GB/T 2423.22-2002 Environmental testing for electric and electronic products Part 2: Test methods Test N: Temperature change
Some standard content:
ICS 19.040
National Standard of the People's Republic of China
GB/T 2423.222002/IEC 60068-2-14: 1984 replaces G13/T2423.221987
Environmental testing for electric and electronic productsPart 2: Test methods
Test N:Change of temperature(IEC 60068-2-14:1984.Basic environmental testing procedures-Part 2.Tcsis--Tcst N,Changc of temperature,IDr2002-06-13 Issued
People's Republic of China
State General Administration of Quality Supervision, Inspection and Quarantine
2003-01-01 Implementation
GB/T2423.22:2002/IEC:60068-2-14:1984 Foreword
This part of GB/T2123 is equivalent to IEC60068-2-14:1984 (formerly 1EC68-2-14:1984 English version) "Basic Environmental Testing Procedure Part 2: Test Method Test N: Temperature Change" and its Amendment 1:1986. For amendments, see 50B (Central Office) No. 25
The double vertical lines in this part are TFC60068-2-11:1984 Amendment This part replaces GB/T2423.22-1987 "Basic environmental testing procedures for electronic products Part 2: Test method test N: Temperature change". This part is written in GB/T2423.22-1987 with the following differences: In order to be consistent with the name of the GB/T2423 series of standards on environmental testing methods for electronic products, this part is named "Environmental testing for electronic products Part 2: Test method test N: Temperature change". The test method of GB/T2423.22-1987 is equivalent to the international standard IEC60068-214 "Basic environmental testing procedures Part 2: Test method test N: Temperature change" (1984 edition) and its amendments: 1986. In terms of writing format and expression, it is consistent with 1EC 60068-2-14:1984.
According to the provisions of the International Standards in 4.7 of G13/T1.1-2000 "Guidelines for Standardization Work Part 1: Structure and Writing Rules of Standards", "For standard texts that are equivalent to international standards, their structure should be consistent with the adopted international standards", this part is the same as IFC60068-2-14:1984 in terms of technical content, text structure and wording, writing method and sequence, etc., and this part has made some editorial changes in the format.
This part is one of the GB/T2123 series of standards for environmental test methods for electrical and electronic products. This part involves the following national standards corresponding to IEC publications:
GB/T2423.1—2001 Environmental test for electrical and electronic products Test A: Low temperature (idtIEC600#8-2-1:1990) GB/T2423.2--2001 Environmental test for electrical and electronic products Test B: High temperature (idtIEC60068-2-2:974) GI32424.13—2002 Environmental test guide for temperature change of electrical and electronic products (idIEC600682-33:1971) This part is proposed by China Electrical Equipment Industry Association. This part is under the jurisdiction of the National Technical Committee for Environmental Conditions and Environmental Tests for Electrical and Electronic Products (CSI3TS/TC89). The drafting unit of this part is Guangzhou Electrical Science Research Institute, and the drafter of this part is Zhang Qiangying.
The previous versions of the standard replaced by this part are: G3 2423.22—1981. GB2423.221987.431
GB/T 2423.22—2002/1EC 60068-2-14:1984 History of Test N: Temperature Change Test The first edition 1954 contains only one procedure, Test Na: Rapid Temperature Change, Two Chamber Method, the second edition 1560 is equivalent to the above Test Na: but the conversion time is (2~~3) min instead of 5 min. The third edition 1969 introduces:
Test Na two chamber method, equivalent to the above Test Na. The option of 30 min test duration is increased to 3 h, and the higher and lower temperatures are selected to replace the forced limits of Test A and Test B. Test Nb - chamber method.
Test Ne - two water bottle method.
The fourth edition 1974 introduces:
Test Na - Two Chamber Method, equivalent to the previous test Na, 1 adds requirements for certain chambers and includes the test of heat dissipation test samples.
