Каталог Weidmuller: Electronics - Analogue Signal Conditioning

Glossary
Technical appendix/Glossary
Pollution severity level
The pollution severity level specifies the conditions of the immediate surroundings. It
is defined in DIN EN 50178, Section 5.2.15.2.
The pollution (contamination) severity level should be used to determine the required
creepage distance for the insulation. Pollution degree 2 is the default specification.
• Pollution severity level 1
There is no contamination or only dry occurrences of non-conductive pollution.
This pollution has no influence.
• Pollution severity level 2
There is only non-conductive pollution. Temporary occurrences of conductivity
caused by condensation may also occur.
• Pollution severity level 3
Conductive pollution or dry, non-conductive pollution that can become conductive
due to condensation is likely to occur.
• Pollution severity level 4
The contamination leads to continual conductivity which can be caused by such
contaminants as conductive dust, rain or snow.
R
Rated voltage
Relative humidity
RoHS
Specified by the insulation coordination – the rated voltage is the voltage level at
which the product can be safely operated, in relation to the corresponding pollution
severity level and the surge voltage category.
The relationship between the actual moisture and the maximum possible quantity of
water in the air. Expressed as a percentage.
The EC directive 2002/95/EC – concerning the restriction of the use of certain
hazardous substances in electrical and electronic equipment – regulates the use
of hazardous materials within devices and components. This directive, and it’s
various implementations into national laws, are referred to by the abbreviation RoHS
(Restriction of Hazardous Substances).
W
W.35