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First, confirm whether the power cord is properly installed in accordance with the specifications and effectively connect the ground wire. 2. Confirm whether the dry-ball overtemperature protection switch is set at the maximum temperature of the equipment plus 10~20℃. This is the safe structural range of the equipment. Third, check whether the wet bulb overtemperature protection switch is set at 150℃. Note: The gauze should be removed when the temperature test is only done. If the gauze is operated at a high temperature above 85℃, the gauze should be replaced before the next operation, otherwise it may not be able to absorb water. Please wash your hands before changing the gauze (the gauze is sterilized when it is packed). 1. Is the water storage enough? 2. Is the water tank lid properly covered? 3. Is it clean? (Clean once a month, change the new gauze every three months) Five, confirm 1, wet ball special gauze placement position is correct? (Is it placed in front of the humidity sensor?) 2. Is it wet? (There is water in the water supply tank, if the water level is normal, and the gauze can not be wetted. Please replace the new gauze immediately, usually about every three months to change the new gauze) 3, the water supply tank is normal? 1. Is the water level of the humidifier normal? (3 to 5 minutes after the humidifier water supply, check the water level.) 2, is the water clean during the humidification period? (The humidifier should be drained regularly to keep the device clean) Seven, confirm whether the drain pipe is properly connected?

1. The laboratory shall take the specified proportion of products as test samples according to the [test order]. 2. Indoor temperature: 15 ~ 35℃, relative humidity: no more than 85%R.H. 3. Check the intact state of the test equipment to confirm that the equipment is normal 4. Confirm that the specimen is not "explosive, flammable or highly corrosive" substance. Two, high and low temperature test box test procedure 1. High temperature test 2. Open the main power switch 3. Place the sample in the test box, and the products shall not touch each other; Close the test chamber door. 4. Open the temperature controller and SET the temperature according to the specified requirements, the operation method is as follows: click the "SET" key once, the digital tube in the bottom row of the instrument flashes, use the "" displacement key to move the number, use" "to reduce the key and" "to increase the key to change the set value. After setting, click" set "key twice to return to the measuring surface. The value of T1 is "0", do not change it). 5. Press the start button, then press the time control switch to open the time controller, and set the time according to the specified requirements, the operation method is as follows: Click "◣" on the instrument, and the bottom window will blink with "▲" key. After the time (running time) is finished, click "back" (running key) when the window is no longer blinking, and the instrument will start timing. 6. After the high temperature test is finished, press the stop button, and take out the sample after the temperature drops naturally for 0.5h ~ 1h. 7. The samples taken out are placed in the air, cooled naturally for 1h ~ 2h, and the surface changes of the samples are observed, and recorded in the [high and low temperature test report]. 8. During the test, if the status of the samples needs to be observed, the lamp switch of the test chamber can be turned on, but cannot be pressed for a long time. 9. Low temperature test (after the high temperature test, it must be cooled naturally for 0.5h ~ 1h, and then do the refrigeration test). 10. Open the main power switch. 11. Put the sample in the test box, and the products must not contact each other; close the test box door. 12. Press the temperature control switch to open the temperature controller, and set the temperature according to the specified requirements according to the above method of operating the temperature controller. 13. Press the start button, then press the time control switch to open the time controller, and set the time according to the specified requirements according to the above time control method. 16. After completing the low-temperature operation, press the stop button, and take out the sample after natural cooling for 0.5h ~ 1h. 17. Put the sample out in the air for 1h ~ 2h, observe the changes on the surface of the sample, and fill in the [scrap for high and low temperature test] according to the test requirements. 18. After the test is completed, set the machine at 60℃ for 30 minutes of dry operation. Precautions for high and low temperature test box 1 During the operation, unless absolutely necessary, please do not open the door of the box, otherwise it may lead to the following adverse consequences. • High temperature air flows out of the box ------ Very dangerous • The inside of the door remains hot ---- scald • High temperature air may trigger the fire alarm, resulting in misoperation 2, please note that the machine must be safely grounded to avoid electrostatic induction. 3, avoid closing and then opening the freezer unit within three minutes. 4, if the box is placed hot test, test power control please use external power supply, do not directly use the power supply of the machine. When placing high temperature samples for low temperature tests, it should be noted that the time to open the door should be as short as possible. 5, circuit breaker, overtemperature protector, to provide the safety protection of the machine test products and operators, so please check regularly. 6. It is absolutely prohibited to test explosive, combustible and highly corrosive substances. 7, the lights should be turned on except when necessary, the rest of the time should be turned off. 8. Before doing low temperature, the studio should be dried and dried for 1 hour at 60 ° C. 9, do high temperature test, when the temperature exceeds 55℃ above the case, do not open the cooler. 10, in any section perpendicular to the dominant wind direction, the sum of the test load section area should not be greater than one third of the working section. 11. Please read the instructions carefully before you can operate the machine

1. Reproducibility of environmental conditions The complete and accurate reproduction of environmental conditions existing in nature in the laboratory is elusive. However, within a certain tolerance range, people can accurately and approximately simulate the external environmental conditions experienced by engineering products in the process of use, storage, transportation, etc. This paragraph is summarized in engineering language. The environmental conditions created by the test equipment around the tested product (including the platform environment) should meet the environmental conditions and tolerance requirements specified in the product test specification. For example, the temperature box used for military product testing must not only meet the national military standard GJB150.3-86, GJB150.4-86 according to different types of products in the high temperature, low temperature test value, test time, but also meet the test specifications for the uniformity of temperature field and temperature control accuracy requirements. Only in this way can the reproducibility of environmental conditions in environmental tests be guaranteed. 