This standard specifies the grades of various micro-climate conditions that the internal components (basic parts, components and built-in equipment) may encounter when the product is used under the climatic conditions of GB 4798.3 or GB 4798.4. The characteristic parameters of the microclimate are high air temperature and low relative temperature. Other climate parameters such as low temperature may also have additional effects on components, but this standard does not consider them. Considering the representative extreme high temperature, a limited number of microclimate grades are specified. Users of this standard should select the lowest grade adequate for the intended use.
GB/T 4798.9-1997 history
2012GB/T 4798.9-2012 Classification of environmental conditions.Classification of groups of environmental parameters and their severities.Microclimates inside products
1997GB/T 4798.9-1997 Environmental conditions existing in application of electric and electronic products--Microclimates inside products