Test Nc - Two Tanks Method, no changes. The fifth edition 1984 introduces:
Test Na - Rapid Temperature Change with Specified Transition Time, equivalent to the previous test Na, but the transition time given is more precisely specified and there is a longer exposure time; Test Nb - Temperature Change with Specified Rate of Change, equivalent to the previous test Nb, but the temperature change rate is specified and the factory exposure time is longer. Test Nc - Rapid Temperature Change Two Tanks Method, equivalent to the previous test Nc, but the water volume is no longer limited during the test and the duration parameters are specified more accurately. 4:2
GB/T 2423. 22 - 2002/IFC 60068-2-14:1984 Environmental testing for electric and electronic products Part 2: Test methods Test N: Temperature change The temperature change test is applicable to determining the effect of one or more consecutive temperature changes on the test sample. This test cannot be used to assess the effect caused by high or low temperature. For such effect, high temperature or low temperature test methods should be used. The main parameters affecting the temperature change test are: high and low temperature values within the temperature change range; holding time of the test sample at high and low temperatures; rate of humidity change from low temperature to high temperature or from high temperature to low temperature; number of test cycles under one condition; total heat absorbed or released by the test sample For guidelines on selecting applicable test parameters, see G[3/T2424.13---2002 "Environmental testing for electric and electronic products Part 2: Guidelines for temperature change tests, which should be used together with this part. 1 Test Na: Rapid Temperature Change with Specified Transition Time 1.1 Purpose
The exposure time required to determine the ability of parts, equipment, and other products to withstand rapid changes in ambient temperature depends on the nature of the test specimen.
1.2 General Description of the Test
The test specimen is exposed alternately to low and high temperature air (or a suitable environment (rest) to subject it to rapid temperature changes. 1.3 Description of the Test Equipment
1.3.7 Test Chamber
1.3.1.1 Two test chambers are provided: a low-temperature chamber and a high-temperature chamber. The two chambers are positioned so that the test specimens can be transferred from one chamber to the other within the specified time. The transfer method can be manual or automatic. 1.3.1.2 The air temperature specified in the test shall be maintained in any area of the test chamber where the test specimens are placed. 1.3.1.3 The absolute humidity of the air in the chamber shall not exceed 20 g/m3 of water vapor. 1.3.1.4 The wall temperature of the high-temperature chamber shall not exceed the specified temperature of the test ( 3% of the test temperature (according to the Kelvin thermometer). The wall temperature of the low temperature box should not exceed 8% of the specified test temperature (according to the Kelvin thermometer). This requirement applies to the entire test box, and the test sample should not be subjected to direct radiation from any heating or cooling element that does not meet the above requirements. 1.3.1.5 The volume and air velocity of the test box are such that after the test sample is placed, the time for the air temperature in the box to return to the specified tolerance range shall not exceed 10% of the test exposure time. 1.3.1.6 The air in the box should be circulated. The air flow rate around the test sample should not be less than 2m/s. 1.3.2 Mounting frame and support parts of the test sample Unless otherwise specified in the relevant specifications, the thermal conductivity of the mounting frame and support parts is low, so that the test sample and the mounting frame are actually insulated. 153
GB/T 2423.22—2002/IEC 60068-2-14:1984 hot. When several test samples are tested simultaneously, air can circulate freely between the test samples and between the test samples and the chamber walls. 1.4 Severity Level
1.4.1 The severity level of the test is determined by the low and high temperature values of the test, the switching time and the number of cycles. 1.4.2 The relevant specifications shall specify the low temperature T, which shall be selected from the test temperatures specified in GB/T2423.1-2001 Test A: Low temperature and GB/T2423.2-2001 Test [3; High temperature. The relevant specifications shall specify the high temperature T. This temperature shall be selected from the test temperatures specified in GB3/T2423.1--2001 Test A: Low temperature and GB/T2423.2-2001 Test B: High temperature. 1.4.3 Unless otherwise specified in the relevant Yao standard, the number of cycles shall be 5. 1.4.4 Unless otherwise specified in the relevant specification, the switching time t2 shall be (2~3) min. 1.5 Initial inspection
Carry out visual inspection and electrical and mechanical performance inspection of the test samples according to the requirements of the relevant specifications. 1.6 Conditioning test
1.6.1 The test sample shall be tested in the unpackaged, unpowered, ready-to-use state or other state specified in the relevant specifications. At the beginning of the conditioning test, the temperature of the test sample shall be the test environment temperature. 1.6.2 The length of each exposure test time 1: at low temperature and high temperature depends on the heat capacity of the test sample. According to the relevant specifications, the exposure time shall be 3h, 2h, 1h, 30min or 10min. If the relevant specifications do not specify the test exposure time, it shall be 3h. Note 1: The exposure test time of 10min is applicable to the small test sample. Note 2: Considering the requirements of 1.3.2., attention should be paid to the thermal time constant of the test sample and the technical performance of the existing test chamber. 1.6.3 The temperature in the low temperature chamber is pre-adjusted to the required low temperature T, and then the test sample is placed in the chamber. 1.6.4 The temperature of the low temperature chamber shall be maintained at T: for the specified time t: The t value includes the time when the temperature in the chamber stabilizes to T\ after the test sample is placed. The time required should not be greater than 0.1 (see 1.3.1.5). Jiang: The test exposure time i is calculated from the moment the test sample is placed in the test box. 1.6.5 Conversion time t
The test sample is then transferred from the low temperature box to the high temperature box. The conversion time 2 includes the time to take it out from the first box and the time to put it into the first box, as well as the time to stay at the test environment temperature.
