低压系统内设备的绝缘配合.第3部分:防止污染的涂层、灌封或模制的使用

[中文适用范围]： This part of IEC 60664 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 micro environment of the parts under the protection; – type 2 protection is considered to be similar to solid insulation. This document also applies to all kinds of protected printed boards, including the surface of inner layers of multi-layer boards, substrates and similarly protected assemblies. In the case of multi-layer printed boards, the distances through an inner layer are covered by the requirements for solid insulation in Part 1 IEC 60664-1. This document refers only to permanent protection. It does not cover assemblies that are subjected to mechanical adjustment or repair. The principles of this standard are applicable to functional, basic, supplementary and reinforced insulation. [外文原描述]： IEC 60664-3:2016 RLV contains both the official IEC International Standard and its Redline version. The Redline version is available in English only and provides you with a quick and easy way to compare all the changes between the official IEC Standard and its previous edition. 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.