2. Repeatability of environmental conditions An environmental test equipment may be used for multiple tests of the same type of product, and an engineering product under test may also be tested in different environmental test equipment. In order to ensure the comparability of test results obtained by the same product under environmental test conditions specified in the same test specification, The environmental conditions provided by the environmental test equipment must be reproducible. That is to say, the stress level (such as thermal stress, vibration stress, electrical stress, etc.) applied to the product being tested by the environmental test equipment is consistent with the requirements of the same test specification. The repeatability of the environmental conditions provided by the environmental test equipment is guaranteed by the national metrological verification department after passing the verification procedures formulated by the national technical supervision agency. To this end, it must be required that the environmental test equipment can meet the requirements of the technical indicators and accuracy indicators in the verification regulations, and the use time does not exceed the time limit specified in the verification cycle. Such as the use of very common electric vibration table in addition to meet the exciting force, frequency range, load capacity and other technical indicators, must also meet the requirements of the verification regulations stipulated in the lateral vibration ratio, table acceleration uniformity, harmonic distortion and other accuracy indicators, and the service cycle after each verification is two years, more than two years must be re-verified before it can be put into use. 3. The environmental conditions provided by any environmental test equipment must be observable and controllable, which is not only to limit the environmental parameters within a certain tolerance range, to ensure the reproducibility and repeatability of the test conditions, but also to start from the safety of the product test is necessary. In order to prevent the uncontrolled environmental conditions leading to the damage of the tested products, resulting in unnecessary losses. At present, various test specifications generally require that the accuracy of parameter testing should not be less than one-third of the allowable error of test conditions. 4. Exclusivity of environmental test conditions Each environmental or reliability test has strict regulations on the category, magnitude and tolerance of environmental factors, and unless the environmental factors required by the test penetrate into it, in order to provide an exact basis for judging and analyzing product failure and failure modes during or after the test. Therefore, in addition to providing the specified environmental conditions, the environmental test equipment is not allowed to attach other environmental stress interference to the tested product. For example, the mesa magnetic leakage, the acceleration signal-to-noise ratio, and the total RMS value ratio of the in-band plus speed are limited in the verification regulations of the electric vibration table. Random signal test, harmonic distortion degree and other accuracy indexes are designed to ensure the uniqueness of environmental test conditions. 5. The safety and reliability environmental test of the test equipment, especially the reliability test, the test cycle is long, the object of the test is sometimes high value military products, during the test process, the test personnel often have to operate or test work around the site, so the environmental test equipment must have the characteristics of safe operation, easy operation, reliable use, long working life, etc. To ensure the normal conduct of the test itself. Various protection, alarm measures and safety interlocking devices of test equipment should be perfect and reliable to ensure the safety and reliability of test personnel, tested products and test equipment itself.

First, the reliability test of electronic products: The test conducted to evaluate and analyze the reliability of electronic products is called reliability test. The purpose of the test is usually as follows: 1. In the development stage, it is used to expose the defects in all aspects of the trial-produced products and evaluate the reliability of the products to reach the predetermined indicators. 2. The production stage provides information for monitoring the production process. 3. Carry out reliability evaluation or acceptance of stereotyped products. 4. Expose and analyze the failure laws and related failure modes and failure mechanisms of products under different environmental and stress conditions. 5, in order to improve the reliability of the product, develop and improve the reliability test program, to provide a basis for users to choose products. For different products, in order to achieve different purposes, you can choose different reliability test methods. Reliability tests have a variety of classification methods, such as by environmental conditions, can be divided into simulated tests and field tests under various stress conditions. According to the test project, it can be divided into environmental test, life test, accelerated test and various special tests. According to the purpose of the test, it can be divided into screening test, identification test and acceptance test. If it is divided according to the nature of the test, it can also be divided into two categories: destructive test and non-destructive test. However, the commonly used classification method is to summarize it into five categories, namely, environmental test, life test, screening test, field use test and identification test. 1, environmental test is to assess the adaptability of products under various environmental conditions (vibration, shock, centrifugation, temperature, thermal shock, hot flash, salt spray, low pressure, etc.), is one of the important test methods to evaluate product reliability. 2, the life test is a method to study the life characteristics of the product, which can be carried out in the laboratory to simulate various conditions of use. Life test is one of the most important and basic items in reliability test, which is to investigate the failure (damage) of the product under specific test conditions with time. Through the life test, we can know the life characteristics, failure rule, failure rate, average life and various failure modes that may occur in the course of life test. If combined with failure analysis, the main failure mechanism leading to product failure can be further clarified, which can be used as the basis for reliability design, reliability prediction, improvement of new product quality and determination of reasonable screening and routine (batch guarantee) test conditions. If in order to shorten the test time, the test can be carried out by increasing the stress without changing the failure mechanism, this is the accelerated life test. The reliability level of products can be evaluated by life test, and the reliability level of new products can be improved by quality feedback. 3, screening test is a non-destructive test for all product inspection. The purpose is to select products with certain characteristics or to eliminate early failure products to improve the reliability of the use of products. In the manufacturing process of the product, due to the defects of the material, or due to the process is out of control, so that some products appear so-called early defects or failures, these defects or failures can be eliminated early, you can ensure the reliability level of the product in actual use. 2. The characteristics of reliability screening test are: 1, This test is not sampling, but 100% test. 2, the test can improve the overall reliability level of qualified products, but can not improve the inherent reliability of the product, that is, can not improve the life of each product. 