The conversion time should be: (2~3)min, (20~30)s, ≤10 s. Note: The selection of the conversion time depends on the thermal time constant of the test sample and the most rapid temperature change conditions it experiences during use. Note 2: For some harsh conditions, f can be specified as (20~-30). Note 3: For small test samples under harsh conditions, t2 can be specified to be less than 1(h . Allow 4: For shorter switching times: Automatic switching test equipment can be used. 1.6.6 The temperature of the high temperature box should be maintained at high temperature T= for a specified time tt. The value includes the time required for the temperature in the box to stabilize to T after the test sample is placed. This time should not be greater than 0.1 (. (See 1.3.1.5). Note: The exposure time is calculated from the moment the test sample is placed in the box. 1.6.7 The test sample is transferred to the low temperature box according to the switching time specified in 1.6.5. The next cycle is carried out. 1.6.8 The first cycle consists of two exposure times 1 and two switching times (see Figure 1) 1. 6.9 Unless otherwise specified in the relevant specifications, the test sample shall be subjected to 5 cycles according to each procedure of 1.6.3 to 1.t.8. After the test is carried out for the specified time, if the next transition from low temperature to high temperature or from high temperature to low temperature cannot be started immediately (such as overnight or a week's rest, etc.), the test sample shall be kept in the cold box. 1.6.10 At the end of the last cycle, the test sample shall undergo a recovery procedure according to 1.7, 454
Precision/℃
A--—Start of the first cycle:
B—End of the first cycle, start of the second cycle, Note: See 1.3.1.5 for the explanation of the dotted line,
1.7 Recovery
GB/T 2423.22--2002/IEC 60068-2-14: 1984B
1 cycle
1.7.1 After the conditioning test, the test specimen shall be restored under the standard atmospheric conditions of the test for a period of time sufficient to achieve temperature stability. 1.7.2 For specific types of test specimens, the relevant specification may specify a corresponding recovery time. 1.8 Final test
The test specimen shall be visually inspected and its electrical and mechanical properties shall be tested in accordance with the requirements of the relevant specification. 1.9 Information to be given in the relevant specification
When the relevant specification includes this test, the following details shall be given as far as possible: Clause number
Installation and support of test specimens (if otherwise specified)a
Low temperature T. and high temperature T:
Number of cycles (if not 5)
Initial test
State of the test specimen when placed in the test chamber
Exposure time t, (if not 3 h)
If the switching time t2 is not (23) min, then select its value g)
Extension of duration
j) Final test
2 Test Nb: Temperature change at a specified rate of change 2.1 Purpose
To determine the ability of components, equipment and other products to withstand changes in ambient temperature and their ability to operate during changes in ambient temperature. 2.2 General description of the test
The test specimens are exposed to a test chamber that can be changed to a specified temperature at a controlled rate. The performance of the test specimens can be monitored during the exposure period.
