GB/T 4797.1-1984 Temperature and humidity of natural environment conditions for electrical and electronic products GB/T4797.1-1984 Standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Natural Environmental Conditions of Electric and Electronic Products
Temperature and Humidity
Environmental conditions appearing in natureof electric and electronic productsTem perature and humidity
UDC 621.3:620
GB 4797.1-84
This standard proposes the outdoor climate types expressed by temperature and humidity parameters in my country as background material for selecting appropriate temperature and humidity severity levels when applying products.
These climate types include all regions of my country except plateau areas with an altitude of more than 5,000 meters. This standard can also be used as background material when determining the environmental conditions for product application. When selecting the severity level of temperature and humidity for the product application standard, the values ​​listed in GB4796-84 "Classification of Environmental Parameters for Electric and Electronic Products and Their Severity Grading" must be used. 2
Determine the types of outdoor climates expressed by temperature and humidity parameters so as to satisfactorily represent the environmental conditions that the product often encounters during transportation, storage, installation and use.
Electricity"Electricity Since the product is used in almost all climatic conditions in my country, the product should be able to withstand the impact of adverse climatic environments, which requires the detailed information of the climatic conditions that the product will encounter to be mastered in advance during the design stage. Ba has collected and statistically analyzed the outdoor temperature and humidity data from 1961 to 1980 across the country, which can be easily represented by climate charts.
In addition to the outdoor temperature, the temperature impact on a product is also related to many other environmental parameters. For example, solar radiation, wind speed, heating of adjacent equipment, etc.
The impact of humidity depends on factors such as temperature, humidity changes and impurities in humid air. In many cases, the temperature and humidity extremes that appear for a short time in a day are very important. In other cases where the product thermal time constant is relatively large or there is water vapor penetration, the half-mean of temperature and humidity in a period may be more important. For this purpose, two average values ​​are used: one is the average value of the annual extreme values ​​of temperature and humidity that only occur in a short period of time (a few hours), and the other is the average value of the annual extreme values ​​of the daily average values ​​of temperature and humidity that occur in a longer period of time. In order to take into account the extremely rare cases, the absolute extreme values ​​of temperature and humidity observed over many years must also be given. This standard does not consider the reliability issues, but only gives the extreme values ​​of temperature and humidity and their combined values. In order to study the reliability issues, it is also necessary to master the entire statistical distribution data of temperature and humidity. This information is also needed when considering the diffusion of water vapor through materials.
Expression of statistical data on temperature and humidity 4.1 Statistical outdoor climate types
Issued by the National Bureau of Standards in 1984-1224
Implemented in 1985-0701
GB4797.1-84
In order to use a product in a limited local geographical area, it is necessary to find the outdoor temperature and humidity values ​​from the statistical climate map of the area, and design the product based on these data so that the product can work normally in this type of climate environment. This standard specifies six climate types suitable for my country's situation (hereinafter referred to as "statistical outdoor climate") based on different outdoor temperature and humidity conditions within the national scope.
4.2 Statistical outdoor climate groups
In order to enable a product to be used in geographical areas with different climate types in my country, the statistical outdoor climate can be appropriately merged into the main climate groups.
The purpose of merging into three climate groups is to limit the classification of temperature and humidity so that the product can be used in a wider range. Description of statistical outdoor climate
5.1 Environmental parameters
In this standard, the statistical outdoor climate is specified by the following environmental parameter values: temperature,
relative humidity.
The relative humidity at a certain temperature is determined by the ratio of the actual water vapor pressure to the saturated water vapor pressure at that temperature. Under the condition of constant air pressure, the absolute humidity of the air (the actual water content in a unit volume of air) is given by the air temperature and relative humidity.
5.2 Climate map
5.2.1 Overview
The climate map provided in this standard determines the range of six types of outdoor climate in my country. There are three boundary lines on the map. The first is the half-mean of the annual extreme value of the daily average value, the second is the average of the annual extreme value, and the third is the absolute extreme value. 5.2.2 The boundary lines representing the average of the annual extreme value of the daily average value of temperature and humidity. On the climate map, the horizontal axis represents the temperature and the vertical axis represents the relative humidity. The daily average temperature and the relative humidity that appear at the same time in a place representative of the geographical area are plotted on the map. Then the outermost points on the map are connected to obtain the boundary line representing the annual extreme value of the daily semi-mean. Then the average line of such boundary lines is taken for each year (the data period is 1961-1980), and this boundary line is slightly smoothed to make them parallel to the isovalues ​​of temperature, relative humidity and absolute humidity, and the boundary line in the climate map is obtained.
