本指南规定了当测试对象的外部绝缘受到污染、冰、雪或冷雾的影响时，测试设备的程序。这些方法仅适用于额定电压高于1 kV的设备上的试验。本指南规定了当测试对象的外部绝缘受到污染、冰、雪或冷雾的影响时，测试设备的程序。这些方法仅适用于额定电压高于1 kV的设备上的试验。

The guide specifies procedures for testing equipment when external insulation of the test object is subjected to combinations of contamination, ice, snow, or cold fog. The methods are applicable only to tests on equipment with a rated voltage above 1 kV.The guide specifies procedures for testing equipment when external insulation of the test object is subjected to combinations of contamination, ice, snow, or cold fog. The methods are applicable only to tests on equipment with a rated voltage above 1 kV.