GB/T2423.22—2002/1EC 60068-2-14:19842.3 Description of the test equipment
2.3.1 Test chamber
2.3.1.1 The test chamber is designed to ensure that the air in any area where the test specimens are placed can be subjected to temperature cycles as follows. a) Able to maintain the low temperature required by the test:
b) Able to maintain the high temperature required by the test:
c) The change process from low temperature to high temperature or from high temperature to low temperature can be carried out at the temperature change rate required by the test. 2.3.1.2 The absolute concentration of air in the box should not exceed 20/m3 of water vapor. 2.3.1.3 During the temperature stabilization period, the box wall temperature should not differ from the following values of the ambient temperature specified in the test (according to the Kelvin thermometer): not more than 3 at high temperature and not more than 8% at low temperature. This requirement applies to the entire test box rate and the test sample should not be directly radiated by any heating or cooling element that does not meet the above requirements. 2.3.1.4 The air in the test box should be fully circulated. The air velocity around the test sample shall not be less than 211/s. 2.3.2 The mounting frame and support of the test sample shall have low heat conduction unless otherwise specified in the relevant specifications: the test sample and the mounting frame are actually insulated. When several test samples are tested at the same time, the air between each test sample and the test sample and the box wall shall be able to circulate freely. 2.4 Severity level
2.4.1 The severity level of the test is determined by the low and high temperature values of the test. The change rate of the mixing temperature and the number of cycles. 2.4.2 The relevant specifications shall specify the low temperature Ts. T. shall be selected from the test temperatures specified in GB/T2423.1-2001 and GB/T2423.2--2001.
The relevant specifications shall specify the high temperature 7. T shall be selected from the test temperatures specified in GB/T2423.12001 and GB/T2423.2--2001.
2.4.3 Unless otherwise specified in the relevant specifications, the temperature rise and fall rate of the test chamber shall not exceed the average value of 5min. The sample selection shall be (1±0.2)/min. (3±0.6)C/min or (511)C/min. For the description of the relationship between the temperature gradient and the mass and thermal time constant of the test product, see GB/T2124.13-2002.2.4.4 Unless otherwise specified in the relevant specifications, the number of cycles shall be 2. 2.5 Initial test
Perform visual inspection and electrical and mechanical performance tests on the test samples in accordance with the requirements of the agency specifications. 2.6 Condition test
2.6.1 Place the test samples at the test room temperature in the test chamber at the same temperature. The test samples are in a state of unpacking, unpowered and ready for use, or otherwise specified in the relevant specifications. 2.6.2 If required by the relevant specifications, the test samples can be in a running state. 2.6.3 Then the temperature of the test chamber is lowered to the specified low temperature Ts at the specified cooling rate (see 2.4.3). 2.6.4 The exposure time t at each of the two temperatures depends on the heat capacity of the test sample. According to the relevant specifications, t is 3h, 2h, 1h30min or 10min. If the relevant specifications do not specify the exposure time, it is considered to be 3h. 2.6.5 After the temperature of the test chamber reaches stability, the test sample is exposed to the low temperature condition for the specified time of the test. 2.6.6 Then the test temperature is raised to the specified high temperature T2.6 at the specified heating rate (see 2.4.3).7 After the temperature of the test chamber reaches stability, the test sample is exposed to high temperature conditions for the specified time 1. 2.6.8 Then the temperature in the chamber is reduced to the test room ambient temperature value at the specified cooling rate (see 2.4.3). 2.6.9 This procedure constitutes a cycle (see Figure 2) 2.6.10 Unless otherwise specified in the relevant specifications, the test sample should be subjected to a connection cycle. 2.6.11 The relevant specifications should specify:
) The items of electrical and mechanical performance tests to be carried out during the test; b) How many cycles after which these tests are carried out, 2.6.12 Before the test sample is removed from the test chamber, it should be allowed to reach temperature stability at the test air environment temperature. 158
