A Brief Analysis of the Five Characteristics of Walk in Laboratories

The walk-in laboratory has been upgraded on the basis of the original walk-in laboratory, with the characteristics of large testing space and operators being able to operate the test products in the laboratory, providing conditions for temperature and humidity environment testing for industrial manufacturers' batch or large parts, semi-finished products, and finished products. Adopting advanced Chinese LCD display screen touch screen, various complex program settings can be carried out. The program settings adopt dialogue mode, and the operation is simple and fast. It can achieve automatic operation of the refrigeration machine, maximizing automation, and can be equipped with LAN communication interfaces for users to remotely process and centrally control. It can record temperature and temperature parameters for 90 days, and is equipped with a paperless recorder.

5 characteristics of walk-in laboratory

1. Having an extremely wide temperature and humidity control range, it can meet various needs of users. By adopting a unique balanced temperature and humidity control method, a safe and precise temperature and humidity environment can be achieved. Having stable and balanced heating and humidification performance, it can achieve high-precision and highly stable temperature and humidity control.

2. Equipped with high-precision intelligent temperature regulators, temperature and humidity are displayed using LED digital display. Optional temperature and humidity recorder.

3. The refrigeration circuit is automatically selected, and the automatic control device has the performance of automatically selecting and operating the refrigeration circuit according to the set value of temperature, achieving direct start of the refrigeration machine and direct cooling under high temperature conditions.

4. The inner door is equipped with a large observation window, which facilitates the observation of the experimental status of the test samples.

5. Equipped with advanced safety and protection devices - residual current circuit breaker, over temperature protector, phase loss protector, and water cut-off protector.

Dear customer:

Our company has products such as rapid temperature change test chambers, UV accelerated weather resistance testing machines, and temperature and humidity control chambers. You can call our service hotline through our website to learn more about our products. Our pursuit is endless, and we welcome new and old customers to choose their favorite products with confidence. We will be dedicated to serving you!

Basic troubleshooting methods for high and low temperature test chambers:

1、 High and low temperature testing equipment. In high temperature testing, if the temperature change does not reach the test temperature value, the electrical system can be checked and the faults can be eliminated one by one. If the temperature rises slowly, you need to check the air circulation system to see if the regulating baffle of the air circulation is open normally. Otherwise, check the motor of the air circulation

Is the operation normal. If the temperature overshoot is severe, it is necessary to adjust the PID setting parameters. If the temperature rises directly and is protected against overheating, the controller will malfunction and the control instrument must be replaced.

2、 When the high and low temperature test equipment suddenly malfunctions during the test operation, the corresponding fault display prompt and audible alarm prompt will appear on the control instrument. The operator can quickly identify which type of fault it belongs to by referring to the troubleshooting chapter in the operation and use of the equipment, and then ask professional personnel to quickly troubleshoot it to ensure the normal progress of the experiment. Other environmental testing equipment may experience other phenomena during use, so it is necessary to analyze and eliminate them specifically. Regular maintenance and upkeep of environmental testing equipment, regular cleaning of the condenser in the refrigeration system, lubrication of moving parts according to the instructions, and regular maintenance and inspection of the electrical control system are essential tasks

3、 If the low temperature of the high and low temperature testing instrument cannot meet the test indicators, then you need to observe the temperature changes, whether the temperature drops very slowly or there is a trend of temperature recovery after reaching a certain value. The former needs to check whether the working chamber is dried before conducting the low temperature test, so that the working chamber can be kept dry before putting the test sample into the working chamber for further testing. If there are too many test samples placed in the working chamber, which prevent the air in the working chamber from fully circulating, after ruling out the above reasons, you need to consider whether it is a fault in the refrigeration system. In this case, you need to hire professional personnel from the Lab Companion manufacturer for maintenance. The latter phenomenon is caused by poor usage environment of the equipment. The temperature and location of the equipment placement (distance between the box and the wall) must meet the requirements (as specified in the equipment operation instructions).

At present, the company's main products include: high and low temperature test chambers, rapid temperature change test chambers, constant temperature and humidity test chambers, and high and low temperature impact test chambers.