3. The screening effect can not be evaluated simply by the level of the screening elimination rate. The high elimination rate may be due to serious defects in the design, components, and process of the product itself, but it may also be that the screening stress intensity is too high. Low elimination rate, there may be fewer product defects, but it may also be caused by the strength of the screening stress and insufficient test time. Generally, the screening elimination rate Q and screening effect β value are used to evaluate the merits of the screening method: a reasonable screening method should be a large β value and a moderate Q value. The above tests are carried out by simulating the field conditions. Due to the limitations of equipment conditions, the simulation test can often only apply a single stress to the product, and sometimes can also apply double stress, which is very different from the actual use of environmental conditions, so it can not truthfully and comprehensively expose the quality of the product. Field use test is different, because it is carried out in the use of the site, it can most truly reflect the reliability of the product, the data obtained for the reliability of the product prediction, design and guarantee of high value. Field use test plays a more important role in making reliability test plan, verifying reliability test method and evaluating test accuracy. Qualification test is a test performed to evaluate the reliability level of a product. It is a sampling scheme based on sampling theory. Qualification tests are carried out in such a way as to ensure that the producer does not cause the rejection of products of quality conforming to the standards. Third, reliability test method: There are many kinds of reliability test methods for electronic products, and several commonly used methods are introduced below. The first approach is the "test - problem - record - test again" model. This method is to take the preliminarily developed products, through the test found the problem, not to improve immediately, but to record the problem, to be at the end of a test stage and before the next stage, according to the failure mechanism of various failure modes, concentrated improvement, and then the test. Using this test method, the reliability of products will have a great leap forward. This test method is more suitable for a batch of testing machines, there are several problems, one of which is the main problem and the rest of the problem is secondary. The second approach is the "trial-improve-try" model. This method is to expose the weak link of the product through the test, analyze the failure mode and failure mechanism of the product, find out the problem and immediately improve, and then test to confirm the solved problem, so that the reliability of the product is increased. This method in the development stage of electronic products, through the system test, exposed the weak links of the product, according to the specific situation, immediately make the necessary improvement is able to make the reliability of the product has a substantial increase, this method is more suitable for the test only a more common and serious problem situation, more targeted. The third method is the "trial-improve-retest with deferred improvement" model. This method is a combination of method 1 and method 2, through the test found the problem of the product, some improvements in the test in the product problems, some improvements in the test immediately started, some delayed until the end of the test to make improvements. In the test, for the problems that can be improved in time, immediate measures are taken to improve the product and improve the reliability. After the end of the test phase, the delayed problems are improved before the next test begins, and then the test is carried out, so that the reliability of the product is greatly increased. This method is more suitable for several problems in the test, and some problems can be easily improved in the short term, while others need a considerable period of time to improve the comprehensive situation. For the above three methods, electronic products in the development stage, after systematic tests, according to the exposed problems for specific analysis, flexible application. The three methods commonly used in reliability test are often repeated, and the reliability level of a cycle is higher than that of a cycle product. In addition, reliability test should expose the weak links of product production through various aspects of climate environment test, mechanical environment test and human normal use test according to the specific situation, in addition to system test. Through comprehensive scientific analysis and corresponding improvement, the inherent reliability of electronic products can be further improved in the design and development stage. Iv. Concluding remarks The reliability of electronic products is very important and is the main index of product quality. The reliability test of electronic instruments in China follows the standard GB11463 "Reliability Test of Electronic Measuring Instruments". The reliability index of general products in the identification is 300H. If the reliability assessment is carried out according to the commonly used timed truncated test scheme, the total test time should reach about 10000H. Because the electronic products in the design and development stage has experienced many times the "test - analysis - improvement - re-test" reliability growth test process. In this process, due to a series of measures such as improving the design and process measures to eliminate the failure, the occurrence of failure is gradually reduced, and the reliability is increased. The reliability indicators of some electronic products in China are still short of international advanced standards, so we must fully study the relevant standards at home and abroad, and truly evaluate the reliability level in the whole process of product program demonstration, design, production, testing and use, so as to greatly improve the reliability level of electronic products in China and make product quality reach the world advanced level.

1. This product is a non-explosion-proof product, please do not use the constant temperature and humidity machine in the environment with flammable or explosive gas. 2. To prevent electric shock, misoperation, and faults, do not switch on the power supply before the installation and cable connections are complete. 3. In order to avoid machine failure in the constant temperature and humidity test chamber, please provide power supply within the rated voltage range. 4. Please try not to open the test chamber door during the work of the instrument. Opening at high temperature may cause burns to the operator, and opening at low temperature may cause frostbite to the staff in the early morning, and may cause the evaporator to freeze, affecting the refrigeration effect. If you must open, please do some protective work, 5. The ventilation holes of the body should be kept smooth to avoid failure, abnormal operation, reduced life and fire. 6. It is prohibited to disassemble, process, transform or repair the constant temperature and humidity machine without permission, otherwise there will be abnormal action, electric shock or fire risk. 7. If the machine is damaged or deformed when unpacking, do not use it. 8. When the machine is installed and set, be careful not to let dust, thread, iron filings or other things into the machine, otherwise wrong action or failure will occur. 9. Wiring must be correct and grounded. Non-grounding may cause electric shock, misoperation accidents, abnormal display or large measurement errors. 10. Check terminal screws and fixers regularly. Do not use them when they are loose. 11. During the operation of the instrument, the power input terminal cover must be installed on the terminal board to prevent electric shock. 12. When the instrument is in operation, before modifying the setting, signal output, starting, stopping and other operations, safety should be fully considered, and wrong operation will cause damage or failure of the working equipment. 13. Please use a dry cloth to wipe the instrument, do not use alcohol, gasoline or other organic solvents, do not splash water on the instrument, if the instrument is immersed in water, please stop using immediately, otherwise there is the risk of leakage, electric shock or fire. 14. The internal parts of the instrument have a certain life period. In order to continue to use the instrument safely, please carry out regular maintenance and maintenance. When scrapping this product, please treat it as industrial waste.