Overflow in the box/℃
…The first cycleπ begins;
The first cycle ends, and the second cycle begins: 2.7 Recovery
The first cycle
GB/T 2423.222002/1EC 60068-2-14:1984The second cycle
2.7.1 End of conditional test: Keep the test sample under the test standard atmospheric conditions to recover for a time sufficient to achieve temperature stability. 2.7.2 For specific types of test samples, the relevant specifications may specify the corresponding recovery time. 2.8 Final test
The test specimens shall be inspected visually and tested for electrical and mechanical properties in accordance with the requirements of the relevant specification. 2.9 Information to be given in the relevant specification
When the relevant specification includes this test, the following details shall be given as far as possible: Clause number
Mounting and support of test specimens (if otherwise specified)a)
Low temperature T and high temperature T:
Rate of temperature change
Number of cycles (if not 2)
Initial test
State of test specimens placed in the test chamber
Exposure time if not h)
Condition test periodElectrical and mechanical properties test, and several cycles of reversal test. i) Recovery
i) Final test
3 Test Ne: Rapid temperature change with two liquid tanks 3.1 Purpose
To determine the ability of components, equipment or other products to withstand rapid temperature changes. 2.3.2
This test procedure produces a rapid thermal shock and is suitable for glass-to-metal seals and similar test specimens. 3.2 General description of the test
The test specimen is alternately placed in two tanks, one tank containing a liquid at a low temperature T and the other containing a liquid at a high temperature T. 3.3 Description of the test apparatus
33.1 Two tanks are provided, a low humidity tank and a high temperature tank. During the test, the test specimen shall be able to be easily inserted and quickly transferred from one tank to another. The liquid shall not be stirred. 437
GB/T2423.22—2002/IFC60068-2-14:19843.3.2 The low temperature tank shall be filled with a liquid at a low temperature T as specified in the relevant specification. If not specified, the liquid temperature shall be 0°C. 3.3.3 The high temperature tank shall be filled with a liquid at a temperature of 7°C as specified in the relevant specification. If not specified, the liquid temperature shall be 100°C. 3.3.4 The structure of the two liquid tanks shall ensure that the temperature rise of the low temperature tank does not exceed 2 of the value of T during the test, and the temperature drop of the high temperature tank shall not be lower than 5°C of T. 3.3.5 The liquid used in the test shall be compatible with the materials and insulation used in the production of the test sample. Note: Within the specified temperature range, the heat exchange rate is faster than the liquid used. The daily heat exchange rate will affect the severity of the test. In special cases, the relevant specifications should specify the liquid to be used. 3. 4 Severity level
3.4.1 The severity level of the test is determined by the specified tank liquid temperature, the switching time from one tank to another and the number of cycles. 3.4.2 This test has two sets of standardized duration parameters: The first set: t = (8 ± 2) s5min ≤ t < 20min (see 3.6.3 ~ 3.6.5) The second set: = (2 ± 1) s15st5min (see 3.6.3 ~ 3.6.5) The relevant specifications should specify the duration parameters to be used and the selected values. 3.4. 3 Unless otherwise specified in the relevant specifications, the number of cycles shall be 10. 3.5 Initial test
Perform visual inspection and electrical and mechanical performance tests on the test samples in accordance with the requirements of the relevant specifications. 3.6 Condition test
3.6.1 The test samples shall be tested without packaging. 3.6.2 During the test, place the test samples in the test room environment into a low-temperature liquid tank at the temperature specified in the relevant specifications. 3.6.3 The test samples are immersed in the low-temperature liquid tank for a certain period of time. 3.6.4 The test samples are taken out of the low-temperature tank. 3.6.5 The test sample is immersed in the high temperature liquid tank for: time. 3.6.6 The test sample is then taken out of the high temperature tank, taken out of the high temperature tank and immersed in the low temperature tank for: time. The transition time: shall be as specified in 3.1.2.