If the product is exposed for a short period of time (a few hours each time), the probability of exceeding the temperature and humidity of the boundary line and their combination is relatively high, reaching about 5%. However, if the product needs to be exposed for a long time to reach the temperature of the surrounding environment, then the product will not be affected by the temperature conditions that are more severe than the boundary line encountered during short-term exposure. 5.2.8 Limit lines representing half-means of annual extremes of temperature and humidity The same method of drawing as in subclause 5.2.2 is used to plot all the temperature and relative humidity points that occur simultaneously in a year for a particular place that is representative of the geographical area. The limits representing the annual extremes of temperature and humidity are then connected by connecting the outermost points on the map. The limit lines representing the annual extremes of temperature and humidity are then averaged for each year (data for the period 1961 to 1980) and slightly smoothed to make them parallel to the contours of temperature, relative humidity and absolute humidity to obtain the limit lines on the climate map. Although the extreme limit values ​​of temperature, relative humidity and absolute humidity read from the climate map do not accurately represent the average values ​​of the annual extreme values, for practical use of the climate map, the extreme limit values ​​read from the climate map can still be assumed to represent the average values ​​of the annual extreme values.
The probability that a product will be exposed to a combination of temperature and relative humidity outside the limit lines depends on the length of time the product is outdoors. Products that are exposed outdoors for years can be expected to encounter temperatures and combinations of temperatures and humidity that are more extreme than the limit values ​​for a short period of time.
If the product is exposed to outdoor conditions for only a short period of time, the probability that the product will encounter temperatures and humidity that are more extreme than the limit values ​​is very small.
The annual extreme low temperature value usually occurs for about 10 hours, while the annual extreme high temperature value occurs for a shorter period of time, usually about 5 hours. Therefore, from a statistical point of view, the probability of the occurrence of a low temperature extreme is about 0.1%, while the probability of the occurrence of a high temperature extreme is about 0.05%. 5.2.4 Limit lines representing absolute extremes of temperature and humidity The same drawing method as in subclause 5.2.2 is used to plot all the values ​​of temperature and relative humidity from 1961 to 1980 for a place representative of the geographical area on the map, and then connect the outermost points on the map to obtain the limit lines representing the absolute extremes of temperature and humidity.
The limit lines are slightly smoothed to make them parallel to the contour lines of air temperature, relative humidity and absolute humidity. Absolute extremes occur very rarely and for very short periods of time and are only considered in special applications. For example, effective operation of communication equipment under the most severe climatic conditions. 5.3 Statistical classification of outdoor climate
my country's outdoor climate is divided into six climate types. They are cold, cold-temperate, warm-temperate, hot, humid-hot, and humid-hot. Table 1 gives the average values ​​of the daily average values ​​of temperature and humidity for the six climate types in my country. Table 2 gives the average values ​​of the annual extreme values ​​of temperature and humidity for the six climate types in my country. Table 3 gives the absolute extreme values ​​of temperature and humidity for the six climate types in China. Appendix A shows the regional distribution of the six climate types in my country. Table 1 Daily average values ​​of various climate types Daily average temperature and humidity Annual extreme values ​​Average values ​​Climate type
Cold-temperate!
Cold temperature II
Sub-humid heat*
Climate type
Cold overflow"
Cold temperature II
Industrial humid heat
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Maximum temperature when relative humidity is 95%
Table 2 Various climate types divided by annual extreme values
Annual extreme average values ​​of temperature and humidity
Maximum temperature when relative humidity>95%
The middle value in 1 is equal to heat (the same below).