How to distinguish the fault of temperature control instrument First, the main fault identification method of relay output temperature instrument: 1. Under the premise that the thermocouple or thermal resistance is in good condition and the instrument is connected correctly, the instrument does not heat up after being energized, and even the phenomenon of measuring temperature falling (the set temperature is higher than the prerequisite for measuring temperature). 1) The main control output of the instrument is a relay, and the output of the controlled circuit is an AC contactor (or intermediate relay); First make sure that this output is contact control. Check whether the terminal connection of the main control output is correct. For the instrument whose main control output is reactive, the relay closed end of the main control output should be connected to the wire package end of the AC contactor (intermediate relay), and the other wiring is correct, although the instrument is running, the green indicator is on, but it does not heat up. (Since the meter is a reaction principle). The output relay of the main control of the instrument usually starts. Under the premise that the cable package of the AC contactor (intermediate relay) is connected correctly, the green indicator is on when the instrument is powered on and still does not heat up. Check method: Put the multimeter in the AC voltage and AC 250V gear. Place one meter rod on the normally open terminal of the relay output by the main control of the meter, and place the other meter rod on the middle line of the AC 220V power supply. The multimeter displays whether the AC 220V voltage is present. A) If there is no voltage value: it indicates that one end of the AC contactor (intermediate relay) wire package is not connected to the normal start of the instrument main control output relay, but is connected to the normally closed terminal of the instrument main control output relay, (indicating that there is no voltage input at both ends of the AC contactor or intermediate relay wire package). Check the method, check the AC 220V power supply phase (fire) line has unnecessary wires connected to the middle terminal of the instrument master output relay. Or caused by the internal opening of the wire used. The output relay of the instrument master control does not reverse after being powered on, indicating that the middle end of the instrument master control relay and the normally closed end are bitten. B) If there is about 220V AC voltage, it means that both ends of the AC contactor or intermediate relay wire package are about 220V AC voltage plus. Check method: Check the packet voltage of the AC contactor or intermediate relay is negative 220V. The AC contactor (intermediate relay) will not work if the product requires a packet voltage of AC 380. It is required to replace the AC contact or intermediate relay with the packet voltage of AC 220V. 2) Meet the above requirements, can not work normally. In the case of no power, put the multimeter on the resistance ×10, and press the two meter rods on the two ends of the wire package of the intermediate relay of the AC contactor. If the resistance value is large, it indicates that the coil in the wire package is disconnected or damaged, the AC contactor or the intermediate relay should be replaced. If there is a resistance value, it indicates that there is no iron core in the wire package, which cannot generate electromagnetic suction and cannot work. The AC contactor or intermediate relay should be replaced. 2. During the operation of the instrument, the measuring temperature has been higher than the set temperature, and the green indicator light of the instrument has been extinguished, but the measuring temperature has been rising. Inspection method: 1) The main control output of the table is the relay contact output, and the controlled circuit is an AC contactor or an intermediate relay. (1) When the instrument is not powered on, the multimeter resistance × 1ω is used to detect, and the value of the middle temple and the normal opening resistance of the main control relay of the signal meter is judged. ① If there is resistance, or even a small resistance value, it indicates that the middle end of the relay and the normal beginning of the instrument main control output are bitten by long-term work, and the relay of the instrument main control output should be replaced, and the instrument can only be replaced on the spot. ② If the resistance value is large, it indicates that the relay output of the instrument main control is intact, and there may be problems with the AC contactor or intermediate relay in the controlled circuit. Inspection method: Use the multimeter resistance ×1Ω to detect the resistance value of the normal beginning of the AC contactor or intermediate relay. If there is a resistance value, even the resistance value is very small. Ac contactors or intermediate relays often start to die due to long-term work. Only replace the AC contactor or intermediate relay. Conversely the resistance value is very large, said Clear AC contactor or intermediate relay in good condition. (2) When the instrument is powered on, the instrument is in operation, when the measuring temperature is higher than the set temperature, the green indicator light of the instrument is off, and is greater than 10 ° C, put the multimeter on the AC voltage 250V, and use a meter bar in the normal start of the main control relay of the instrument; Another meter bar shows whether there is a voltage value in the midline multimeter of the AC 220V power supply. ① If the AC voltage is still about 220V, it indicates that the main control relay of the instrument is bitten by long-term work, and the instrument should be replaced. ② If there is no voltage value, it indicates that the main control relay of the instrument is in good condition. Using the above check method, use a multimeter to check whether there is a voltage value at the outlet of the AC contactor or intermediate relay, and another meter to check whether there is a voltage value at the middle line of the AC 220V power supply. If there is an AC 220V voltage value, it indicates that the AC contact or intermediate relay often starts to work for a long time and dies, and should be replaced. If there is no voltage value, it indicates that the normal opening of the AC contactor and the intermediate relay is intact. Second, SSR(level output) temperature control instrument main fault identification method: 1, the thermocouple or thermal resistance is intact and the instrument wiring is correct under the premise that the instrument does not heat up after power, and even the phenomenon of measuring temperature falling (the set temperature is higher than the measurement temperature prerequisite) the main control output of the instrument is SSR(level) output and the controlled circuit is an external solid-state relay. It should first be understood that when the main control output of the instrument is on, the green indicator is on, the main control output terminal has a 12V level, and when the green indicator is dark, no level or OV. Inspection method: 1) In the case of no power, check whether the connection between the instrument master control output and the solid-state relay is correct, and the instrument master control output SSR has (+) and (-) the two small screws on the solid-state relay, or the solid-state relay signal control end (+) and (-) must be connected correctly. At the same time, use the multimeter resistance x 1Ω to measure whether the connection is open. 2) In the case of power, use the multimeter DC voltage 20V, press the two meter rods on the two terminals of the main control output of the instrument (but make sure that the positive and negative), and whether there is 12V DC voltage when the green indicator of the instrument is on. A) If no 12V is measured by the multimeter, the main control output of the meter is faulty. Check whether the model of the instrument is correct and replace the instrument. B) If the multimeter measures 12V, it indicates that there is a problem with the solid-state relay. To replace the solid-state relay, you can also remove the cable connecting to the AC 220V power phase (fire) line at the big screw of the solid-state relay when there is no power supply, and then power on, press the two rods of the multimeter on the two big screws of the solid-state relay with the multimeter resistance ×1. When the green indicator of the instrument is on, the resistance value displayed by the multimeter is very large, which also indicates that the solid-state relay has a problem and should be replaced. On the contrary, when the resistance value displayed by the multimeter is close to 0, it indicates that the solid-state relay is in good condition 2. During the operation of the instrument, the measuring temperature has been higher than the set temperature, and the green indicator light of the instrument has been extinguished, but the measuring temperature has been rising. The main control output of the instrument is SSR(level), and the controlled circuit is a solid-state relay. Inspection method: (1) When the meter is not powered on, put the multimeter resistance ×1KΩ on the gear, and use the two meter rods of the multimeter on the two large screws of the solid-state relay (but remove the connection between the big screw and the layman). ① If the resistance value ∞ displayed on the multimeter is large, the solid-state relay is in good condition when it is cold. ② If the multimeter shows resistance or resistance value is very small, it indicates that the solid-state relay is damaged and should be replaced. (2) When the meter is powered on, when the meter is running, when the measurement temperature is higher than the set temperature and is greater than 10 ° C, the green indicator light of the meter is off, the multimeter is placed on the DC voltage 20V file, and the two meter bars on the multimeter are used at both ends of the main control output of the meter, but the positive and negative values should be made clear whether there is a voltage value displayed on the multimeter. ① If the DC 12V voltage is displayed on the multimeter, it indicates that the meter is faulty and should be replaced. ② If no voltage is displayed on the multimeter, the meter is in good condition. Then check the solid state relays. The method is to remove the connection between the big screw of the solid-state relay and the outside world before the power is turned on. After power, put the multimeter on the resistance ×1KΩ, and use the two meter rods of the multimeter on the two large screws of the solid-state relay. If the multimeter shows a resistance value and the resistance value is very small, it indicates that the solid-state relay is short circuit when it is hot, and the solid-state relay should be replaced. On the contrary, when the resistance value ∞ is large, it indicates that the solid-state relay is in good condition when cold.

