The walk-in high and low temperature (humid and hot) laboratory also needs maintenance

The walk-in high and low temperature (humid and hot) laboratory also needs maintenance

Reminder: Remember to maintain the walk-in high and low temperature (humid and hot) laboratory as well!

1. The temperature and humidity testing system of the walk-in high and low temperature (humid and hot) laboratory must be operated and maintained by a dedicated person. Strictly follow the operating procedures of the system and avoid others from operating the system illegally.

2. Long term shutdown of the walk-in high and low temperature (humid and hot) laboratory can affect the effective service life of the system. Therefore, the system should be turned on and operated at least once every 10 days; Do not repeatedly stop the system in a short period of time. The number of starts per hour should be less than 5 times, and the time interval between each start stop should not be less than 3 times; Do not open the door of the walk-in temperature and humidity testing system at low temperatures to prevent damage to the door sealing tape.

3. A system usage file should be established to facilitate system maintenance and repair. The use of archives should record the start and end time (date) of each system operation, the type of experiment, and the ambient temperature; When the system malfunctions, provide a detailed description of the fault phenomenon as much as possible; The maintenance and repair of the system should also be recorded in as much detail as possible.

4. Conduct a monthly main power switch (leakage circuit breaker) operation test to ensure that the switch is used as a leakage protector while meeting the load capacity. The specific steps are as follows: first, please confirm that the main power switch is turned to "ON", which means the system is powered on, and then press the test button. If the switch lever of the residual current circuit breaker falls down, this function is normal.

5. The main box of the walk-in temperature and humidity testing system should be protected during use and should not be subjected to strong impacts from sharp or blunt objects.

6. To ensure the normal and clean supply of cooling water, the cooling water filter of the refrigeration unit should be cleaned every 30 days. If the local air quality is poor and the dust content in the air is high, the cooling water tower reservoir should generally be cleaned every 7 days.

7. The leakage, overload, and short-circuit protection characteristics of the residual current switch are set by Lab Companion manufacturer and cannot be adjusted arbitrarily during use to avoid affecting performance; After the leakage switch is disconnected due to a short circuit, the contacts need to be checked. If the main contacts are severely burned or have pits, maintenance is required.

8. The test products placed in the walk-in temperature and humidity testing system should be kept at a certain distance from the suction and exhaust ports of the air conditioning channel to avoid obstructing air circulation.

9. Overtemperature protector action test. Set the temperature of the over temperature protector to be lower than the temperature of the box. If there is an E0.0 alarm and buzzing sound, it indicates that its function is normal. After completing the above experiment, the temperature protection setting should be reset appropriately, otherwise it may cause inappropriate termination.

10. Once a year, use a vacuum cleaner to clean and remove dust from the distribution room and water circuit room. Once a month, use a dry cloth to clean the accumulated water in the water tray of the refrigeration unit.

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User selection environment test box must read

User selection environment test box must read

1、 Equipment selection criteria

There is currently no exact number of natural environmental factors and induced environmental factors that exist on the surface of the Earth and in the atmosphere, among which there are no less than a dozen factors that have a significant impact on the use and lifespan of engineering products (equipment). Engineers engaged in the study of environmental conditions for engineering products have compiled and summarized the environmental conditions that exist in nature and are induced by human activities into a series of testing standards and specifications to guide the environmental and reliability testing of engineering products. For example, GJB150- the National Military Standard of the People's Republic of China for Environmental Testing of Military Equipment, and GB2423- the National Standard of the People's Republic of China for Environmental Testing of Electrical and Electronic Products, which guides environmental testing of electrical and electronic products. Therefore, the main basis for selecting environmental and reliability testing equipment is the testing specifications and standards of engineering products.

Secondly, in order to standardize the tolerance of environmental testing conditions in experimental equipment and ensure the control accuracy of environmental parameters, national technical supervision agencies and various industrial departments have also formulated a series of calibration regulations for environmental testing equipment and detection instruments. Such as the national standard GB5170 of the People's Republic of China "Basic Parameter Calibration Method for Environmental Testing Equipment of Electrical and Electronic Products", and JJG190-89 "Trial Calibration Regulations for Electric Vibration Test Stand System" issued and implemented by the State Administration of Technical Supervision. These verification regulations are also an important basis for selecting environmental and reliability testing equipment. Testing equipment that does not meet the requirements of these verification regulations is not allowed to be put into use.

2、 Basic principles for equipment selection

The selection of environmental and reliability testing equipment should follow the following five basic principles:

1. Reproducibility of environmental conditions

It is impossible to fully and accurately reproduce the environmental conditions that exist in nature in the laboratory. However, within a certain tolerance range, people can accurately and approximately simulate the external environmental conditions that engineering products undergo during use, storage, transportation, and other processes. This passage can be summarized in engineering language as follows: "The environmental conditions (including platform environment) created by the testing equipment around the tested product should meet the requirements of the environmental conditions and their tolerances specified in the product testing specifications. The temperature box used for military product testing should not only meet the requirements of the national military standards GJB150.3-86 and GJB150.4-86 for different uniformity and temperature control accuracy. Only in this way can the reproducibility of environmental conditions be ensured in environmental testing.