High and low temperature laboratory applications

Can determine whether the reliability and stability performance parameters of the product are qualified. Provide a basis for predicting and improving the quality and reliability of products. Structural characteristics of high and low temperature laboratory:

The high and low temperature laboratory adopts imported advanced temperature and humidity control instruments with PID regulation, fast self-tuning, programmable control of cyclic testing, multiple parameter settings, digital display, and extremely convenient reading;

The refrigeration system adopts an original imported high cooling capacity, high-efficiency maintenance free compressor. Adopting a binary cascade refrigeration method and imported environmentally friendly refrigerant, the cooling capacity is controlled by a servo control valve imported from the United States, saving about 30% energy (compared to our previous products).

The warehouse plate unit combination structure adopts internal stainless steel and external special steel plate spray coating treatment. The internal size can be expanded arbitrarily, and it is easy to disassemble and assemble. It can be customized according to customer requirements to match the site design appearance. Cooperate with customer migration.

A high-temperature resistant sealing strip is installed between the door and the shell of the walk-in constant temperature and humidity testing machine, effectively ensuring the sealing of the working room;

It has the functions of system parameter monitoring and equipment fault protection diagnosis. When there is a fault, it is accompanied by an alarm sound to prompt the fault handling measures, and at the same time, it is recorded in the book, which facilitates maintenance personnel to understand the medical history of the equipment. Improve maintenance quality and equipment stability.

Dear customer:

Hello, our company is a high-quality development team with strong technical strength, providing high-quality products, complete solutions, and excellent technical services to our customers. The main products include walk-in constant temperature and humidity testing chambers, UV accelerated aging testing machines, rapid temperature change testing chambers, walk-in environmental testing chambers, UV aging testers, constant temperature and humidity chambers, etc. Our company adheres to the principle of building a business with integrity, maintaining quality, and striving for progress. With a more determined pace, we continuously climb new heights and contribute to the national automation industry. We welcome new and old customers to confidently choose the products they like. We will serve you wholeheartedly!

How to handle situations encountered during testing in a programmable constant temperature and humidity test chamber

The handling of interruptions in programmable constant temperature and humidity test chambers is clearly defined in GJB 150, which considers three types of interruptions: interruptions within tolerance range, interruptions under under under test conditions, and interruptions under over test conditions. Different situations have different handling methods. For interruptions within the tolerance range, when the test conditions during the interruption period do not exceed the allowable error range, the interruption time should be considered as a part of the total test time; For the interruption of under test conditions, when the test conditions are below the lower limit of allowable error, the predetermined test conditions should be reached again from the point below the test conditions, and the test should be resumed until the predetermined test cycle is completed; Rework the test sample. If the test conditions do not directly affect the interruption of the test conditions, and if the test sample fails in future tests, the test result should be considered invalid. In practical work, we adopt the method of retesting after repairing the test sample for interruptions caused by faults in the test sample; For test interruptions caused by experimental equipment reasons (such as sudden water or power outages, equipment failures, etc.), if the interruption time is not very long (within 2 hours), we usually handle it according to the under test conditions specified in GJB 150. If the time is too long, the test must be redone. The reason for applying the regulation of interrupting the test in this way is determined by the regulation of stable temperature of the test sample.

The determination of the duration at the test temperature in temperature testing is often based on the sample reaching temperature stability at that temperature. Due to differences in product structure, materials, and testing equipment capabilities, the time it takes for different products to reach temperature stability at the same temperature varies. When the surface of the test sample is heated (or cooled) and gradually transferred to the interior of the test sample. This thermal conduction process is a stable thermal conduction process, and there is a time delay when the internal temperature of the test sample reaches thermal equilibrium compared to the time when the surface of the test sample reaches thermal equilibrium. This time delay is the temperature stabilization time. For test samples that cannot measure temperature stability, the minimum required time is specified. That is, when not in operation and unable to measure, the minimum temperature stability time is 3 hours. When in operation, the minimum temperature stability time is 2 hours. In practical work, we use 2 hours as the temperature stability time. When the test sample reaches temperature stability, if the temperature around the test sample suddenly changes, there is a corresponding time delay for the test sample in thermal equilibrium, that is, in a short period of time, the temperature inside the test sample will not change too much.