1. Water ring vacuum pump maintenance (1) Should always pay attention to the oil level and the cleanliness of the oil, the new pump work 150 hours to change the oil once, after every 2-3 months to change the oil once. If the use conditions are not good, when the vacuum drops, the oil change time can be shortened. (2) The pump and pump room should be kept dry and clean. (3) Often pay attention to the temperature of cooling water and oil, the maximum shall not exceed 85 ° C, the inlet temperature of cooling water shall not exceed 30 ° C, the outlet temperature shall not exceed 5 ° C, and the water quality shall be kept clean. 2. Precautions in daily maintenance (1) Regularly check whether the water ring vacuum pump pipeline and joints are loose. Turn the water ring vacuum pump by hand to see if the water ring vacuum pump is flexible. (2) Add bearing lubricating oil to the bearing body, observe that the oil level should be at the center line of the oil target, and the lubricating oil should be replaced or supplemented in time. (3) Screw the water guide plug of the water ring vacuum pump pump body to inject water (or pulping). (4) Close the gate valve of the outlet pipeline, the outlet pressure gauge and the inlet vacuum gauge. (5) Click the motor and see if the motor steering is correct. (6) Start the motor, when the water ring vacuum pump is running normally, open the outlet pressure gauge and the inlet water ring vacuum pump, and gradually open the gate valve after it shows the appropriate pressure, while checking the motor load. (7) Try to control the flow rate and head of the water ring vacuum pump within the range indicated on the label to ensure that the water ring vacuum pump operates at the highest efficiency point in order to obtain the greatest energy saving effect. (8) During the operation of the water ring vacuum pump, the bearing temperature shall not exceed the ambient temperature of 35C, and the maximum temperature shall not exceed 80C. (9) If the water ring vacuum pump is found to have abnormal sound, immediately stop and check the cause. (10) When the water ring vacuum pump is to stop using, first close the gate valve, pressure gauge, and then stop the motor. (11) Water ring vacuum pump in the first month of work, after 100 hours to replace the oil, after every 500 hours, oil change once. (12) Often adjust the packing gland to ensure that the drip in the packing room is normal (it is appropriate to drip out). (13) Regularly check the wear of the shaft sleeve, and replace it in time after large wear. (14) When the water ring vacuum pump is used in the cold winter season, after stopping, it is necessary to unscrew the water plug in the lower part of the pump body to put the medium away. Prevent frost cracking. (15) If the water ring vacuum pump is out of service for a long time, it is necessary to completely disassemble the pump, dry the water, coat the rotating part and the joint with grease, and store it properly.

First, the vacuum pump degree is not enough Possible cause: insufficient motor power supply resulting in insufficient speed; Insufficient water supply; The clearance between the impeller and the distribution plate is too large; Mechanical seal damage resulting in leakage; Excessive impeller wear; The circulating water cannot be discharged. Elimination method: check whether the power supply voltage is within the rated voltage range of the motor; Increase the water supply (must be controlled within the correct range, otherwise it will lead to motor overload heating); Reduce the gap between the impeller and the distribution plate (generally 0.15-0.20mm); Replace the mechanical seal; Replace the impeller; Check the water outlet pipe. Second, can not start or start loud noise Possible cause: motor supply voltage is insufficient; Motor running without phase; The pump is not used for a long time leading to rust; Suction of debris in the pump; Impeller drag distribution plate. Elimination method: check whether the power supply voltage is too low; Check whether the motor wiring is solid; If the pump does not lead to rust for a long time, you can add rust remover or open the pump cover to remove rust manually; Open the pump cover to remove debris; Adjust the distance between impeller and distribution plate. 3. Motor overheating Possible causes: excessive water supply leads to motor overload; Motor phase missing; The exhaust hole is blocked; The impeller drags other components. Elimination method: reduce the water supply to the normal range (refer to the pump instruction manual for liquid supply); Check whether the wiring is firm; Check the exhaust port; Open pump cover to adjust the clearance between impeller and other components. Four, insufficient flow Possible causes: pipeline leakage; Resistance loss increases; Elimination method: check the mechanical seal at the joint; Check whether pipes and check valves are faulty. Water ring vacuum pump routine maintenance: (1) In normal work should pay attention to check the work and lubrication of the bearing, the temperature (bearing and outer circle) than the ambient temperature is generally 15℃ ~ 20℃ higher than the appropriate, the maximum is not allowed to exceed 30℃ ~ 35℃, that is, the actual temperature of the outer circle of the bearing frame should not exceed 55℃ ~ 60℃; The normal working bearings should be refueled 3 to 4 times a year, the bearings should be cleaned at least once a year, and the lubricating oil should be replaced. (2) In normal work, the packing should be regularly pressed, if the packing can not ensure the required sealing performance due to wear, the new packing should be replaced. If the mechanical seal is used and the leakage phenomenon is found, the dynamic and static ring of the mechanical seal should be checked whether it has been damaged or the auxiliary seal is aging. If the above situation occurs, new parts need to be replaced. (3) When there is a special sound, the pressure plate on the two end covers can be removed to see whether the two ends of the impeller are damaged with the distributor, and the exhaust valve plate can also be checked whether it is normal. Description of