2. Repeatability of environmental conditions

An environmental testing equipment may be used for multiple tests of the same type of product, and a tested engineering product may also be tested in different environmental testing equipment. In order to ensure the comparability of test results obtained for the same product under the same environmental testing conditions specified in the testing specifications, it is necessary to require the environmental conditions provided by the environmental testing equipment to be reproducible. This means that the stress levels (such as thermal stress, vibration stress, electrical stress, etc.) applied by environmental testing equipment to the tested product are consistent with the requirements of the same testing specification.

The repeatability of environmental conditions provided by environmental testing equipment is guaranteed by the national metrological verification department after passing the verification according to the verification regulations formulated by the national technical supervision agency. Therefore, it is necessary to require environmental testing equipment to meet the requirements of various technical indicators and accuracy indicators in the calibration regulations, and to not exceed the time limit specified in the calibration cycle in terms of usage time. If a very common electric vibration table is used, in addition to meeting technical indicators such as excitation force, frequency range, and load capacity, it must also meet the requirements of precision indicators such as lateral vibration ratio, table acceleration uniformity, and harmonic distortion specified in the calibration regulations. Moreover, the service life after each calibration is two years, and after two years, it must be re calibrated and qualified before being put into use.

3. Measurability of environmental condition parameters

The environmental conditions provided by any environmental testing equipment must be observable and controllable. This is not only to limit the environmental parameters within a certain tolerance range and ensure the reproducibility and repeatability of the test conditions, but also necessary for the safety of product testing, in order to prevent damage to the tested product caused by uncontrolled environmental conditions and unnecessary losses. At present, various experimental standards generally require that the accuracy of parameter testing should not be less than one-third of the allowable error under experimental conditions.

4. Exclusion of environmental testing conditions

Every time an environmental or reliability test is conducted, there are strict regulations on the category, magnitude, and tolerance of environmental factors, and non test required environmental factors are excluded from penetrating into it, in order to provide a definite basis for judging and analyzing product failure and fault modes during or after the test. Therefore, it is required that environmental testing equipment not only provide the specified environmental conditions, but also not allow any other environmental stress interference to be added to the tested product. As defined in the verification regulations for electric vibration tables, the table leakage magnetic flux, acceleration signal-to-noise ratio, and total root mean square value ratio of in band and out of band acceleration. The accuracy indicators such as random signal verification and harmonic distortion are all established as verification items to ensure the uniqueness of environmental testing conditions.

5. Safety and reliability of experimental equipment

Environmental testing, especially reliability testing, has a long testing cycle and sometimes targets high-value military products. During the testing process, testing personnel often need to operate, inspect or test around the site. Therefore, it is required that environmental testing equipment must have the characteristics of safe operation, convenient operation, reliable use, and long working life to ensure the normal progress of the testing itself. The various protection, alarm measures, and safety interlock devices of the testing equipment should be complete and reliable to ensure the safety and reliability of the testing personnel, the tested products, and the testing equipment itself.

3、 Selection of Temperature and Humidity Chamber

1. Selection of Capacity

When placing the test product (components, assemblies, parts or whole machine) into a climate chamber for testing, in order to ensure that the atmosphere around the test product can meet the environmental testing conditions specified in the test specifications, the working dimensions of the climate chamber and the overall dimensions of the test product should follow the following regulations:

a) The volume of the tested product (W × D × H) shall not exceed (20-35)% of the effective working space of the test chamber (20% is recommended). For products that generate heat during testing, it is recommended to use no more than 10%.

b) The ratio of the windward cross-sectional area of the tested product to the total area of the test chamber on that section shall not exceed (35-50)% (35% is recommended).

c) The distance between the outer surface of the tested product and the wall of the test chamber should be kept at least 100-150mm (recommended 150mm).

The above three provisions are actually interdependent and unified. Taking a 1 cubic meter cube box as an example, an area ratio of 1: (0.35-0.5) is equivalent to a volume ratio of 1: (0.207-0.354). A distance of 100-150mm from the box wall is equivalent to a volume ratio of 1: (0.343-0.512).

In summary, the working chamber volume of the climate environment test chamber should be at least 3-5 times the external volume of the tested product. The reasons for making such regulations are as follows:

After the test piece is placed in the box, it occupies the smooth channel, and narrowing the channel will lead to an increase in airflow velocity. Accelerate the heat exchange between the airflow and the test piece. This is inconsistent with the reproduction of environmental conditions, as relevant standards stipulate that the air flow velocity around the test specimen in the test chamber should not exceed 1.7m/s for temperature environmental tests, in order to prevent the test specimen and the surrounding atmosphere from generating heat conduction that is not in line with reality. When unloaded, the average wind speed inside the test chamber is 0.6-0.8m/s, not exceeding 1m/s. When the space and area ratio specified in points a) and b) are met, the wind speed in the flow field may increase by (50-100)%, with an average maximum wind speed of (1-1.7) m/s. Meet the requirements specified in the standards. If the volume or windward cross-sectional area of the test piece is increased without restrictions during the experiment, the actual airflow speed during the test will exceed the maximum wind speed specified in the test standard, and the validity of the test results will be questioned.

