This standard applies to the classification of environmental parameter groups and their severity levels encountered by products for fixed use on the ground during normal use (including installation, shutdown and maintenance, etc.). This standard includes products installed in weather-protected places for temporary or permanent fixed use, such as closed and sheltered places on land, seaside. Products on and in vehicles are not included. This standard specifies environmental conditions that are limited to those that directly affect product performance. Only environmental conditions of this type are considered. The impact of these environmental conditions on the product is not described. Environmental conditions caused by fire, explosion and ionizing radiation and other unexpected accidental accidents are not considered. In special cases, the probability of these factors occurring should be considered. The microclimate inside the product is not included. Fixed use in places without weather protection, portable and non-fixed use, vehicle and ship use, storage and transportation conditions, and microclimate inside the product are specified in other parts of GB/T4798. A limited number of environmental condition levels cover a wide range of applications. Users of this standard should choose the lowest level that covers the expected use conditions. GB/T 4798.3-2007 Environmental conditions for application of electric and electronic products Part 3: Fixed use in weather-protected locations GB/T4798.3-2007 standard download decompression password: www.bzxz.net
This part applies to the classification of environmental parameter groups and their severity levels encountered by products for ground-fixed use during normal use (including installation, shutdown and maintenance, etc.). This part includes products installed in weather-protected locations for temporary or permanent fixed use, such as closed and sheltered locations on land, seaside. Does not include products on and in vehicles. This part specifies environmental conditions that are limited to those that directly affect product performance. Only environmental conditions of this type are considered. The impact of these environmental conditions on the product is not described. Environmental conditions caused by fire, explosion and ionizing radiation and other unexpected accidental accidents are not considered. In special cases, the probability of these factors occurring should be considered. Does not include the microclimate inside the product. Fixed use in non-weather-protected locations, portable and non-fixed use, vehicle and ship use, storage and transport conditions, and the microclimate inside the product are specified in other parts of GB/T 4798. A limited number of environmental condition levels cover a wide range of applications. Users of this standard should select the lowest level that covers the expected use conditions.
class="f14" style="padding-top:10px; padding-left:12px; padding-bottom:10px;"> GB/T4798 "Environmental conditions for the application of electric and electronic products" includes:
GB/T4798.1-2005 Environmental conditions for the application of electric and electronic products Part 1: Storage
GB/T4798.2-1996 Environmental conditions for the application of electric and electronic products Transport
GB/T4798.3-2007 Environmental conditions for the application of electric and electronic products Part 3: Stationary use in weather-protected places
GB/T4798.4-2007 Environmental conditions for the application of electric and electronic products Part 4: Stationary use in places without weather protection
GB/T4798.5-2007 Environmental conditions for the application of electric and electronic products Part 5: Use on ground vehicles
GB/T4798.6-1996 Environmental conditions for application of electric and electronic products - Shipboard
GB/T4798.7-2007 Environmental conditions for application of electric and electronic products - Part 7: Portable and non-stationary use
GB/T4798.9-1997 Environmental conditions for application of electric and electronic products - Microclimate inside the product
GB/T4798.10-1991 Environmental conditions for application of electric and electronic products Introduction
This part is GB/T4798.3-2007, modified to adopt IEC60721-3-3:2002 "Classification of environmental conditions - Part 3: Classification of environmental parameter groups and their severity - Section 3: Fixed use in weather-protected locations" (English version).
This part is redrafted based on IEC60721-3-3:2002. Appendix G lists the comparison table between the chapter and article numbers of this part and those of IEC60721-3-3:2002.
Taking into account the national conditions of China, this part has been modified when adopting IEC60721-3-3:2002. The technical and editorial differences have been incorporated into the text and marked with vertical lines in the margins of the clauses to which they refer. A list of these technical and editorial differences and their reasons is given in Appendix H for reference.