other faults of the water ring vacuum pump 1, the cause of the vacuum pump mechanical seal leakage ①, improper mechanical seal disassembly When replacing the non-energy end machine seal, it was found that the sealing O-ring on the moving ring was not properly installed in the assembly. The O-ring washer should have been installed outside the sealing groove on the moving ring seat, and the assembly review found that the O-ring was not so installed, but was incorrectly installed outside the spring positioning plate, so that the spring was deformed, and the axial static seal was completely unable to play the role of leakage. ②, the machine seal ice water pressure is too large The binding force of the book cover is imposed by the spring on the moving ring. When the icing water pressure is too large, the water pressure will act on the dynamic ring, because the static ring is raw and easy, so the water pressure will stimulate the dynamic ring, compress the spring to the same position of the static ring, thus weakening or the adhesion force of the static and dynamic ring surface, and attract the dense book cover leakage. After the maintenance, the energy end machine is sealed into the frozen water for leakage test. The inlet valve is opened 2/3 times, and the machine seal is complete without leakage. When the water valve is opened more than 2/3, the machine seal leaks. The three parties (maintenance party, iron oxide mechanics, Sichuan Dayu machine seal building factory) preliminarily concluded that it was caused by excessive water pressure, and proposed to start operation after the motor training and repair, and further trace and find out the real cause of its leakage. ③, static ring close book cover cracked This is an important cause of the previous replacement of the pump seal leakage. The energy end and non-energy end machine seals are disassembled on the same shaft, the impeller device is beside the shaft, and the bearings at both ends of the shaft are supported vividly. When the energy end or non-energy end machine seal is replaced jointly, the bearing (bearing seat) of the corresponding end must be assembled first to store the old machine seal and install the new machine seal, and at this time, so the shaft and impeller gravity, the impeller and shaft tube supported by one end of the bearing are protected to collapse, and the shaft is skewed to the bearingless end. Because the static ring is not removed on the pump end cover with bolts, and the moving ring is vivid on the shaft and the shaft together, in addition, because the gap between the inner ring of the static ring and the shaft is very small, when the shaft is collapsed and skewed, it will cause: a, the static ring of the unremoved end absolute displacement, so that the static ring close to each other pheasant extrusion, resulting in fragmentation; b, the shaft is indirectly pressed on the inner ring of the undismantled static ring, causing the static ring cover to break or break. After the understanding and synthesis of the previous number of replacement operations, the cause of good replacement at one end and the leak of the seal at the other end is caused by the above components. In fact, our operators have also contemplated a problem, but the step is not correct: the previous number of changes are the use of bamboo melon hanging the shaft of the disassembly end to prevent the swing of the shaft from high and low, and the theoretical operation has confirmed that this lifting step is a big mistake, especially not practical for this kind of heavy real air pump seal device. The reason is that the tension of the lifting point and the bamboo melon is difficult to completely grasp, and it is difficult to prevent the height and left and right of the shaft from swinging. 2. The cause of the distress of the vacuum pump ①, the positioning bearing clearance at both ends of the pump is not adjusted. The bearings at both ends of the pump are adopted double row tapered roller bearings, double row tapered roller bearing two rows of inner ring and outer ring is conical contact, the inner ring can be combined from the outer ring into. There is a bearing clearance adjustment ring between the two columns of inner rings, that is, the original clearance of the bearing is controlled by the separation ring between the two columns of inner rings, and the clearance of the normal bearing has been adjusted when it is left the factory. The bearing is disassembled on the shaft, one of the two columns of inner rings is on the shoulder of the shaft, and the other column is locked on the shaft by the locking back cap. After locking, the two columns of inner rings and spacer rings do not need to be tightly connected together to rotate together with the shaft, and the outer ring is tightly matched with the bearing box. Then, when the gap adjustment ring thickness is less than the original thickness, when the back cap is locked, the inner ring and the outer ring in the two rows produce an inimical force extrusion, so that the bearing rotation is difficult or helpless. 2, bearing inner ring is not installed in place The bearing inner ring is not installed in place will also produce the problem described in 1) below, the cause is that the absolute axis of the inner and outer ring is misaligned forward and back, resulting in one of the two columns of the inner ring and the outer ring are squeezed by the same force. When removing the energy end bearing, it was found that the shaft surface of the bearing position of the device had a large eat mark, and it was concluded that the inner ring of the bearing was not completely top to the shaft shoulder, which was an important cause of the difficulty of the turning. (3) The clearance between the impeller and the pump is not adjusted The clearance between the impeller of the water ring vacuum pump and the two ends of the pump body is adjusted by moving the bearing seats at both ends. The adjustment step is to add or remove a gasket between the bearing seat and the support positioning surface on which the bearing seat is installed. ④, the machine seal dynamic ring close book cover is broken after each other card.