The accuracy indicators of environmental parameters in the working chamber of the climate chamber, such as temperature, humidity, salt spray settling rate, etc., are all measured under no-load conditions. Once the test piece is placed, it will have an impact on the uniformity of the environmental parameters in the working chamber of the test chamber. The larger the space occupied by the test piece, the more severe this impact will be. Experimental data shows that the temperature difference between the windward and leeward sides in the flow field can reach 3-8 ℃, and in severe cases, it can be as high as 10 ℃ or more. Therefore, it is necessary to meet the requirements of a] and b] as much as possible to ensure the uniformity of environmental parameters around the tested product.

According to the principle of heat conduction, the temperature of the airflow near the box wall is usually 2-3 ℃ different from the temperature at the center of the flow field, and may even reach 5 ℃ at the upper and lower limits of high and low temperatures. The temperature of the box wall differs from the temperature of the flow field near the box wall by 2-3 ℃ (depending on the structure and material of the box wall). The greater the difference between the test temperature and the external atmospheric environment, the greater the temperature difference. Therefore, the space within a distance of 100-150mm from the box wall is unusable.

2. Selection of temperature range

At present, the range of temperature test chambers abroad is generally -73 to+177 ℃, or -70 to+180 ℃. Most domestic manufacturers generally operate at -80 to+130 ℃, -60 to+130 ℃, -40 to+130 ℃, and there are also high temperatures up to 150 ℃. These temperature ranges can usually meet the temperature testing needs of the vast majority of military and civilian products in China. Unless there are special requirements, such as products installed near heat sources such as engines, the upper temperature limit should not be blindly increased. Because the higher the upper limit temperature, the greater the temperature difference between the inside and outside of the box, and the poorer the uniformity of the flow field inside the box. The smaller the available studio size. On the other hand, the higher the upper limit temperature value, the higher the heat resistance requirements for insulation materials (such as glass wool) in the interlayer of the box wall. The higher the requirement for the sealing of the box, the higher the production cost of the box.

3. Selection of humidity range

The humidity indicators given by domestic and foreign environmental test chambers are mostly 20-98% RH or 30-98% RH. If the humid heat test chamber does not have a dehumidification system, the humidity range is 60-98%. This type of test chamber can only perform high humidity tests, but its price is much lower. It is worth noting that the corresponding temperature range or minimum dew point temperature should be indicated after the humidity index. Because relative humidity is directly related to temperature, for the same absolute humidity, the higher the temperature, the lower the relative humidity. For example, if the absolute humidity is 5g/Kg (referring to 5g of water vapor in 1kg of dry air), when the temperature is 29 ℃, the relative humidity is 20% RH, and when the temperature is 6 ℃, the relative humidity is 90% RH. When the temperature drops below 4 ℃ and the relative humidity exceeds 100%, condensation will occur inside the box.

To achieve high temperature and high humidity, simply spray steam or atomized water droplets into the air of the box for humidification. Low temperature and humidity are relatively difficult to control because the absolute humidity at this time is very low, sometimes much lower than the absolute humidity in the atmosphere. It is necessary to dehumidify the air flowing inside the box to make it dry. At present, the vast majority of temperature and humidity chambers both domestically and internationally adopt the principle of refrigeration and dehumidification, which involves adding a set of refrigeration light pipes to the air conditioning room of the chamber. When humid air passes through a cold pipe, its relative humidity will reach 100% RH, as the air saturates and condenses on the light pipe, making the air drier. This dehumidification method theoretically can reach dew point temperatures below zero degrees, but when the surface temperature of the cold spot reaches 0 ℃, the water droplets condensed on the surface of the light pipe will freeze, affecting the heat exchange on the surface of the light pipe and reducing the dehumidification capacity. Also, because the box cannot be completely sealed, humid air from the atmosphere will seep into the box, causing the dew point temperature to rise. On the other hand, the moist air flowing between the light tubes only reaches saturation at the moment of contact with the light tubes (cold spots) and releases water vapor, so this dehumidification method is difficult to keep the dew point temperature inside the box below 0 ℃. The actual minimum dew point temperature achieved is 5-7 ℃. A dew point temperature of 5 ℃ is equivalent to an absolute moisture content of 0.0055g/Kg, corresponding to a relative humidity of 20% RH at a temperature of 30 ℃. If a temperature of 20 ℃ and a relative humidity of 20% RH are required, with a dew point temperature of -3 ℃, it is difficult to use refrigeration for dehumidification, and an air drying system must be selected to achieve it.

4. Selection of control mode

There are two types of temperature and humidity test chambers: constant test chamber and alternating test chamber.