During the experiment, if there is a sudden water or power outage or equipment failure, we should first seal the test chamber door, because when the test equipment suddenly stops running, as long as the door is sealed, the temperature of the test chamber door will not change sharply. In a short period of time, the temperature inside the test sample will not change too much; Then, determine whether the interruption has affected the test sample. If it has not affected the test sample and the test equipment can resume normal operation in a short period of time, we can continue the test according to the under test condition interruption handling method specified in GJB 150, unless the interruption has caused some impact on the test sample.

Dear customer:

Hello, our company is a high-quality development team with strong technical strength, providing high-quality products, complete solutions, and excellent technical services to our customers. The main products include walk-in constant temperature and humidity testing chambers, UV accelerated aging testing machines, rapid temperature change testing chambers, walk-in environmental testing chambers, UV aging testers, constant temperature and humidity chambers, etc. Our company adheres to the principle of building a business with integrity, maintaining quality, and striving for progress. With a more determined pace, we continuously climb new heights and contribute to the national automation industry. We welcome new and old customers to confidently choose the products they like. We will serve you wholeheartedly!

Introduction to the Solar Simulation Radiation Test Chamber

The solar simulation irradiation test chamber, also known as the "solar radiation protection test device", is divided into three types according to the test standards and methods: air-cooled xenon lamp (LP/SN-500), water-cooled xenon lamp (LP/SN-500), and desktop xenon lamp (TXE). The difference lies in the temperature, humidity, accuracy, time, etc. of the test. It is an indispensable testing instrument in the aging test chamber series.

The test chamber uses an artificial light source combined with a G7 OUTDOOR filter to adjust the system light source to meet the requirements of IEC61646 for solar simulators by simulating the radiation in natural sunlight. The above system light source is used to conduct the IEC61646 photoaging test on the solar cell module, and the temperature on the back of the module needs to be constantly controlled between 50 ± 10oC during the test. Can automatically monitor temperature; Configure a radiometer to control the irradiance of light, ensuring it remains stable at a specified level, while also controlling the testing time.

During the ultraviolet light cycle period in the solar simulation irradiation test chamber, photochemical reactions are usually not sensitive to temperature. But the rate of any subsequent reaction depends on the temperature. The rate of these reactions accelerates with increasing temperature. Therefore, controlling the temperature during UV exposure is crucial. In addition, it is necessary to ensure that the temperature of the accelerated aging test is consistent with the highest temperature at which the material is directly exposed to sunlight. In the solar simulation irradiation test chamber, the UV exposure temperature can be set at any temperature between 50 ℃ and 80 ℃ based on the illuminance and ambient temperature. The UV exposure temperature is adjusted by a sensitive temperature controller and blower system to achieve excellent uniformity in the temperature of this test chamber.

Dear customer:

Hello, our company is a high-quality development team with strong technical strength, providing high-quality products, complete solutions, and excellent technical services to our customers. The main products include walk-in constant temperature and humidity testing chambers, UV accelerated aging testing machines, rapid temperature change testing chambers, walk-in environmental testing chambers, UV aging testers, constant temperature and humidity chambers, etc. Our company adheres to the principle of building a business with integrity, maintaining quality, and striving for progress. With a more determined pace, we continuously climb new heights and contribute to the national automation industry. We welcome new and old customers to confidently choose the products they like. We will serve you wholeheartedly!

Laptop Test Conditions

Notebook computer from the early 12-inch screen evolution to the current LED backlit screen, its computing efficiency and 3D processing, will not be lost to the general desktop computer, and the weight is becoming less and less burden, the relative reliability test requirements for the entire notebook computer is becoming more and more stringent, from the early packaging to the current boot down, the traditional high temperature and high humidity to the current condensation test. From the temperature and humidity range of the general environment to the desert test as a common condition, these are the parts that need to be considered in the production of notebook computer related components and design, the test conditions of the relevant environmental tests collected so far are organized and shared with you.