One cycle includes two immersion times t, two transition times + 2 (see Figure 3). 3.6.8 Unless otherwise specified in the relevant specification, the test sample shall be subjected to 10 cycles. 3.6.9 At the end of the last cycle, the test sample shall be subjected to the recovery procedure specified in 3.7. Temperature inside the grapefruit
[cycle
·--The first cycle starts
The first cycle ends and the second cycle begins. Figure 3
3.7 Recovery
GB/T 2423.22—2002/IEC 60068-2-14:19843.7.1 After the condition test, the test sample shall be restored under the standard atmospheric conditions of the test for a time sufficient to achieve temperature stability. Remove droplets from the test sample. If necessary, the relevant specification may specify that the test sample be allowed to be used to remove deposits on the test sample. 3.7.2 For specific types of test samples, the relevant specification may specify corresponding recovery time. 3.8 Final inspection
Inspect the appearance and test the electrical and mechanical properties of the test sample in accordance with the requirements of the relevant specification. 9 Information to be given in the relevant specification
When the relevant specification contains a wood test, the following details should be given as applicable as possible. Clause number
a) Duration: First or second set of parameters and values Number of cycles (if not 10)
Overfill of low temperature tank (if not 0C)
Temperature of high temperature tank (if not 100C)
Liquid used
f) Initial test
Final test
3. 3. 2.3.6.2
3.3.3.3.6.42 General description of the test
The test sample is alternately placed in two liquid tanks, one tank is filled with a low temperature T liquid, and the other is filled with a high temperature T liquid. 3.3 Description of the test equipment
33.1 There are two tanks, a low humidity tank and a high temperature tank. During the test, the test sample should be able to be easily inserted and quickly transferred from one tank to another. The liquid cannot be stirred. 437
GB/T2423.22—2002/IFC60068-2-14:19843.3.2 The low temperature tank should be filled with a low temperature T liquid specified in the relevant specifications. If not specified, the liquid temperature should be 0C. 3.3.3 The high temperature tank should be filled with a commercial temperature 7 liquid specified in the relevant specifications. If not specified, the liquid temperature shall be 100°C. 3.3.4 The structure of the two liquid tanks shall ensure that the temperature rise of the low temperature tank does not exceed 2 of the value of T during the test, and the temperature drop of the high temperature tank shall not be lower than 5°C of T. 3.3.5 The liquid used in the test shall be compatible with the materials and insulation used in the production of the test sample. Note: Within the specified temperature range, the heat exchange rate is faster than the liquid used. The daily heat exchange rate will affect the severity of the test. In special cases, the relevant specifications should specify the liquid to be used. 3. 4 Severity level
3.4.1 The severity level of the test is determined by the specified tank liquid temperature, the switching time from one tank to another and the number of cycles. 3.4.2 This test has two sets of standardized duration parameters: The first set: t = (8 ± 2) s5min ≤ t < 20min (see 3.6.3 ~ 3.6.5) The second set: = (2 ± 1) s15st5min (see 3.6.3 ~ 3.6.5) The relevant specifications should specify the duration parameters to be used and the selected values. 3.4. 3 Unless otherwise specified in the relevant specifications, the number of cycles shall be 10. 3.5 Initial test
Perform visual inspection and electrical and mechanical performance tests on the test samples in accordance with the requirements of the relevant specifications. 3.6 Condition test
3.6.1 The test samples shall be tested without packaging. 3.6.2 During the test, place the test samples in the test room environment into a low-temperature liquid tank at the temperature specified in the relevant specifications. 3.6.3 The test samples are immersed in the low-temperature liquid tank for a certain period of time. 3.6.4 The test samples are taken out of the low-temperature tank. 3.6.5 The test sample is immersed in the high temperature liquid tank for: time. 3.6.6 The test sample is then taken out of the high temperature tank, taken out of the high temperature tank and immersed in the low temperature tank for: time. The transition time: shall be as specified in 3.1.2.