The ordinary high and low temperature test chamber generally refers to a constant high and low temperature test chamber, which is controlled by setting a target temperature and has the ability to automatically maintain a constant temperature to the target temperature point. The control method of the constant temperature and humidity test chamber is also similar, setting a target temperature and humidity point, and the test chamber has the ability to automatically maintain a constant temperature to the target temperature and humidity point. The high and low temperature alternating test chamber has one or more programs for setting high and low temperature changes and cycles. The test chamber has the ability to complete the test process according to the preset curve, and can accurately control the heating and cooling rates within the maximum heating and cooling rate capability range, that is, the heating and cooling rates can be controlled according to the slope of the set curve. Similarly, the high and low temperature alternating humidity test chamber also has preset temperature and humidity curves, and the ability to control them according to the preset. Of course, alternating test chambers have the function of constant test chambers, but the manufacturing cost of alternating test chambers is relatively high because they need to be equipped with curve automatic recording devices, program controllers, and solve problems such as turning on the refrigeration machine when the temperature in the working room is high. Therefore, the price of alternating test chambers is generally more than 20% higher than that of constant test chambers. Therefore, we should take the need for experimental methods as the starting point and choose a constant test chamber or an alternating test chamber.

5. Selection of variable temperature rate

Ordinary high and low temperature test chambers do not have a cooling rate indicator, and the time from the ambient temperature to the nominal lowest temperature is generally 90-120 minutes. The high and low temperature alternating test chamber, as well as the high and low temperature alternating wet heat test chamber, both have temperature change speed requirements. The temperature change speed is generally required to be 1 ℃/min, and the speed can be adjusted within this speed range. The rapid temperature change test chamber has a fast temperature change rate, with heating and cooling rates ranging from 3 ℃/min to 15 ℃/min. In certain temperature ranges, the heating and cooling rates can even reach over 30 ℃/min.

The temperature range of various specifications and speeds of rapid temperature change test chambers is generally the same, that is, -60 to+130 ℃. However, the temperature range for assessing the cooling rate is not the same. According to different test requirements, the temperature range of rapid temperature change test chambers is -55 to+80 ℃, while others are -40 to+80 ℃.

There are two methods for determining the temperature change rate of the rapid temperature change test chamber: one is the average temperature rise and fall rate throughout the entire process, and the other is the linear temperature rise and fall rate (actually the average speed every 5 minutes). The average speed throughout the entire process refers to the ratio of the difference between the highest and lowest temperatures within the temperature range of the test chamber to the time. At present, the technical parameters of temperature change rate provided by various environmental testing equipment manufacturers abroad refer to the average rate throughout the entire process. The linear temperature rise and fall rate refers to the guaranteed temperature change rate within any 5-minute time period. In fact, for the rapid temperature change test chamber, the most difficult and critical stage to ensure the linear temperature rise and fall speed is the cooling rate that the test chamber can achieve during the last 5 minutes of the cooling period. From a certain perspective, the linear heating and cooling speed (average speed every 5 minutes) is more scientific. Therefore, it is best for the experimental equipment to have two parameters: the average temperature rise and fall speed throughout the entire process and the linear temperature rise and fall speed (average speed every 5 minutes). Generally speaking, the linear heating and cooling speed (average speed every 5 minutes) is half of the average heating and cooling speed throughout the entire process.

6. Wind speed

According to relevant standards, the wind speed inside the temperature and humidity chamber during environmental testing should be less than 1.7m/s. For the test itself, the lower the wind speed, the better. If the wind speed is too high, it will accelerate the heat exchange between the surface of the test piece and the airflow inside the chamber, which is not conducive to the authenticity of the test. But in order to ensure uniformity within the testing chamber, it is necessary to have circulating air inside the testing chamber. However, for rapid temperature change test chambers and comprehensive environmental test chambers with multiple factors such as temperature, humidity, and vibration, in order to pursue the rate of temperature change, it is necessary to accelerate the flow velocity of the circulating airflow inside the chamber, usually at a speed of 2-3m/s. Therefore, the wind speed limit varies for different usage purposes.

7. Temperature fluctuation

Temperature fluctuation is a relatively easy parameter to implement, and most test chambers produced by environmental testing equipment manufacturers can actually control temperature fluctuations within a range of ± 0.3 ℃.

8. Uniformity of temperature field

In order to simulate the actual environmental conditions that products experience in nature more accurately, it is necessary to ensure that the surrounding area of the tested product is under the same temperature environment conditions during environmental testing. Therefore, it is necessary to limit the temperature gradient and temperature fluctuation inside the test chamber. In the General Principles of Environmental Test Methods for Military Equipment (GJB150.1-86) of the National Military Standard, it is clearly stipulated that "the temperature of the measurement system near the test sample should be within ± 2 ℃ of the test temperature, and its temperature should not exceed 1 ℃/m or the total maximum value should be 2.2 ℃ (when the test sample is not working).

9. Precision control of humidity

The humidity measurement in the environmental testing chamber mostly adopts the dry wet bulb method. The manufacturing standard GB10586 for environmental testing equipment requires that the relative humidity deviation should be within ± 23% RH. To meet the requirements of humidity control accuracy, the temperature control accuracy of the humidity test chamber is relatively high, and the temperature fluctuation is generally less than ± 0.2 ℃. Otherwise, it will be difficult to meet the requirements for humidity control accuracy.

10. Cooling method selection

If the test chamber is equipped with a refrigeration system, the refrigeration system needs to be cooled. There are two forms of test chambers: air-cooled and water-cooled.

 

Forced air cooling 

   Water-cooling

Working conditions

The equipment is easy to install, only need to power on.