Keyboard tapping test:

Test one:

GB:1 million times

Key pressure :0.3~0.8(N)

Button stroke :0.3~1.5(mm)

Test 2: Key pressure: 75g(±10g) Test 10 keys for 14 days, 240 times per minute, a total of about 4.83 million times, once every 1 million times

Japanese manufacturers :2 to 5 million times

Taiwan manufacturer 1: more than 8 million times

Taiwan Manufacturer 2:10 million times

Power switch and connector plug pull test:

This test model simulates the lateral forces that each connector can withstand under abnormal usage. General laptop test items: USB, 1394, PS2, RJ45, Modem, VGA... Equal application force 5kg(50 times), up and down left and right pull and plug.

Power switch and connector plug test:

4000 times (Power supply)

Screen cover opening and closing test:

Taiwanese manufacturers: open and close 20,000 times

Japanese manufacturer 1: opening and closing test 85,000 times

Japanese manufacturer 2: opening and closing 30,000 times

System standby and recovery switch test:

General note type: interval 10sec, 1000cycles

Japanese manufacturer: System standby and recovery switch test 2000 times

Common causes of laptop failure:

☆ Foreign objects fall on the notebook

☆ Falls off the table while in use

☆ Tuck the notebook in a handbag or trolley case

☆ Extremely high temperature or low temperature ☆ Normal use (overuse)

☆ Wrong use in tourist destinations

☆PCMCIA inserted incorrectly

☆ Place foreign objects on the keyboard

Shutdown drop test:

General notebook type :76 cm

GB package drop: 100cm

Us Army and Japanese notebook computers: The height of the computer is 90 cm from all sides, sides, corners, a total of 26 sides

Platform :74 cm (packing required)

Land: 90cm (packing required)

TOSHIBA&BENQ 100 cm

Boot drop test:

Japanese :10 cm boot fall

Taiwan :74 cm boot fall

Laptop main board temperature shock:

Slope 20℃/min

Number of cycles 50cycles(no operation during impact)

The U.S. military's technical standards and test conditions for laptop procurement are as follows:

Impact test: Drop the computer 26 times from all sides, sides and corners at a height of 90 cm

Earthquake resistance test :20Hz~1000Hz, 1000Hz~2000Hz frequency once an hour X, Y and Z axis continuous vibration

Temperature test :0℃~60℃ 72 hours of aging oven

Waterproof test: Spray water on the computer for 10 minutes in all directions, and the water spray rate is 1mm per minute

Dust test: Spray the concentration of 60,000 mg/ per cubic meter of dust for 2 seconds (interval of 10 minutes, 10 consecutive times, time 1 hour)

Meets MIL-STD-810 military specifications

Waterproof test:

Us Army notebook :protection class:IP54(dust & rain) Sprayed the computer with water in all directions for 10 minutes at a rate of 1mm per minute.

Dust proof test:

Us Army notebook: Spray a concentration of 60,000 mg/ m3 of dust for 2 seconds (10 minute intervals, 10 consecutive times, time 1 hour)

 

PCT Test Purpose and Application (1)

PCT test is generally known as pressure cooker cooking test or saturated steam test, the most important is to test the product to be tested under harsh temperature, saturated humidity (100%R.H.)[saturated water vapor] and pressure environment, test the high humidity resistance of the test product, for printed circuit board (PCB&FPC), used to carry out material moisture absorption test, high pressure cooking test... For the purpose of the test, if the product to be tested is a semiconductor, it is used to test the moisture resistance of the semiconductor package. The product to be tested is placed in a harsh temperature, humidity and pressure environment. If the semiconductor package is not good, moisture will penetrate into the package along the colloid or the interface between the colloid and the conductor frame. Popcorn effect, open circuit caused by corrosion of dynamic metallized area, short circuit caused by contamination between package pins... And other related issues.

Pressure Digester test (PCT) Structure:

The test chamber consists of a pressure vessel, including a water heater that can produce a 100% (wetting) environment. The different failures of the product to be tested after PCT test may be caused by a large amount of water vapor condensation and penetration.

