impact of 0,225 joule (150 grams falling from 15 centimetres)|
|2 Protection from solid objects up to 12 millimetres||2 Protection from direct sprays of water up to 15° from the vertical||2 Protection from impact of 0,375 joules (250 grams falling from 15 centimetres)|
|3 Protection from solid objects more than 2,5 millimetres||3 Protection from direct sprays of water up to 60° from the vertical||3 Protection from impact of 0,5 joule (250 grams falling from 20 centimetres)|
|4 Protection from solid objects more than 1 millimetre||4 Protection from splashing water from all directions||4 Protection from impact of 2,0 joules (500 grams falling from 40 centimetres)|
|5 Protected from dust, limited ingress||5 Protected from low-pressure water jets from all directions||5 Protected from impact of 6,0 joules (1,5 kilograms falling from 40 centimetres)|
|6 Totally protected from dust, dust tight||6 Totally protected high-pressure water jets||6 Protection from impact of 20 joules (5 kilograms falling from 40 centimetres)|
|7 Protection from temporary immersion up to 1 metre|
|8 Protection from long period immersion under pressure|