The ambient temperature should be lower than 28℃. If the ambient temperature is higher than 28℃, it has a certain impact on the refrigeration effect (preferably with air conditioning), the circulating cooling water system should be configured.

Heat exchange effect

 Poor (relative to the water-cooling mode)

 Stable, good

 Noise

Large (relative to the water-cooling mode)

   Less

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VHF100(6000LPH) Hydraulic Oil Filtration Machine Sales to Mid East Country

We design, produce and sales two sets of VHF100(6000 liters per hour) Hydraulic Oil Filtration Machine to Mid East country. The Hydraulic Oil Filter Machine is important for the hydraulic system with its precise filtration technology and high filtration efficiency. It adopts advanced filter materials, such as steel screen, polymer fiber filter element, etc., which can efficiently intercept and remove particles, moisture, the vacuum dehydration and degassing system can remove water, gases and harmful substances to ensure the purity and stability of the hydraulic oil. Hydraulic Oil Filtration Machine not only reduces wear and corrosion inside the hydraulic system, but also significantly improves the operating efficiency and stability of the system.

 

VHF Hydraulic Oil Filter Machine can greatly extend the service life of hydraulic system. In the hydraulic system, the presence of impurities and contaminants will accelerate the aging of the oil and the wear and tear of the equipment, resulting in the degradation of equipment performance and frequent failures. By regularly using a hydraulic oil filter machine, the contaminant content in the oil can be effectively reduced, and the cleanliness and performance of the oil can be kept stable, thereby slowing down the wear rate of the equipment and prolonging the service life of the equipment.

 

The Hydraulic Oil Filtration Machine also has the advantages of easy operation and easy maintenance. It adopts automatic control systems, which realize the functions of one-button operation and automatic cleaning, which greatly reduces the labor intensity and maintenance costs of operators. VHF Hydraulic Oil Filtration Machine can ensure the stable operation of the hydraulic system and prolonging the service life with its precise filtration technology, excellent filtration effect and convenient operation and maintenance characteristics.

Hydraulic Oil Filtration Machine

Hydraulic Oil Filtration Machine

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GRT-50 SF6 Gas Treatment Machine Sales to Spain

Acore Filtration Co.,Ltd manufacture 2 sets of GRT-50 SF6 Gas Treatment Machine to Spain, Europe, which has function of recovery, purification, filling, vacuum evacuation and storage. GRT-50 gas treatment machine is mainly used for GIS electric equipment.

 

GRT SF6 Gas Recovery System adopts mobile type with new technology, new design, full function, reasonable structure, simple and easy operation. The main functions as following:

1. Measurement of vacuum pumping and vacuum degree of the device and electrical equipment.

2. Recover the gas in the electrical equipment.

3. Dry and purify the recovered and recharged SF6 gas.

4. Inflatable SF6 electrical appliances.

5. Compress and store SF6 gas in electrical appliances.

 

Features:

1. The design is high-tech, the function is complete, the structure is reasonable, and the operation is concise and clear.

2. Compression system: SF6 air compressor, no leakage.

3. The vacuum system adopts a two-stage rotary vane vacuum pump, and there is an automatic anti-oil return device in the system.

4. The purification system adopts the principle filter of CKD company in Japan, and the filter adopts electric heating and built-in high-efficiency adsorbent, and the purification effect is more significant (no need to replace the adsorbent frequently).

5. Automatic confirmation of three-phase power supply in the electrical system of the device, automatic protection of phase failure.

6. The device control system adopts the SF6 special valve with the latest technology

7. The storage system is equipped with liquid storage tank according to user requirements.

8. The equipment adopts mobile type.

SF6 Gas Treatment Machine

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Drug Stability Test

Drug Stability Test

The effectiveness and safety of drugs have attracted much attention, and it is also a livelihood issue that the country and the government attach great importance to. The stability of drugs will affect the efficacy and safety. In order to ensure the quality of drugs and storage containers, stability tests should be performed to determine their effective time and storage state. Stability test mainly studies whether the quality of drugs is affected by environmental factors such as temperature, humidity and light, and whether it changes with time and the correlation between them, and studies the degradation curve of drugs, according to which the effective period is presumed to ensure the effectiveness and safety of drugs when used. This article collects the standard information and test methods required for various stability tests for customers' reference.

First, drug stability test criteria

Storage conditions of drugs:

 

Storage conditions (Note 2)

Long-term experiment

25℃±2℃ / 60%±5%RH or

30℃±2℃ /65%±5% RH

Accelerated test

40℃±2℃ / 75%±5%RH

Middle test (Note 1)

30℃±2℃ / 65%±5%RH

Note 1: If the long-term test condition has been set at 30℃±2℃/65% ±5%RH, there is no middle test; if the long-term storage condition is 25℃±2℃/ 60% ±5%RH, and there is a significant change in the accelerated test, then middle test should be added. And should be assessed against the criteria of "significant change".

Note 2: Sealed impervious containers such as glass ampoules can be exempted from humidity conditions. Unless otherwise determined, all tests shall be carried out in accordance with the stability test plan in the interim test.