Oil-type vacuum pump is referred to as oil-type pump, oil-type vacuum pump is also known as oil-sealed rotary vane vacuum pump or oil-sealed mechanical pump. Therefore, the oil vacuum pump is the vacuum equipment product that uses the vacuum pump oil as the medium to seal the pump, so the maintenance of the oil pump should consider the replacement of the medium oil and the use of precautions. Oil seal rotary vane vacuum pump is the most widely used oil seal single stage rotary vane vacuum pump, followed by water ring vacuum pump -2X double stage vacuum pump, this paper mainly introduces the maintenance of oil pump and vacuum pump oil replacement and use of several points for attention. (A) The use of oil-sealed rotary vane vacuum pump need to pay attention to the following issues: 1. Mechanical vacuum pumps such as rotary vane vacuum pumps should be installed in a clean and clean environment, and the temperature should be within the range of 15 to 40 degrees. 2 When the rotary vane vacuum pump is connected to the power supply for the first time, check the steering of the motor. It is consistent with the steering of the rotor in the pump. Otherwise, the power supply should be stopped immediately to change the connection position of the two phases. 3. Before starting the vacuum pump each time, apply hand rotation or intermittent start several times to remove the oil in the rotary vane vacuum pump from the vacuum pump to reduce the resistance during starting. 4. When the vacuum pump needs to be stopped after use, the vacuum pump should be discharged into the atmosphere. Avoid pumping oil back into the system; For large mechanical vacuum pump, first put the atmosphere and then stop the pump. The use of electromagnetic reading with gas discharge is a better measure to ensure that the vacuum pump is deflated when the pump is stopped. 5. The oil temperature shall not exceed 75 degrees when the vacuum pump is running, and some real pumps should be cooled by water cooling to ensure that they have better parts. 6. It should be best to install a precision filter at the inlet of the real pump to eliminate oil vapor and not make it pollute the entire system. Precision filter for removing condensable steam. When removing corrosive gases, a corrosion-resistant mechanical vacuum pump should be used and equipped with a trap to eliminate the corrosion of corrosive gases on the vacuum pump and extend the service life of the vacuum pump. In order to ensure that the rotary vane vacuum pump has better working performance and longer life, the maintenance and maintenance matters should be paid attention to during the use of the mechanical pump: In the process of operation, the oil in the pump should be kept not lower than the standard line on the vacuum pump oil label. When refueling, do not mix different grades and types of vacuum pump oil. Replace the vacuum pump oil regularly, generally 3 to 6 months to replace once, so as not to increase the difficulty of vacuum pump maintenance. The reason of vacuum pump failure and the method of elimination 1. The vacuum is not high [1] The temperature of the vacuum pump is too high, 1. The temperature of the pumped gas is too high. The gas should be cooled and then enter the vacuum pump, 2. The suction of hard objects will make the vacuum pump body wear. The vacuum pump should be disassembled to remove the hard objects and repair or replace the scratched parts. 3. The vacuum pump is not enough water flow. 4. Improper assembly will make the rotor axis displace, resulting in one-sided wear. Should be disassembled, inspected and reassembled. (2) The vacuum pump oil has a problem, 1. The oil level is too low. Should add enough oil to show the center line of the oil label, 2. The oil is stained and the oil quality deteriorates. Should be replaced with new oil, 3. The brand of oil does not match. The specified brand of vacuum pump oil should be changed, 4. The oil circuit is blocked, and the appropriate amount of oil is not maintained in the vacuum pump chamber. Check the oil inlet of the oil circuit and the oil valve to keep the oil circuit unblocked. (3) Vacuum pump itself leakage: 1. Seal leakage. Check the sealing conditions of all sealing parts and replace the damaged sealing ring. 2. The gasket of the gas ballast valve is damaged or not tightened. Replace the gasket and tighten the gas ballast valve; 3. The exhaust valve plate is damaged and the seal is not good. The air valve disc should be replaced; 4. When the diaphragm is pressed into the vacuum pump, the interference is too large, resulting in the deformation of the vacuum pump cavity and air leakage. The vacuum pump cavity should be trimmed or replaced. 5. Due to the poor oil seal of the end face of the vacuum pump, air leakage is caused. The end cover should be opened to check whether there is debris or irregularity, and cleaned or repaired. (4) The rotor spring is deformed or broken and the spinning motion is not working. The spring deformation should be repaired or replaced to make the rotor product fit well. (5) The air inlet filter is blocked. The filter should be removed, cleaned, and then installed, (6) Excessive clearance caused by poor processing or wear. The matching gap between the vacuum pump chamber, rotor, rotary plate and end cover plate should be checked, and repaired or replaced according to the specified accuracy requirements. (7) Friction heat during vacuum pump operation. The temperature rise is too high, so that the vacuum pump oil becomes thin, the sealing is poor. Cooling water or electric fan should be used to cool down, at the same time, check the clearance of relevant parts and repair or replace them according to the specified accuracy requirements. Motor, vacuum pump abnormal operation, motor overload operation, vacuum pump in the operation of abnormal noise, noise, rotation difficulties or "stuck" phenomenon. (1) Vacuum home temperature is too high, can refer to 1 paragraph (1) treatment, (2) The spring is deformed or broken, so that the rotating plate is stressed unevenly and sends out an impact sound; The spring should be replaced. (3) improper assembly, resulting in single-side wear, should be reassembled; (4) The filter screen is damaged, metal chips, glass chips, etc., fall into the vacuum pump, making the operation of obstacles. The vacuum pump should be removed to check, remove debris, repair or replace worn parts, and install the filter. (5) The vacuum pump cavity is seriously polluted, resulting in corrosion of parts. Should remove vacuum pump please wash, remove rust class, and change oil, (6) The vacuum pump oil becomes milky. Viscosity increases. Should be replaced with a new vacuum pump oil, (7) Vacuum pump chamber, shaft and shaft sleeve are too tight, tight into poor lubrication. The oil circuit should be reassembled and dredged and adjusted to strengthen lubrication (8) The vacuum pump cavity is seriously polluted, resulting in corrosion of parts. Vacuum pump should be removed, please wash, remove rust spots, and change the oil, (9) The motor is faulty and produces noise. The motor should be serviced or the bearing should be lubricated with butter.