One cycle includes two immersion times t, two transition times + 2 (see Figure 3). 3.6.8 Unless otherwise specified in the relevant specification, the test sample shall be subjected to 10 cycles. 3.6.9 At the end of the last cycle, the test sample shall be subjected to the recovery procedure specified in 3.7. Temperature inside the grapefruit
[cycle
·--The first cycle starts
The first cycle ends and the second cycle begins. Figure 3
3.7 Recovery
GB/T 2423.22—2002/IEC 60068-2-14:19843.7.1 After the condition test, the test sample shall be restored under the standard atmospheric conditions of the test for a time sufficient to achieve temperature stability. Remove droplets from the test sample. If necessary, the relevant specification may specify that the test sample be allowed to be used to remove deposits on the test sample. 3.7.2 For specific types of test samples, the relevant specification may specify corresponding recovery time. 3.8 Final inspection
Inspect the appearance and test the electrical and mechanical properties of the test sample in accordance with the requirements of the relevant specification. 9 Information to be given in the relevant specification
When the relevant specification contains a wood test, the following details should be given as applicable as possible. Clause number
a) Duration: First or second set of parameters and values Number of cycles (if not 10)
Overfill of low temperature tank (if not 0C)
Temperature of high temperature tank (if not 100C)
Liquid used
f) Initial test
Final test
3. 3. 2.3.6.2
3.3.3.3.6.42 General description of the test
The test sample is alternately placed in two liquid tanks, one tank is filled with a low temperature T liquid, and the other is filled with a high temperature T liquid. 3.3 Description of the test equipment
33.1 There are two tanks, a low humidity tank and a high temperature tank. During the test, the test sample should be able to be easily inserted and quickly transferred from one tank to another. The liquid cannot be stirred. 437
GB/T2423.22—2002/IFC60068-2-14:19843.3.2 The low temperature tank should be filled with a low temperature T liquid specified in the relevant specifications. If not specified, the liquid temperature should be 0C. 3.3.3 The high temperature tank should be filled with a commercial temperature 7 liquid specified in the relevant specifications. If not specified, the liquid temperature shall be 100°C. 3.3.4 The structure of the two liquid tanks shall ensure that the temperature rise of the low temperature tank does not exceed 2 of the value of T during the test, and the temperature drop of the high temperature tank shall not be lower than 5°C of T. 3.3.5 The liquid used in the test shall be compatible with the materials and insulation used in the production of the test sample. Note: Within the specified temperature range, the heat exchange rate is faster than the liquid used. The daily heat exchange rate will affect the severity of the test. In special cases, the relevant specifications should specify the liquid to be used. 3. 4 Severity level
3.4.1 The severity level of the test is determined by the specified tank liquid temperature, the switching time from one tank to another and the number of cycles. 3.4.2 This test has two sets of standardized duration parameters: The first set: t = (8 ± 2) s5min ≤ t < 20min (see 3.6.3 ~ 3.6.5) The second set: = (2 ± 1) s15st5min (see 3.6.3 ~ 3.6.5) The relevant specifications should specify the duration parameters to be used and the selected values. 3.4. 3 Unless otherwise specified in the relevant specifications, the number of cycles shall be 10. 3.5 Initial test
Perform visual inspection and electrical and mechanical performance tests on the test samples in accordance with the requirements of the relevant specifications. 3.6 Condition test
3.6.1 The test samples shall be tested without packaging. 3.6.2 During the test, place the test samples in the test room environment into a low-temperature liquid tank at the temperature specified in the relevant specifications. 3.6.3 The test samples are immersed in the low-temperature liquid tank for a certain period of time. 3.6.4 The test samples are taken out of the low-temperature tank. 3.6.5 The test sample is immersed in the high temperature liquid tank for: time. 3.6.6 The test sample is then taken out of the high temperature tank, taken out of the high temperature tank and immersed in the low temperature tank for: time. The transition time: shall be as specified in 3.1.2.
One cycle includes two immersion times t, two transition times + 2 (see Figure 3). 3.6.8 Unless otherwise specified in the relevant specification, the test sample shall be subjected to 10 cycles. 3.6.9 At the end of the last cycle, the test sample shall be subjected to the recovery procedure specified in 3.7. Temperature inside the grapefruit
[cycle
·--The first cycle starts
The first cycle ends and the second cycle begins. Figure 3
3.7 Recovery
GB/T 2423.22—2002/IEC 60068-2-14:19843.7.1 After the condition test, the test sample shall be restored under the standard atmospheric conditions of the test for a time sufficient to achieve temperature stability. Remove droplets from the test sample. If necessary, the relevant specification may specify that the test sample be allowed to be used to remove deposits on the test sample. 3.7.2 For specific types of test samples, the relevant specification may specify corresponding recovery time. 3.8 Final inspection
Inspect the appearance and test the electrical and mechanical properties of the test sample in accordance with the requirements of the relevant specification. 9 Information to be given in the relevant specification
When the relevant specification contains a wood test, the following details should be given as applicable as possible. Clause number
a) Duration: First or second set of parameters and values Number of cycles (if not 10)bzxZ.net
Overfill of low temperature tank (if not 0C)
Temperature of high temperature tank (if not 100C)
Liquid used
f) Initial test
Final test
3. 3. 2.3.6.2
3.3.3.3.6.4
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.