The main differences between this part and IEC60721-3-3:2002 are as follows:
---Delete the foreword of IEC60721-3-3:2002;
---Add the foreword of national standard;
---Delete the definitions in Chapter 3;||tt ||
---Add 3K5L and 3K6L grades and corresponding climatological diagrams;
---Add Appendix F, Appendix G and Appendix H.
This part is a revision of GB/T4798.3-1990. The main differences from GB/T4798.3-1990 are as follows:
--- Delete the terms in Chapter 3;
--- Add Table 7 Environmental level combination, Table 8 Flashover time, Table 9 Thermal conditions before flashover, Table 10 Thermal conditions after flashover, Table 11 Visibility conditions through smoke, Table 12 Chemically active substances conditions, and the corresponding instructions in the appendix;
--- Extend the upper and lower limits of the frequency of the I and II spectra in the typical impulse response spectrum;
--- Add Appendix D, Appendix E, Appendix F, Appendix G and Appendix H.
GB/T4798 is one of the series of standards for environmental conditions of electrical and electronic products. The following gives the expected structure of these national standards and their corresponding international standards and the national standards to be replaced.
a) GB/T4796-2001 Classification of environmental parameters for electric and electronic products and their severity classification (IEC60721-1:1990, replacing GB/T4796-1984)
b) GB/T4797.1-2005 Natural environmental conditions for electric and electronic products - temperature and humidity (IEC60721-2-1:2002, replacing GB/T4797.1-1984)
c) GB/T4797.2-2005 Natural environmental conditions for electric and electronic products - altitude and air pressure, water depth and water pressure (IEC60721-2-3:1987, replacing GB/T4797.2-1986)
d) GB/T4797.3-1986 Natural environmental conditions for electrical and electronic products Biology (IEC60721-2-7)
e) GB/T4797.4-1989 Natural environmental conditions for electrical and electronic products Solar radiation and temperature (IEC60721-2-4:2002)
f) GB/T4797.5-1992 Natural environmental conditions for electrical and electronic products Precipitation and wind (IEC60721-2-2:1988)
g) GB/T4797.6-2001 Natural environmental conditions for electric and electronic products Dust, sand and salt spray (IEC60721-2-5:1991)
h) GB/T4798.1-2005 Environmental conditions for application of electric and electronic products Part 1: Storage (IEC60721-3-1:1997, replacing GB/T4798.1-1986)
i) GB/T4798.2-1996 Environmental conditions for application of electric and electronic products Transportation (IEC60721-3-2:1985, Amendment 1:1991, Amendment 2:1993)
j) GB/T4798.3-2007 Environmental conditions for application of electric and electronic products Part 3:
k) GB/T4798.4-2007 Environmental conditions for electric and electronic products Part 4: Stationary use in places without weather protection (IEC60721-3-4:1995, replacing GB/T4798.4-1990) l) GB/T4798.5-2007 Environmental conditions for electric and electronic products Part 5 :
Use in ground vehicles (IEC60721-3-5:1997, replacing GB/T4798.5-1987) m) GB/T4798.6-1996 Environmental conditions for electric and electronic products for marine use (IEC60721-3-6:1987, Amendment 1) n
) GB/T 4798.7-2007 Environmental conditions for application of electric and electronic products Part 7: Portable and non-stationary use
(IEC60721-3-7:2002, replaces GB/T4798.7-1987)
o) GB/T4798.9-1997 Environmental conditions for application of electric and electronic products Microclimate inside the product (IEC60721-3-9:
1993) p) GB/T4798.10-2006 Introduction to environmental conditions for application of electric and electronic products (IEC60721-3-0:2002, Amendment 1)
q) GB/T11804-2005 Terminology of Environmental Conditions for Application of Electrical and Electronic Products (Replacing GB/T11804-1984)
Appendices A, B, C, D, E, F, G and H of this part are informative appendices. This
part is proposed by China Electrical Equipment Industry Association. This part
is under the jurisdiction of National Technical Committee for Standardization of Environmental Conditions and Environmental Testing for Electrical and Electronic Products (SAC/TC8).