Bathtub curve:

Bathtub curve (Bathtub curve, failure period), also known as bathtub curve, smile curve, mainly shows the failure rate of the product in different periods, mainly including early death period (early failure period), normal period (random failure period), wear period (degradation failure period), according to the reliability test box of environmental test. It can be divided into screening test, accelerated life test (durability test) and failure rate test. "Test design", "test execution" and "test analysis" should be considered as a whole when conducting reliability tests.

Common failure periods:

Early failure (early death, Infant Mortality Region) : imperfect production, defective materials, unsuitable environment, imperfect design. Random failure period (normal period, Useful Life Region) : external shock, misuse, changes in environmental conditions fluctuations, poor compression performance. Degradation failure period (Wearout Region) : oxidation, fatigue aging, performance degradation, corrosion.

Environmental stress and failure diagram description:

According to the statistical report of Hughes Airlines, the proportion of environmental stress caused by electronic products failure, height accounted for 2%, salt spray accounted for 4%, dust accounted for 6%, vibration accounted for 28%, and temperature and humidity accounted for up to 60%, so the impact of electronic products on temperature and humidity is particularly significant, but due to the traditional high temperature and humidity tests (such as: 40℃/90%R.H., 85℃/85%R.H., 60℃/95%R.H.) takes a long time, in order to speed up the material's hypersonic rate and shorten the test time, accelerated test equipment (HAST[High accelerated life testing machine], PCT[pressure pot]) can be used to carry out relevant tests. It is also called (degenerate failure period, wear period) test.

PCT Test Purpose and Application (2)

θ 10℃ rule:

When discussing product life, the expression of [θ10℃ rule] is generally used, and a simple explanation can be expressed as [10℃ rule], when the ambient temperature rises by 10℃, the product life will be reduced by half; When the ambient temperature rises by 20 ° C, the product life will be reduced to a quarter. This rule can explain how the temperature affects the life of the product (failure), the opposite product reliability test, can also be used to increase the ambient temperature to accelerate the failure phenomenon, a variety of accelerated life aging tests.

Causes of failure caused by moisture:

Water vapor infiltration, polymer material depolymerization, reduced polymer bonding ability, corrosion, cavitation, wire solder joint detachment, leakage between leads, wafer and wafer bonding layer detachment, pad corrosion, metallization, or short circuit between leads. Effect of water vapor on the reliability of electronic packaging: corrosion failure, delamination and cracking, changing the properties of plastic sealing materials.

PCT failure mode for PCB:

Blister, Crack, SR de-lamination.

PCT testing of semiconductors:

PCT is mainly to test the moisture resistance of semiconductor packaging, the product to be tested is placed in a harsh temperature and humidity and pressure environment test, if the semiconductor packaging is not good, moisture will penetrate into the package along the colloidal or colloidal and wire frame interface into the package, common reasons for installation: Popcorn effect, open circuit caused by corrosion of dynamic metallized area, short circuit caused by contamination between package pins... And other related issues.

PCT reliability assessment for IC semiconductors:

DA Epoxy, wire frame material, sealing resin corrosion failure and IC: corrosion failure (water vapor, bias, impurity ions) will cause electrochemical corrosion of IC aluminum wire, resulting in open circuit and migration growth of aluminum wire.

Failure phenomena caused by moisture corrosion of plastic-sealed semiconductors:

Because aluminum and aluminum alloys are cheap and simple to process, they are usually used as metal wires for integrated circuits. From the beginning of the integrated circuit molding process, water and gas will penetrate through epoxy resin to cause corrosion of aluminum metal wires and thus open circuit phenomenon, which becomes the most headache for quality management. Although various efforts have been made to improve product quality through various improvements, including the use of different epoxy resin materials, improved plastic sealing technology and the improvement of inactive plastic sealing film, with the rapid development of miniaturization of semiconductor electronic devices, the corrosion problem of plastic sealed aluminum metal wire is still a very important technical topic in the electronics industry.