The accelerated test data should be available for six months. The minimum duration of the stability test is 12 months for the middle test and the long-term test.

 

Store in refrigerator:

 

Storage conditions

Long-term experiment

5℃±3℃

Accelerated test

25℃±2℃ / 60%±5%RH

 

Stored in freezer:

 

Storage conditions

Long-term experiment

-20℃±5℃

Accelerated test

5℃±3℃

If the product containing water or solvents that may be subject to solvent loss is packaged in a semi-permeable container, the stability assessment should be conducted under low relative humidity for a long period of time, or an middle test of 12 months, and an accelerated test of 6 months, in order to prove that the drug placed in the semi-permeable container can withstand the low relative humidity environment.

 

Containing water or solvents

 

Storage conditions

Long-term experiment

25℃±2℃ / 40%±5%RH or 30℃±2℃ /35%±5% RH

Accelerated test

40℃±2℃;≤25%RH

Middle test (Note 1)

30℃±2℃ / 35%RH±5%RH

Note 1: If the long-term test condition is 30℃±2℃ / 35%±5%RH, there is no middle test.

 

The calculation of the relative water loss rate at a constant temperature of 40℃ is as follows:

Substituted relative humidity (A)

Control relative humidity (R)

Water loss rate ratio ([1-R]/[1-A])

60%RH

25%RH

1.9

60%RH

40%RH

1.5

65%RH

35%RH

1.9

75%RH

25%RH

3.0

Illustration: For aqueous drugs placed in semi-permeable containers, the water loss rate at 25%RH is three times that of 75%RH.

 

Second, Drug stability solutions

Common drug stability test criteria

(Source: Food and Drug Administration, Ministry of Health and Welfare)

Item

Storage conditions

Long-term experiment

25°C /60% RH

Accelerated test

40°C /75%RH

Middle test

30°C/65%RH

 

(1) Wide temperature range test

Item

Storage conditions

Long-term experiment

Low or sub-zero temperature conditions

Accelerated test

Room temperature and humidity or low temperature conditions

 

(2) Test equipment

1. Constant temperature and humidity test chamber

2. Drug stability test chamber

constant temperature & humidity test chamber

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Electric Vehicle Component Reliability Test Solution

Electric Vehicle Component Reliability Test Solution

In the trend of global warming and gradual consumption of resources, automotive gasoline is also sharply reduced, electric vehicles are driven by electric energy, reducing the heat of internal combustion engine, carbon dioxide and exhaust gas emissions, for energy saving and carbon reduction and improve the greenhouse effect plays a huge role, electric vehicles are the future trend of road transportation; In recent years, the world's advanced countries actively develop electric vehicles, for thousands of components composed of complex products, its reliability is particularly important, a variety of harsh environments are testing the electronic system of electric vehicles [battery cell, battery system, battery module, electric vehicle motor, electric vehicle controller, battery module and charger...], Hongzhan Technology for you to sort out electric vehicle related parts reliability test solutions, hope to be able to provide customers with reference.

First, different environmental conditions will have different effects on parts and cause them to fail, so the parts of the car need to be tested according to the relevant specifications to meet international requirements and meet the foreign market, the following is the correlation between different environmental conditions and product failure:

A. High temperature will make the product aging, gasification, cracking, softening, melting, expansion and evaporation, resulting in poor insulation, mechanical failure, mechanical stress increase; Low temperature will make the product embrittlement, icing, shrinkage and solidification, mechanical strength reduction, resulting in poor insulation, cracking mechanical failure, sealing failure;

B. High relative humidity will make the product poor insulation, cracking mechanical failure, sealing failure and resulting in poor insulation; Low relative humidity will dehydrate, embrittlement, reduce mechanical strength and lead to cracking and mechanical failure;

C. Low air pressure will cause product expansion, electrical insulation deterioration of the air to produce corona and ozone, low cooling effect and lead to mechanical failure, sealing failure, overheating;

D. Corrosive air will cause product corrosion, electrolysis, surface degradation, increased conductivity, increased contact resistance, resulting in increased wear electrical failure, mechanical failure;

E. Rapid temperature changes will cause local overheating of the product, resulting in cracking deformation and mechanical failure;

F. Accelerated vibration damage or impact will cause the mechanical stress fatigue resonance of the product and lead to an increase in structural damage.

Therefore, products need to pass the following climatic tests to test the reliability of components: Dust (dust) test, high temperature test, temperature and humidity storage test, salt/dry/warm recovery test, temperature and humidity cycle test, immersion/seepage test, salt spray test, low temperature test, thermal shock test, hot air aging test, weather and light resistance test, gas corrosion test, fire resistance test, mud and water test, dew condensation test, high variable temperature cycle test, Rain (waterproof) test, etc.