Drafting units of this part: Standard and Metrology Research Institute of the Ministry of Railways, National Railway Weighing and Weighing Station.
Main drafters of this part: Zhang Yibing, Lu Lin, Li Jianying, Qian Yuelei.
The previous versions of the standards replaced by this part are:
--- GB/T4798.3-1990.

Foreword I
1 Scope 1
2 Normative references 1
3 General requirements 1
4 Classification of environmental parameter groups and classification of their severity 2
5 Combination of environmental condition levels 3
Appendix A (Informative Appendix) Description of conditions affecting the selection of environmental parameters and severity 9
Appendix B (Informative Appendix) Climate diagrams 21
Appendix C (Informative Appendix) Application examples 28
Appendix D (Informative Appendix) Description of combined environmental conditions 30
Appendix E (Informative Appendix) Description of environmental conditions in tropical areas specified by 3K9 and 3K10 levels 31
Appendix F (Informative Appendix) Comparison table of climate types in national standards and IEC standards 33
Appendix G (Informative Appendix) Comparison of chapter and article numbers between this part and IEC60721?3?3:2002 34
Appendix H (Informative Appendix) Technical and editorial differences between this part and IEC60721?3?3:2002 and their causes 35

ICS 19.04/20
National Standard of the People's Republic of China
GB/T4798.3—2007
Replaces GB/T4798.3—1999
Environmental conditions existing in the application of electric and electronic products
Part 3:Stationary use at weather-protected locations(IEC 60721-3-3:2002.Classification of environmental conditionsPart 3:Classification of groups of environmental parameters and their severities-Section 3:stationary use at weather protectedlocations, Mo)
2007-07-13 Issued
General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China Standardization Administration of China
2008-03-01 Implementation
GB/T4798.3—2007
Normative specification
General requirements
Classification of environmental parameters and their severity levels
Appendix A (informative appendix)
Appendix B (informative appendix)
Appendix (informative appendix)
Conditions affecting the selection of environmental parameters and severity levels
Apply Application examples
Appendix D (informative appendix) Description of environmental conditions Informative appendix
Appendix (informative appendix)
Appendix (water resources appendix)
Appendix H (informative appendix)
Comparison table of climate types between national standards and IEC standards...Comparison of chapter and article numbers of this part with IC6072133:2002 Comparison of chapter and article numbers of this part with IEC60721-3-3:2002 Technical differences and abbreviations Differences and their origins CB/4798 Environmental conditions for electric and electronic products (Part 1) [2005] Part 1 of the Environmental Protection Standards for the Production of Electrical and Electronic Products; 4798.2 19a6
Environmental conditions for application of electric and electronic products for transport GB/T 4798.3—2007
G3/7 1798, 3—2007
7Environmental conditions for electric and electronic products Part 3: Environmental conditions for pressure-sensitive electronic products in protected locations Part 4: Environmental conditions for pressure-sensitive electronic products in protected locations GB/4798.4 2007
GB/- 4798, 5—2007
Environmental conditions for electric and electronic products Part 5: Environmental conditions for pressure-sensitive electronic products in electric vehicles for marine use
GB/74798.6 13961
GB/7 4798.7-2007E
Environmental conditions for electrical and electronic products Part 7: Portable and non-standard environmental conditions GB/T 4798.8-1097 Environmental conditions for use after production Microclimate GB/T 4798.1913S1 Environmental conditions for electrical and electronic products: Introduction This part is CB/T 1738.3-2007. Modification of IEC6072133:2092 Classification of environmental conditions Part 3: Classification of environmental parameters and severity levels Section 3: Climatic protection sites (English version) This part is based on [EC: 6073189120:% re-starting, and Appendix G lists the comparison table of the chapter and article numbers of this part and the chapter and article numbers of IEC6072193:2102.
