Environmental conditions of electric products in indoor and outdoor corrosive location
1 Scope
This standard specifies the environmental conditions of the corrosion resistant electric products for indoor and outdoor use (hereinafter referred to as corrosion resistant electric products) and the severity.
This standard is applicable to corrosion resistant electric products. The environmental conditions suitable for corrosion resistant electric products may be put forward according to the severity specified in this standard.
Note: "Indoor" means weather-protected locations where the products can be completely or partially protected from direct climatic impact. "Outdoor” means non-weather-protected locations where the products cannot be protected from climatic impact.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 4796 Classification of environmental conditions of electric and electronic products - Part 1: Environmental parameters and their severities
GB/T 4797.1 Environmental conditions appearing in nature of electric and electronic products - Temperature and humidity
3 General requirements
3.1 The weather protection types used in this standard shall be as specified in GB/T 4797.1.
3.2 When designing the corrosion resistant electric products, attention shall be paid to the fact that when two or more environmental parameters act in combination, the impact on the products will be increased. It is especially significant when high relative humidity acts in combination with chemically active substances or mechanically active substances. Attention shall also be paid to the impact of other environmental factors, such as heat dissipation sources and special production processes, which occur in certain locations.
3.3 If the environmental condition grades specified in this standard cannot meet the extreme special environmental conditions, other grades specified in GB/T 4796 may be adopted through negotiation between the manufacturer and the user.
4 Classification of environmental conditions and severities
4.1 The environmental conditions are classified into the following six categories: climatic conditions (K), special climatic conditions (Z), biological conditions (B), chemically active substance conditions (C), mechanically active substance conditions (S) and mechanical conditions (M).
4.2 The severity of environmental conditions for corrosion resistant electric products shall be selected from Table 1. Grades marked with larger numbers usually include grades marked with smaller numbers (with the exception of special climatic conditions (Z)).
4.3 For the purpose of this standard, the environmental condition grade with the lowest severity that can meet the operating requirements of the products shall be selected.
4.4 For the environmental condition grades (e.g. codes 3K×, 3Z×, 3C× and 4K×, 4Z×, 4C×, etc.) specified in this standard, "3” indicates the weather-protected locations while "4" indicates the non-weather-protected locations.
4.5 The environmental condition grades for climatic conditions are shown in Tables 2 to 5.
——See Tables 2 and 3 for the environmental parameters for different grades of climatic and environmental conditions. The environmental parameters listed in the table are multi-year averages of the maximum value in each year;
——See Tables 4 and 5 for the different grades of special climatic and environmental conditions.
Foreword i
1 Scope
2 Normative references
3 General requirements
4 Classification of environmental conditions and severities
Annex A (Informative) Instructions for the grades of environmental conditions included in this standard
A.1 General
A.2 Climatic and environmental conditions
A.3 Biological environmental conditions
A.4 Environmental conditions of chemically active substances
A.5 Environmental conditions of mechanically active substances
Table 1 Severity of different environmental conditions
Table 2 Grades of climatic and environmental conditions at weather-protected locations
Table 3 Grades of climatic and environmental conditions at non-weather-protected locations
Table 4 Grades of special climatic and environmental conditions at weather-protected locations
Table 5 Grades of special climatic and environmental conditions at non-weather-protected locations
Table 6 Grades of bioenvironmental conditions at weather-protected and non-weather-protected locations
Table 7 Grades of environmental conditions with chemically reactive substances at weather-protected and non-weather-protected locationsa
Table 8 Grades of environmental conditions with mechanically active substances at weather-protected locations
Table 9 Grades of environmental conditions with mechanically active substances at non-weather-protected locations
Table A.1 Climate types specified in national standards and IEC standards
