IEC 60664-3:2016 applies to assemblies protected against pollution by the use of coating, potting or moulding, thus allowing a reduction of clearance and creepage distances as described in IEC 60664-1. This document describes the requirements and test procedures for two methods of protection:
- type 1 protection improves the microenvironment of the parts under the protection;
- type 2 protection is considered to be similar to solid insulation. This edition includes the following significant technical changes with respect to the previous edition:
a) information added concerning interpolation;
b) provided scratch test is only for type 2 protection;
c) renumbered the scratch test to follow the visual examination test, since it makes more sense there;
d) separated the tables under what is now called Annex A, to make them clearer.