Taking into account the current national conditions, the 1FC 90721-3-32002 is adopted. This part has been modified. The technical differences and general differences have been compiled into the main text and marked with vertical lines in the blank space after the clauses they are related to. A table of these technical and abbreviation differences and their reasons is given in the appendix for reference. The main differences between this part and IFC 6972138:2092 are as follows: Excluding the foreword of IEL60721-3-3;2002: - Adding the foreword of national international standards:
Delete Chapter 1 Definitions!
Add 3K5L.3kL. level without corresponding climate diagrams: add Appendix G and Appendix,
This part is the revision of GB/1 4798.31990, which is different from GB/T 4755.31990 as follows: Remove Section 9 Terminology:
Add Table 7 Flashover Grade Combination, Table 8 Flashover Time, Table Thermal Conditions Before Flashover, Table Thermal Conditions After Flashover, Table 11 Visible Conditions Through Mist, Table 12 Chemical Activity Conditions, and the corresponding instructions in the appendix; Figure 10 of typical flash spectrum, upper and lower limits of the spectrum are added to Appendix D, Appendix E, Appendix F, Appendix G GB/T 4798 and Appendix Hc are part of a series of standards for environmental conditions for electrical and electronic products: The following gives the expected structure of these national standards and the corresponding international standards and national standards that will be replaced. a) GB/T 4797-2001 Classification of environmental parameters for electrical products and their severity levels (IEC 60721-1: 1350, replacing GB/T 1795-1984)
l) GB/4797.126 Temperature and humidity of electrical products for natural environmental conditions 1FC69721-2-1: 2002. Replaces GB/T 1797.118813
c) GB/T 4797.22005 Natural environmental conditions for electronic products - altitude and air, water pressure and humidity (IEC 60721-2-3: 1987. Replaces GB/T 4797, 2—1986)d）GB/T 1737.3—956 Natural environmental conditions for electrical and electronic products: Biological (IEC 60721-2-7)..comCB/T 4798.3—2007GP/T4707.413S91 Natural environmental conditions for electrical and electronic products: Solar radiation and temperature (IEC 60721-2-4:2002)GB/T4737.5—1992 Natural environmental conditions for electrical and electronic products: Precipitation and wind01E8072131988GP/T 4767.6 2001 Natural environmental conditions for electrical and electronic products: Sand and salt spray (IEC 60721-2-511GB/ 1798, 1—2005
Electrical engineering - Environmental conditions for application of electrical products - Part 1: Storage (IEC60721$1:1997, h)
Replaces GB/T 4798.11986)
GB/T 1798.2—1996 - Environmental conditions for application of products in transport (IFC 6172[-3-2, 1985, revision: 1931. Revision 2: 19930
Product application environment - Part 1: Storage (IEC 60721$1:1997, h)
Replaces GB/T 4798.11986)
GB/T 1798.2—1996 - Environmental conditions for application of products in transport (IFC 6172[-3-2, 1985, revision: 1931. Revision 2: 19930
Product application environment - Part 1: Gas-free places - GB/T 173 3007
(IEC t0721 3 3:002. Replaces GB/T 4738, 3—1390) GB/T1798.4—2007 Environmental conditions for application of electrical products Part 1: Use in airtight locations (IEC 0721-3-4:1SS5, replaces GP/T 4768.4 1:99) 1) GB/T 4798.5 2907 Electrical 1. Electrical hand-held film bad conditions Part 5, abandoned, and used in vehicles (IEC 721-3-5:1957. Replaces GP/T 4738.5 1S87) m) G1B/T1798.6—1336 Electrical products for use in pressure-sensitive environments (IFC807216:1987, Amendment 1) GB/T 4798. 7—2007
Environmental components for electrical and electronic products, Part 7: Environmental and non-standard pressure (IFC 6721-3-7: 2002, replaced by GB/T 1798, 7—[987) GB/T4793.91997 Environmental conditions for application of electrical and electronic products Micro-gas inside the product (IE039721-3-S: 1933) || tt || B/T 4738.10-3006 Introduction to the application environment of electrical and electronic products (1EC072129: 200 Amendment 1) GB/T [[801-2015 Terminology for application conditions of products (substitutes) GB/T [[S01-1981 Appendix A, Appendix B, Appendix D, Appendix E, Appendix F, Appendix G, Appendix IT This part is the appendix of the data column. This part is proposed by China Association of Electrical and Electronic Products. This part is drafted by the National Technical Committee for Environmental Testing of Electrical and Electronic Products (China). This part is drafted by: Standard Metrology Research Institute of the Ministry of Railways, Yuejiamin Road Hengwei Metrology Station. The main contributors of this part are: Zhang Bing Lusen, Li Jianying, Qian Yuelei, and the history of the standards represented by this part is: O137T 4798, 3-1990.