Corrosion process in aluminum wire:

① Water permeates into the plastic sealing shell → moisture permeates into the gap between the resin and the wire

② Water permeates the surface of the wafer to cause aluminum chemical reaction

Factors that accelerate aluminum corrosion:

① The connection between the resin material and the wafer frame interface is not good enough (due to the difference in expansion rate between various materials)

② When packaging, the packaging material is contaminated with impurities or impurity ions (due to the appearance of impurity ions)

③ The high concentration of phosphorus used in the inactive plastic encapsulation film

(4) Defects in inactive plastic encapsulation film

The Popcorn Effect:

The original refers to the IC encapsulated in the plastic outer body, because the silver paste used in the wafer installation will absorb water, once the plastic body is sealed without prevention, when the downstream assembly and welding encounter high temperature, the water will burst due to the vaporization pressure, and it will also emit a sound like popcorn, so it is named, when the absorbed water vapor content is higher than 0.17%, The [popcorn] phenomenon will occur. Recently, P-BGA packaging components are very popular, not only the silver glue will absorb water, but also the substrate of the serial board will absorb water, and the popcorn phenomenon often occurs when the management is not good.

 

 

 

 

PCT Test Purpose and Application (3)

The way water vapor enters the IC package:

1. Water absorbed by IC chip and lead frame and silver paste used in SMT

2. Moisture absorbed in the plastic sealing material

3. The device may be affected when the humidity in the plastic sealing room is high;

4. After the encapsulation of the device, water vapor permeates through the plastic sealant and the gap between the plastic sealant and the lead frame, because there is only a mechanical combination between the plastic and the lead frame, so there is inevitably a small gap between the lead frame and the plastic.

Note: As long as the gap between the sealant is greater than 3.4*10^-10m, water molecules can pass through the sealant protection Note: The airtight package is not sensitive to water vapor, generally do not use accelerated temperature and humidity test to evaluate its reliability, but to measure its air tightness, internal water vapor content, etc.

PCT test description for JESD22-A102:

It is used to evaluate the integrity of non-airtight packaged devices against water vapor in water vapor condensation or saturated water vapor environments. The sample is placed in a condensed, high-humidity environment under high pressure to allow water vapor to enter the package, exposing weaknesses in the package such as corrosion of the delamination and metallization layers. This test is used to evaluate new package structures or updates of materials and designs in the package body. It should be noted that there will be some internal or external failure mechanisms in this test that do not match the actual application situation. Since absorbed water vapor reduces the glass transition temperature of most polymer materials, an unreal failure mode may occur when the temperature is higher than the glass transition temperature.

External pin tin short circuit: The ionization effect caused by moisture in the package external pin will cause abnormal growth of ion migration, resulting in short circuit between pins.

Moisture causes corrosion inside the package:

The cracks caused by the moisture through the packaging process bring external ion contamination to the surface of the wafer, and after passing through the surface defects such as: protective layer pinholes, cracks, poor covers... Etc., into the semiconductor original, causing corrosion and leakage current... Such problems, if there is applied bias then the fault is more likely to occur.

PCT test conditions:

(Collate PCB, PCT, IC semiconductor and related materials have relevant test conditions on PCT[steam pot test]) PCT test purpose and application

Precision Oven Manual

Precision ovens are suitable for semiconductor devices in the electronic industry, curing and aging of electronic components, high-temperature precision testing of plastic and rubber, molding processes for telephone handle wires, as well as experimental or workshop production lines in higher education research institutions and industrial and mining enterprises that require high product temperatures.

This instrument is equipped with a two-level temperature control system, dual protection, automatic cut-off for overheating, safe and reliable. The column alarm device has a temperature rise and constant temperature light display. When using this instrument in large quantities in the production workshop, which instrument has reached the constant temperature requirement and which one is still in the heating state can be clearly seen.

The instrument liner is made of high-quality mirror stainless steel, the outer shell is sprayed with plastic, and a safety door lock is installed. The front door adopts a high-temperature resistant glass observation window, which can observe the condition of the test piece inside the box at any time.

Dear customer:

Our company has products such as rapid temperature change test chambers, UV accelerated weather resistance testing machines, and temperature and humidity control chambers. You can call our service hotline through our website to learn more about our products. Our pursuit is endless, and we welcome new and old customers to choose their favorite products with confidence. We will be dedicated to serving you!