Electric motors are used in a wide variety of applications and are therefore exposed to different environmental conditions. To ensure that operation is not affected, motors must be protected against external influences from solid bodies or liquids. For economic reasons, it makes sense not to provide the same protection for all motors. There are different protection classes, which are regulated in IEC 60034-5 and DIN EN 60529. The protection classes are specified, for example, with IP55, where the first digit stands for protection against contact and foreign bodies and the second for protection against water / liquids. The abbreviation IP stands for "International Protection".
There are many different protection classes, which result from the different combination of first and second digit. What the individual digits mean can be seen in the tables below. For the example IP55 the breakdown is a complete protection against contact, a protection against dust in damaging quantity and a protection against water jets from any angle.
First digit:
|
ISO 20653 |
DIN EN 60529 |
Protection against contact |
Protection against foreign bodies |
|
0 |
0 |
No protection |
No protection |
|
1 |
1 |
Protected from large surface contact |
Protected from large, solid foreign bodies (Ø>50mm) |
|
2 |
2 |
Protected from finger strangulation |
Protected against medium-sized, solid foreign bodies (Ø>12mm) |
|
3 |
3 |
Protected from contact with tools and wires (Ø>2.5mm) |
Protected from small, solid foreign bodies (Ø>2.5mm) |
|
4 |
4 |
Protected from contact with tools and wires (Ø>1mm) |
Protected from small, solid foreign bodies (Ø>1mm) |
|
5K |
5 |
Complete touch protection |
Protected from dust in harmful quantity |
|
6K |
6 |
Complete touch protection |
Complete protection against dust ingress |
Second digit:
|
ISO 20653 |
DIN EN 60529 |
Protection against water |
|
0 |
0 |
No protection |
|
1 |
1 |
Protected from vertically falling dripping water |
|
2 |
2 |
Protected from dripping water falling at an angle (up to 15°) |
|
3 |
3 |
Protected against water spray up to 60° against vertical |
|
4 |
4 |
Protected from splashing water on all sides |
|
4K |
|
Protected from splashing water on all sides with increased pressure |
|
5 |
5 |
Protected from water jets from any angle |
|
6 |
6 |
Protected from strong jets of water |
|
6K |
|
Protected against strong jets of water under increased pressure |
|
7 |
7 |
Protected from temporary immersion |
|
8 |
8 |
Protected from continuous immersion |
|
|
9 |
Protected from water during high pressure / steam jet cleaning in agriculture |