..com1 Scope
Environmental conditions for application of electrical and electronic products
Part 3: Fixed use in weather-protected places CB/T 4798.3—2007
This part applies to the classification of environmental parameter groups and their severity levels during normal use (including installation, shutdown and maintenance, etc.) of products for fixed use on the ground.
This part includes products installed in weather-protected places for temporary or permanent fixed use, such as closed and sheltered places on land, seaside. Products on and in vehicles are not included. This part specifies environmental conditions that only directly affect the performance of the product. Only this type of environmental conditions are considered. The impact of these environmental conditions on the product is not described. Environmental conditions caused by fire blasting and shooting and other natural causes are not considered. In special cases, the probability of these factors occurring should be considered. The microclimate inside the product is not included.
Fixed use in places without weather protection, portable and non-fixed use, vehicle and ship use, storage and transportation conditions, and the microclimate inside the product are not included in other provisions of CB/T4798 Part of the provisions. A limited number of environmental condition levels cover a wide range of applications. Users of this part should select the lowest level that covers the expected use conditions.
2 Normative references
The clauses in the following documents become the case of this part through reference to this part of GB/T4798. For any referenced document with a date, all subsequent amendments (excluding errata) or revisions are not applicable to this part, however, parties to an agreement based on this part are encouraged to study whether the latest versions of these documents can be used. For any undated referenced document, the latest version applies to this part.
GB/T4796—2001 Classification of environmental parameters and severity classification of electrical and electronic products (IEC60721-1:1990) GB/T4797.1—2005 Temperature and humidity of natural environmental conditions for electrical and electronic products (IEC60721-2-1:2002MOD) GB/T 4798.10-2006 Introduction to environmental conditions for the application of electric and electronic products (IEC 60721-3-0; 2002, IDT) GB/F11804-2005 Terminology for environmental conditions of electric and electronic products IS0/EC Guide 52.1990 Fire terms and definitions IEC60721-2-8:1994 Classification of environmental conditions Part 2: Natural environmental conditions Section 8: Alternative fire 3 General requirements
This part is used in conjunction with GB/T1798.10-1991; the terms and definitions established in GB/T11804-20052 apply to this part. 1 Installation is usually stopped, and users of the standard should distinguish such conditions from the use of the product. Unless otherwise specified, the leakage level should be selected at this time.
The probability of exceeding the specified severity is very low, and all specified values ​​are maximum or limit values. These values ​​may be reached, but will not appear for a long time. The frequency of occurrence of severity varies over a period of time in different locations. This standard does not consider such frequency, but the frequency of occurrence of any environmental parameter should be considered. If necessary, additional provisions will be made. The frequency and period of occurrence are specified in GB/T4798.10-2006.
