Degree of soiling
The degree of soiling describes the environmental influences such as dust, moisture and aggressive substances that can affect a component in terms of insulation(air and creepage distances).
IEC/EN 60664-1 and VDE 0110-1 define four degrees of contamination:
– Pollution degree 1: There is no or only dry, non-conductive pollution.
– Pollution degree 2: Only non-conductive pollution occurs, which occasionally becomes conductive due to occasional condensation.
– Degree of contamination 3: Conductive contamination occurs or dry, non-conductive contamination that becomes conductive because condensation is to be expected.
– Degree of soiling 4: The soiling leads to permanent conductivity caused by conductive dust, rain or moisture.
For industrial use, components that can be classified in class 2 have proven their worth.