The following are the test conditions for automotive electronics:

A. IC and interior lights for locomotives,

Recommended model: vibration of the comprehensive chamber

vibration of the comprehensive chamber

B. Instrument panel, motor controller, Bluetooth headset, tire pressure sensor, GPS satellite positioning system, instrument backlight, interior light, exterior light, automotive lithium battery, pressure sensor, motor and controller, automotive DVR, cable, synthetic resin

Recommended model: constant temperature and humidity test chamber

constant temperature and humidity test chamber

C. 8.4 "LCD screen for cars

Recommended model: thermal stress recombination machine

Second, automotive electronic parts are divided into three categories, including IC, discrete semiconductor, passive components three categories, in order to ensure that these automotive electronic components meet the highest standards of automotive safety. The Automotive Electronics Council(AEC) is a set of standards AEC-Q100 designed for active parts (microcontrollers and integrated circuits...)and AEC-Q200 designed for passive components, which specifies the product quality and reliability that must be achieved for passive parts. AEC-Q100 is the vehicle reliability test standard formulated by the AEC organization, which is an important entry for 3C and IC manufacturers into the international auto factory module, and also an important technology to improve the reliability quality of Taiwan IC. In addition, the international auto factory has passed the safety standard (ISO-26262). AEC-Q100 is the basic requirement to pass this standard.

1. List of automotive electronic parts for A.EC-Q100: Automotive disposable memory, Power Supply step-down regulator, Automotive photocoupler, three-axis accelerometer sensor, video jiema device, rectifier, ambient light sensor, non-volatile ferroelectric memory, power management IC, embedded flash memory, DC/DC regulator, Vehicle gauge network communication device, LCD driver IC, Single power Supply differential Amplifier, Capacitive proximity switch Off, high brightness LED driver, Asynchronous switcher, 600V IC, GPS IC, ADAS Driver Assistance System Chip, GNSS Receiver, GNSS front-end amplifier... 

B. Temperature and humidity test conditions: temperature cycle, power temperature cycle, high temperature storage life, high temperature working life, early life failure rate;

2. List of automotive electronic parts for A.AC-Q200: automotive grade electronic components (compliant with AEC-Q200), commercial electronic components, power transmission components, control components, comfort components, communication components, audio components.

B. Test conditions: high temperature storage, high temperature working life, temperature cycle, temperature shock, humidity resistance.

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ESS Environmental Stress Screening Test Chamber

ESS Environmental Stress Screening Test Chamber

The full horizontal air supply system from right to left with large air volume is adopted, so that all specimen cars and specimens on the test are charged and divided, and the heat exchange is completed evenly and quickly.

◆ The utilization rate of test space is as high as 90%

◆ The special design of "uniform horizontal air flow system" of ESS equipment is the patent of Ring measurement.

Patent number: 6272767

◆ Equipped with air volume regulation system

◆ Unique turbine circulator (air volume can reach 3000~ 8000CFM)

◆ Floor type structure, convenient loading and unloading of tested products

◆ According to the special structure of the tested product, the box suitable for installation is used

◆ The control system and refrigeration system can be separated from the box, which is easy to plan or do noise reduction in the laboratory

◆ Adopt cold balance temperature control, more energy saving

◆ Equipment adopts the world's top brand Sporlan refrigeration valve with high reliability and long life

◆ The refrigeration system of the equipment adopts thickened copper pipe

◆ All the strong electric parts are made of high temperature resistant wires, which has higher safety

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Heat Pipe Reliability Test

Heat Pipe Reliability Test

Heat pipe technology is a heat transfer element called "heat pipe" invented by G.M. rover of Los Alamos National Laboratory in 1963, which makes full use of the principle of heat conduction and the rapid heat transfer properties of the refrigeration medium, and transfers the heat of the heating object quickly to the heat source through the heat pipe. Its thermal conductivity exceeds that of any known metal. Heat pipe technology has been widely used in aerospace, military and other industries, since it has been introduced into the radiator manufacturing industry, making people change the design idea of the traditional radiator, and get rid of the single heat dissipation mode that simply relies on high air volume motor to obtain better heat dissipation effect. The use of heat pipe technology makes the radiator even if the use of low speed, low air volume motor, can also get satisfactory results, so that the noise problem plagued by air cooling heat has been well solved, opening up a new world in the heat dissipation industry.

Heat pipe reliability test conditions:

High temperature stress screening test: 150℃/24 hours

Temperature cycling test:

120℃(10min)←→-30℃(10min), Ramp: 0.5℃, 10cycles 125℃(60min)←→-40℃(60min), Ramp: 2.75℃, 10cycles

three-zone thermal shock test chamber

Thermal shock test:

120℃(2min)←→-30℃(2min), 250 cycles

125℃(5min)←→-40℃(5min), 250 cycles

100℃(5min)←→-50℃(5min), 2000 cycles(check once after 200 cycles)

two-zone thermal shock test chamber

High temperature and high humidity test:

85℃/85%R.H./1000 hours

high temperature and high humidity test chamber

Accelerated aging test:

110℃/85%RH/264h

high pressure accelerated aging tester

Other heat pipe test items:

Salt spray test, strength (blasting) test, leakage rate test, vibration test, random vibration test, mechanical shock test, helium combustion test, performance test, wind tunnel test

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How Long Is the Xenon Lamp Weathering Test Chamber Equivalent to a Year of Outdoor Exposure?

How Long Is the Xenon Lamp Weathering Test Chamber Equivalent to a Year of Outdoor Exposure?