It should be noted that the simultaneous occurrence of several specified environmental parameters may increase the impact on the product. When biological conditions, chemically active substances, and mechanically active substances conditions occur at the same time with high relative humidity, the environmental conditions of a certain location may be affected by other factors, such as heat sources, special process conditions, etc. The measurement of environmental conditions at a certain location should be carried out at selected points around the product. It should be recognized that extreme and special environmental conditions exist. Products used in such special environments shall be determined by negotiation between the supplier and the screener. 4 Classification of environmental alternative groups and their severity classification Tables 1 to 6, 8 to 12 specify a series of environmental condition levels: climatic conditions (K)
special climatic conditions (Z)
biological conditions (B)
chemically active substance conditions (C)
mechanically active substance conditions (S);
mechanical conditions (M):
initial conditions for ignition (T, P, F, V, H>.
The possible environmental condition combinations that the product may be exposed to constitute a series of categories, representing the actual situation of the world-wide application, depending on the outdoor climate, building structure, installation, process conditions, etc. The higher numerical environmental condition levels usually include the lower numerical environmental condition levels. Some parameters cannot quantitatively specify the severity. degree. For a given location and product, a complete set of grade combinations should be selected, such as: 3K2/3Z1/3Z4/3B1/3C2/3S1/3M4 and 3T1/3P3/3F2/3V2/3H3. Appendix A explains the basis for the environmental condition grades, describes the use sites included in each grade, and gives the circumstances that affect the selection of environmental parameters and their severity.
Xie Lu Lu B gives a diagram of the relationship between air temperature, relative humidity and absolute humidity in the climate grades specified in Table 1. Appendix C gives two examples of the application of environmental parameter classification. 4.1 Climate conditions
The climate conditions specified in 31 to 3K8 represent the environmental conditions for climate protection sites. They are the environmental conditions experienced over a long period of time within the country, taking into account all parameters that can affect them. The conditions take into account factors such as external (outdoor) climatic conditions, building structure type, temperature/humidity control system and internal conditions (such as heat dissipation of installed equipment, human activities, etc.). These conditions take into account all normal situations, but do not include special cases, such as failure of air conditioning systems.
3K9 and 3K10 specify climatic conditions for tropical areas, which are explained in Appendix E. When choosing the appropriate level, it should be noted that the climatic conditions inside the building depend on the external (outdoor) conditions, especially the air, solar radiation and building structure type. Walls with good heat trapping ability or high heat capacity can continuously balance the temperature changes during the day and even longer. Walls with poor insulation ability do not have this effect. Instead, the temperature difference is magnified due to solar radiation during the day and heat dissipation of the building at night. Effect of solar radiation The result is increased by the canal heating effect and the greenhouse effect. The actual relationship between temperature and humidity cannot be expressed in terms of severity alone. Therefore, a climate diagram is given in Appendix B. 4.2 Special climatic conditions
Various degrees of thermal radiation, ambient air movement, other water sources other than rain, high temperature and low pressure can be accompanied by other climatic conditions. Table 2 specifies these special environmental conditions. In this case, several events occurring simultaneously will increase the severity, and considering these will lead to unnecessary design.
