IEC/TR 60664-2-1:20 11是一份技术报告，是技术委员会和制造商的应用指南，它们根据IEC 60664系列规定了产品的尺寸要求。主要考虑事项如下: a)标称系统电压或额定绝缘电压； b)产品的过电压类别(OV cat.)； c)任何类型的过电压； d)电压的频率； e)固体绝缘材料的特性； f)污染程度和湿度水平。 与上一版相比的主要变化如下: -先前版本仅为IEC 60664-1的应用指南。第二版不仅考虑了IEC 60664-1，还考虑了其他部分IEC 60664-3、IEC 60664-4和IEC 60664-5及其相互关系； -解释了IEC 60664系列用于低压设备绝缘尺寸的原理，并提供了实际应用的示例以及一些背景信息； -附件A概述了IEC 60664-1中要求技术委员会做出决定或规定选项或要求制造商开展活动的条款； -附录B概述了IEC 60664-4的此类条款； -附录C概述了IEC 60664-5的此类条款； -附录D修订了IEC 60664-1:20 07附录F的表格，其中规定了从标称直流得出的线路至中性线电压的额定冲击电压。电压高达1 500 V（含1 500 V）。 根据IEC指南104具有基本安全出版物的状态。 2011年10月更正的内容已纳入本副本。

IEC/TR 60664-2-1:2011, which is a technical report, serves as an application guide for technical committees and manufacturers specifying dimensioning requirements for products in accordance with the IEC 60664 series. The significant items for consideration are as follows:
a) nominal system voltage(s) or rated insulation voltage(s);
b) overvoltage category of the products (OV cat.);
c) any type of overvoltages;
d) frequency of the voltage;
e) characteristics of the solid insulating material;
f) pollution degree and humidity levels.
The main changes with respect to the previous edition are listed below:
- the previous edition was only an application guide for IEC 60664-1. This second edition takes into account not only IEC 60664-1 but also the other parts IEC 60664-3, IEC 60664-4, and IEC 60664-5 and their interrelation;
- principles of the IEC 60664 series for insulation dimensioning of LV equipment are explained and examples of practical application are provided together with some background information;
- Annex A provides an overview of clauses of IEC 60664-1 requiring decisions by technical committees, or specification of options, or requiring activities of the manufacturer;
- Annex B provides an overview of such clauses of IEC 60664-4;
- Annex C provides an overview of such clauses of IEC 60664-5;
- Annex D amends the tables of Annex F of IEC 60664-1:2007 with rated impulse voltages for voltages line to neutral derived from nominal d.c. voltages up to and including 1 500 V.
Has the status of a basic safety publication in accordance with IEC Guide 104. The contents of the corrigendum of October 2011 have been included in this copy.