How long is the xenon lamp weathering test chamber equivalent to a year of outdoor exposure? How to test out its durability? This is a technical problem, but also a lot of users are concerned about the problem. Today's engineers of Lab Companion are going to explain this problem.

This problem looks very simple, in fact, it is a complex problem.We can not just get a simple number, let this number and the test time of the xenon lamp weathering test chamber to multiply, so as to get the outdoor exposure time, nor is the quality of our xenon lamp weathering test chamber not good enough! No matter how good the quality of the xenon lamp weathering test chamber is, how advanced it is, it is still impossible to find only a number to solve the problem. The most important thing is that the outdoor exposure environment is complex and changeable, affected by many factors, what are the specific?

1. The influence of geographical latitude

2. The influence of altitude

3. The influence of geographical environment when testing, such as wind speed.

4. The impact of the season, winter and summer will be different, summer exposure is 7 times the damage of winter exposure.

5. Direction of the test sample

6. Is the sample insulated or uninsulated? Samples placed on insulators will generally age much faster than those not placed on insulators.

7. Test cycle of xenon lamp weathering test chamber

8. Xenon lamp weathering test chamber operating temperature, the higher the temperature, the faster the aging

9. Testing of special materials

10. Spectrum distribution in the laboratory

xenon lamp weathering test chamber

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Hydrogen Fuel Cell Environmental Simulation Test Scheme

Hydrogen Fuel Cell Environmental Simulation Test Scheme

At present, the economic development model based on the consumption of non-renewable energy based on coal, oil and natural gas has led to increasingly prominent environmental pollution and greenhouse effect. In order to achieve sustainable development of human beings, a harmonious relationship between man and nature has been established. The development of sustainable green energy has become a subject of great concern in the world.

As a clean energy that can store waste energy and promote the transformation from traditional fossil energy to green energy, hydrogen energy has an energy density (140MJ/kg) that is 3 times that of oil and 4.5 times that of coal, and is regarded as a subversive technological direction of the future energy revolution. Hydrogen fuel cell is the key carrier to realize the conversion of hydrogen energy into electric energy utilization. After the goal of carbon neutrality and carbon peak "double carbon" was proposed, it has gained new attention in basic research and industrial application.

Hydrogen fuel cell environmental test chamber of Lab Companion meets: fuel cell stack and module: 1W~8KW, fuel cell engine :30KW~150KW Low temperature cold start test: -40~0℃ Low temperature storage test: -40~0℃ High temperature storage test: 0~100℃.

Introduction of hydrogen fuel cell environmental test chamber

The product adopts functional modular design, explosion-proof and anti-static, and meets the relevant test standards. The product has the characteristics of high reliability and comprehensive safety warning, which is suitable for the test of the reactor and fuel cell engine system. Applicable power up to 150KW fuel cell system, low temperature test (storage, starting, performance), high temperature test (storage, starting, performance), wet heat test (high temperature and humidity

 

Safety parts:

1. Explosion-proof camera: real-time record the complete test situation in the box, easy to optimize or adjust in time.

2. Uv flame detector: high-speed, accurate and intelligent fire detector, accurate identification of flame signals.

3. Emergency air exhaust outlet: exhaust the toxic combustible gas in the box to ensure the safety of the test.

4. Gas detection and alarm system: intelligent and rapid identification of combustible gas, automatically generate alarm signals.

5. Double parallel single-pole screw mechanism cold unit: It has the characteristics of classification function, large power, small footprint and so on.

6. Gas precooling system: quickly control the gas temperature requirements to ensure cold start conditions.

7. Stack test rack: stainless steel stack test rack, equipped with water cooling auxiliary cooling system.

 

Fuel cell system test project

Fuel cell system test project

Fuel cell engine air tightness test

Power generation system quality

The volume of the battery stack

Insulation resistance detection

Starting characteristic test

Rated power starting test

Steady-state characteristic test

Rated power characteristic test

Peak power characteristic test

Dynamic response characteristic test

High temperature adaptability test

Fuel cell engine system performance test

Vibration resistance test

Low temperature adaptability test

Starting test (low temperature)

Power generation performance test

Shutdown test

Low temperature storage test

Low temperature start-up and operation procedures

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Reactor and module test items

Reactor and module test items

Routine inspection

Gas leakage test

Normal operation test

Allow working pressure test

Pressure test of cooling system

Gas channeling test

Impact and vibration resistance tests

Electrical overload test

Dielectric strength test

Pressure difference test

Flammable gas concentration test

Overpressure test

Hydrogen leakage test

Freezing/thawing cycle test

High temperature storage test

Air tightness test

Fuel starvation test

Oxygen/oxidizer deficiency test

Short-circuit test

Lack of cooling/impaired cooling test

Penetration monitoring system test

Ground test

Starting test

Power generation performance test

Shutdown test

Low temperature storage test

Low temperature starting test

 

Product applicable standards:

GB/T 10592-2008 High and low temperature test chamber technical conditions

GB/T 10586-2006 Humidity test chamber technical conditions

GB/T31467.3-2015

GB/T31485-2015

GB/T2423.1-2208

GB/T2423.2-2008

GB/T2423.3-2006

GB/T2523.4-2008

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