4.3 Biological conditions
These conditions cannot be specified by law. The special parameters in Table 3 are typical, but not necessarily complete. 4.4 Chemically active substances
Pollution from the environment mainly comes from industrial activities, motor vehicles and the exhaust effect of mining systems. More serious chemical pollution comes from sea salt. These pollutants may affect the material properties of the product. CB/T 4798.3-2007
The indicators given in the classification are based on several years of investigation. Since the direct impact of high concentrations in the short term can lead to more serious damage to materials or even make them irregenerative, the maximum values ​​are given in the table. The average values ​​are given in the appendix because they play an important role in the long-term impact on the internal components of the product. In fact, it is impossible for all pollutants in this section to appear at the same time. Even if these pollutants appear at the same time, the possibility of their concentrations being uniform at the same time is not great. In places with different concentrations, usually only one pollutant has a high concentration. The specified values ​​of level 3C1 correspond to rural areas and areas with low industrial activities. The specified values ​​of level 3C2 correspond to urban areas. Therefore, the severity of these two levels meets the results of the combined effect of all parameters. The severity of levels 3C3 and 3C1 cannot be considered to meet the results of the combined effect of all parameters.Otherwise it will lead to uneconomical over-design. For 3G3 and 3C4 grades, only a single parameter corresponding to the place of use can be selected. If a single parameter in 3C3 and 3G4 grades is selected, the other parameters not mentioned can be selected from the numerical method in 3C2 grade: chemically active coatings and chemically active substances other than free salt are not considered in this part. 4.5 Mechanically active substances
Sand and raw materials are taken as the same environmental parameters because their effects are similar. 4.6 Mechanical conditions
Sinusoidal vibration is classified according to the mechanical values ​​of acceleration and displacement, corresponding to different frequency ranges. Random vibration is not considered in this part + it will be considered when sufficient data is available. Unsteady vibration including shock is classified according to the first level undamped maximum shock response spectrum, see GB/T4796-2001. 4.7 Fire initial state case
Fire environmental conditions See IEC60721-2-8:1994, which is related to the initial state of fire in the air, and is the basis for selecting environmental parameters and their severity levels. The main parameters are as follows:
a) Fire conditions before flashover:
Flashover time (see Table 8)
- Heat energy requirements for various surfaces and objects in the place:
The upper gas temperature in the place;
The heat release efficiency (RHR), which is related to the heat release rate in the place that causes flashover (RHRfo), and is therefore expressed as the ratio RHR/RHRf (see Table 9).
Fire conditions after flashover:
The highest gas temperature, which occurs during the heat removal stage of the fire place (see Table 10). Smoke and chemically active substances conditions:
-Optical density (see Table 11);
-Hydrogen chloride spot (see Table 12).
The listed parameters are used to describe the environmental fire history conditions. Some parameters specify the characteristics of the fire. The levels in Table 9 are the reaction of materials and products to fire under fire conditions before flashover, and the parameters corresponding to the levels in Table 10 are the fire properties and fire resistance of load bearing, discrete structures, windows, ventilation systems, etc. after flashover fire conditions. Although there are no direct fire characteristics specified, the heat release rate parameters in Table 9 and the time parameters in Table 8 are extremely important for flashover hazards and for people to escape the fire safely if flashover occurs. The gas temperature parameters in Table 9 and the parameters in Tables 11 and 12 are fire characteristics, which are very important for optical instrument detection, escape during evacuation, and shelter in safe areas during fire. The concentration of hydrogen chloride generated by electrical products after fire is extremely important for evaluating the subsequent corrosion of the product. 5 Environmental condition level combination
An environmental condition group consists of a series of possible combinations of product environmental conditions. The number and flexibility of combinations are very large. In practice, this flexibility is not always beneficial, for example, when different parties negotiate environmental condition documents, there will inevitably be minor differences that are disturbing. In general, in order to avoid this possibility, a standard combination of strict levels is selected from the table. For the specified places and products, refer to this part, for example, select IE32. Only when the standard does not include the severity level combination, the level combination can be selected according to each level in this part. If the severity of some parameters is different from the level combination specified in this part, the following phrase should be added to indicate: "But. (See GB/T 4798.3-2007
number)--.. (severity and unit)", for example IE 32 but sand is 30 mg/m3. Appendix D Description of combined environmental conditions
Table 1 Climate condition levels
Environmental parameters
Low relative humidity
Common relative humidity
Low relative humidity
Common absolute humidity
Temperature change rate
Low positive air
Solar radiation
Thermal radiation
Around the country, air movement"
Comfortable conditions
Snow and water conditions (rain, snow, etc.)
Other than scattered rain
Icing conditions
i/tain
Temperature change rate (E min) The average value of time does not include the miscellaneous work of the mine.
For air-conditioned places, the temperature deviation is 2 of the specified value. 3KS
3K63K6L
The non-assisted convection refrigeration system may be disturbed by the reverse flow of the surrounding air. In special cases, it can be selected from Table 2. The conditions of the corresponding places are selected from Table 2.