Maximum absolute humidity
Maximum absolute humidity
Climate type
Wet and hot
GB 4797.1—84
Table 3 Absolute extreme values ​​of temperature and degree for various climate types
Maximum temperature when relative humidity ≥ 95%
Maximum absolute humidity
All the data in the above table are derived from meteorological data from 1961 to 1980. Obviously, if the age of the observation data is increased, the absolute extreme values ​​of temperature and humidity in Table 3 may be larger. Figures 1 to 7 show the climate maps of the six statistical Guangwai climate types in my country (drawn with data from regional representative points). 32
Relative density
GB 4797.1--84
Figure 1 Climate diagram of cold climate type
1 - Boundary line of the average value of the daily average value of temperature and humidity and the annual extreme value, 2 - Boundary line of the average value of the annual extreme value of temperature and humidity, 3 - Boundary line of the absolute extreme value of temperature and humidity Note: The meanings of the boundary lines 1, 2, and 3 in Figures 2 to 7 are the same as above. 30
Absolute humidity (g·m㎡3)
Temperature (℃)
Relative humidity
GB 4797.1—84
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Figure 2 Climate map of cold-temperature 1 climate type
Absolute humidity (g*m3)
Temperature ()
Relative humidity
GB 4797.1—84
Figure 3 Climate map of cold-temperature Ⅱ climate type
Absolute humidity (g·m
Temperature ()
Relative humidity
GB Figure 4 Climate diagram of warm climate type
Absolute humidity (g m3)
Air temperature (C)
Relative humidity
GB 4797.1--84
Climate diagram of hot climate type
Absolute humidity (g m3)
Air temperature (C)
Relative humidity (%)
GB4797.1--84
Figure 6 Climate diagram of sub-humid hot climate type
Absolute humidity (g m-
Air temperature (C)
Relative humidity
5.4 Statistical outdoor climate groups
GB 4797.1-84
Figure 7 Climate map of humid and hot climate types
The outdoor climate statistics can be divided into the following three groups: b. Limited group: limited to warm and warm climate types; b:
General group: including cold and warm, warm, dry and hot and sub-hot climate types, General group: including six climate types in my country. C.
Absolute humidity (gm
Air temperature (℃)
Table 4 gives the temperature and humidity of the three climate groups in my country. Table 5 gives the average annual extreme values ​​of temperature and humidity in the three climate groups in my country. Table 6 gives the absolute extreme values ​​of temperature and humidity in the three climate groups in my country. 39
Limited group
·General group
General group
“Climate group
Limited group
General group
Climate groupbzxz.net
Limited group
General group
Climate group
Limited group
General group
GB 4797.1--84
Guangwai climate groups divided by daily average values
Annual extreme values ​​of daily average temperature and humidityAverage high temperature
Maximum temperature when relative condensation ≥ 95%
Table 5 Outdoor climate groups divided by annual extreme values
Annual extreme values ​​of temperature and humidityAverage values
Maximum temperature when relative humidity ≥ 95%
Table 6 Outdoor climate groups divided by absolute extreme values
Absolute extreme values ​​of temperature and humidity
Maximum temperature when relative humidity>95%
Maximum absolute humidity
g·m-3
Maximum absolute humidity
g·m-3
Maximum absolute humidity1--84
Guangwai climate groups divided by daily average values
Annual extreme values ​​of daily average temperature and humidityAverage high temperature
Maximum temperature when relative condensation ≥ 95%
Table 5 Outdoor climate groups divided by annual extreme values
Annual extreme values ​​of temperature and humidityAverage values
Maximum temperature when relative humidity ≥ 95%
Table 6 Outdoor climate groups divided by absolute extreme values
Absolute extreme values ​​of temperature and humidity
Maximum temperature when relative humidity>95%
Maximum absolute humidity
g·m-3
Maximum absolute humidity
g·m-3
Maximum absolute humidity1--84
Guangwai climate groups divided by daily average values
Annual extreme values ​​of daily average temperature and humidityAverage high temperature
Maximum temperature when relative condensation ≥ 95%
Table 5 Outdoor climate groups divided by annual extreme values
Annual extreme values ​​of temperature and humidityAverage values
Maximum temperature when relative humidity ≥ 95%
Table 6 Outdoor climate groups divided by absolute extreme values
Absolute extreme values ​​of temperature and humidity
Maximum temperature when relative humidity>95%
Maximum absolute humidity
g·m-3
Maximum absolute humidity
g·m-3
Maximum absolute humidity
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