3K7L3K83K8H3K8L3K9310h
70kPa The severe longitude value is suitable for applications in the whole world (corresponding to an altitude of 3 000 m). For some restricted use places, it can be selected from Table 2. More information on the 3K9 (tropical humid heat) and 3K10 (tropical dry heat) classes is given in Appendix E. Table 2 Classes of special climatic conditions
Environmental parameters
Low pressure
Thermal radiation
Special conditions
Negligible
There are thermal radiation conditions. For example, there are thermal radiation conditions near indoor heating systems. For example, there are thermal radiation conditions near indoor heating systems or industrial furnaces, commercial furnaces Environmental parameters
Air movement
Other water sources other than rain
Table 2 (continued)
Unassisted convection cooling systems may be disturbed by the reverse movement of the surrounding air. a
Does not include underwater conditions.
Class 3212 corresponds to about 1 400 m sea disturbance height. Table 3 Biological condition level Environmental parameters Hydrogen sulfide Hydrogen fluoride Hydrogen fluoride, fungi, etc. Rodents and other animals that endanger products, mosquitoes Special conditions outside the environment Dripping conditions Dripping conditions Dripping conditions Dripping conditions Dripping miscellaneous items GB/T 4798.32007
Shunyin, real chisel, etc.
Rodents or other animals that endanger the product, including white effect Table 4 Chemically active substances Condition level
ern'/m*
Maximum value
Maximum value
Maximum value
Average value Sensitivity
Average value
Average value Maximum value
Maximum value
With salt spray
With salt spray
GB/T 4798.3—2007
Environmental parameters
Hydrogen (oxygen
Hydrogen equivalent
expressed)
Maximum value
Maximum value
Table 4 (continued)
Maximum value
Average value
Maximum value
Average value
Maximum value
The corresponding values ​​in cm/m are derived from the corresponding values ​​in mg/m*, and the adjusted values ​​in the table are calculated under the reference environment of 20 and 101.3 kPa. The average value should be the long-term value. The maximum value is the limit value or peak value, which does not exceed 30 min per day. The 3C3 and 3C4 levels are not considered as the comprehensive effects of all parameters. If necessary, parameters can be selected in the 3C3 and 3C4 levels. At this time, other parameters are determined according to the 9C2-level.
Salt spray may appear in offshore and coastal sheltered places. Table 5
Environmental parameters
Dust (floating)
Dust (deposition)
Environmental parameters
Sinusoidal steady-state excitation
Frequency range
Non-state vibration, including
shock (see Figure 1)
Shock response spectrum L
Acceleration peak value
Shock response spectrum I
Acceleration peak value a
Shock response harmonic II
Additional degree peak value
Mechanically active material condition level
Table 6 Mechanical conditions Component level
Environmental conditions
Special climate
Chemically active substances
Mechanically active substances
Environmental parameters
Flashover time
Environmental parameters
Heat flux to which materials and products are subjected
Gas temperature (upper layer of gas)
Environmental level combination
Grade combination
Table 8 Flashover time
Thermal conditions before flashover
Ratio of heat release rate to heat drying efficiency causing flashover
Thermal conditions after flashover
Environmental parameters
Gas temperature
Hot duration
Environmental parameters
Optical density
Visibility conditions through smoke
Note: See IEC 60721-2.8:1994 Explanation of Figure 13 3V2
Table 12 Chemically active substances conditions
Environmental parameters
Hydrogen oxide concentration
Duration
GB/T 4798.3—2007
GB/T4798.3-2007
Example of half-sine pulse duration
Spectrum I: duration 22 ms;
Spectrum 1: duration 11 ms;
Spectrum: duration 6
Figure 1 Typical impulse response spectrumwww.bzxz.net
(First level maximum impulse response spectrum)
Frequency/Hz
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