First, the basis for equipment selection: the types of natural environmental factors and induced environmental factors existing on the earth's surface and atmospheric space, at present, it is not possible to calculate an exact number, which has a greater impact on the use and life of engineering products (equipment) more than a dozen kinds of factors. Engineers who are engaged in the research of environmental conditions of engineering products summarize the environmental conditions that exist in nature and induced by human activities into a series of test standards and norms to guide the environmental and reliability tests of engineering products. For example, to guide military products to conduct environmental tests GJB150 - the People's Republic of China's national military standard "Military equipment Environmental test Method", to guide electrical and electronic products to conduct environmental tests GB2423 - the People's Republic of China's national standard "Electrical and electronic products Environmental Test Method Guide" and so on. Therefore, the main basis for our selection of environmental and reliability test equipment is the test specifications and test standards of engineering products. Secondly, in order to standardize the tolerance of environmental test conditions in test equipment and ensure the control accuracy of environmental parameters, the national technical supervision agency and various industrial departments have also formulated a series of verification regulations for environmental test equipment and testing instruments. For example, the national standard of the People's Republic of China GB5170 "Basic parameter Verification method of environmental testing equipment for electrical and electronic products", and the JJG190-89 "Trial Verification Regulations of Electric Vibration test Bench System" promulgated and implemented by the State Bureau of Technical Supervision. These verification regulations are also an important basis for selecting environmental and reliability test equipment, and test equipment that does not meet the requirements of these verification regulations is not allowed to be put into use. Second, the basic principles of equipment selection: The selection of environmental and reliability test equipment should follow the following five basic principles: 1, the reproducibility of environmental conditions in the laboratory complete and accurate reproduction of the environmental conditions existing in nature is an elusive thing. However, within a certain tolerance range, people can accurately and approximately simulate the external environmental conditions experienced by engineering products in the process of use, storage, transportation, etc. This paragraph is summarized in engineering language, that is, "the environmental conditions created by the test equipment around the tested product (including the platform environment) should meet the environmental conditions and tolerance requirements specified in the product test specification." For example, the temperature box used for military product testing should not only meet the requirements of the national military standard GJB150.3-86, GJB150.4-86 according to different uniformity and temperature control accuracy. Only in this way can the reproducibility of environmental conditions in environmental tests be guaranteed. 2, repeatability of environmental conditions An environmental test 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 test equipment, in order to ensure that the same product in the same test specification under the environmental test conditions of the test results are comparable, The environmental conditions provided by the environmental test equipment must be reproducible. That is to say, the stress level (such as thermal stress, vibration stress, electrical stress, etc.) applied to the product being tested by the environmental test equipment is consistent with the requirements of the same test specification. The repeatability of the environmental conditions provided by the environmental test equipment is guaranteed by the national metrological verification department after passing the verification procedures formulated by the national technical supervision agency. To this end, it must be required that the environmental test equipment can meet the requirements of the technical indicators and accuracy indicators in the verification regulations, and the use time does not exceed the time limit specified in the verification cycle. Such as the use of very common electric vibration table in addition to meet the exciting force, frequency range, load capacity and other technical indicators, but also must meet the requirements of the verification regulations stipulated in the lateral vibration ratio, table acceleration uniformity, harmonic distortion degree and other accuracy indicators, and the service cycle after each verification is two years, more than two years must be re-verified before it can be put into use. 3. The environmental conditions provided by any environmental test equipment must be observable and controllable, which is not only to limit the environmental parameters within a certain tolerance range, to ensure the reproducibility and repeatability of the test conditions, but also to start from the safety of the product test is also necessary. In order to prevent out-of-control environmental conditions leading to damage to the tested products, bringing unnecessary losses. At present, various test specifications generally require that the accuracy of parameter testing should not be less than one-third of the error allowed by the test conditions. 4. Exclusion of environmental test conditions Each time an environmental or reliability test is carried out, there are strict regulations on the category, quantity value and tolerance of environmental factors, and unless the environmental factors required by the test penetrate them, in order to provide an exact basis for judging and analyzing product failure and failure mode during the test or after the test. Therefore, in addition to providing the specified environmental conditions, the environmental test equipment is not allowed to attach other environmental stress interference to the tested product. For example, the mesa magnetic leakage, the acceleration signal-to-noise ratio, and the total RMS value ratio of the in-band plus speed are limited in the verification regulations of the electric vibration table. Random signal test, harmonic distortion degree and other accuracy indexes are designed to ensure the uniqueness of environmental test conditions. 5, the safety and reliability of the test equipment environmental test, especially the reliability test, the test cycle is long, the test object is sometimes high value military products, during the test process, the test personnel often have to operate around the site patrol or test work, so the environmental test equipment must have the characteristics of safe operation, easy operation, reliable use, long working life, etc. To ensure the normal conduct of the test itself. Various protection, alarm measures and safety interlocking devices of test equipment should be perfect and reliable to ensure the safety and reliability of test personnel, tested products and test equipment itself. 1, volume selection When the tested product (components, components, components or whole machine) is placed into the climate environment chamber for test, in order to ensure that the atmosphere around the tested product can meet the environmental test conditions specified in the test specification, the working size of the climate chamber and the outer size of the tested product should follow the following provisions: 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). It is recommended not to use more than 10% of the products that heat up in the test. b) The ratio of the upwind fault area of the tested product to the total area of the test chamber on this section is not greater than (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 at least 100 ~ 150mm (150mm is recommended). The above three provisions are actually interdependent and unified. Taking 1 cubic meter cube box as an example, the area ratio of 1: (0.35 ~ 0.5) is equivalent to the volume ratio of 1: (0.207 ~ 0.354). 100 ~ 150mm from the wall of the box is equivalent to a volume ratio of 1: (0.343 ~ 0.512). In summary, the above three points stipulate that the working chamber volume of the climate environment test chamber should be at least 3 to 5 times the outer volume of the tested product. The reasons for this provision are as follows: (1) After the test piece is placed into the box, the smooth channel is squeezed, and the narrowing of the channel will lead to an increase in the airflow velocity. Accelerate the heat exchange between the air flow and the part under test. This is inconsistent with the reproduction of environmental conditions, because in the relevant standards for environmental tests involving temperature, it is stipulated that the air flow rate around the test sample in the test box should not exceed 1.7m/s, in order to prevent the test sample and the surrounding atmosphere from producing unrealistic heat conduction. When the average wind speed in the test box is 0.6 ~ 0.8m/s, not more than 1m/s, when the space and area ratio specified in the requirements of a) and b) is met, the wind speed of the flow field may increase by (50 ~ 100) %, and the average maximum wind speed is (1 ~ 1.7) m/s. Meet the requirements specified in the standard. If the volume of the test piece or the windward section area is increased without restriction in the test, the actual wind speed will increase to exceed the maximum wind speed specified in the test standard, and the validity of the test results will be doubted. (2) The precision indicators of environmental parameters in the working chamber of the climate chamber (such as temperature, humidity, salt spray settlement rate, etc.) are the results of detection in the no-load state. Once placed in the tested part, the uniformity of environmental parameters in the working chamber of the test chamber will be affected, and the larger the space occupied by the test part, the more serious the impact will be. The measured test data show that the temperature difference between the windward side and the leeward side in the flow field can reach 3 ~ 8℃, and it can reach more than 10℃ when it is severe. Therefore, it is necessary to meet the two requirements of a] and b) as far as possible to ensure the uniformity of environmental parameters around the tested product. (3) According to the principle of heat conduction, the temperature of the air flow near the box wall is usually 2 ~ 3 ° C different from the center temperature of the flow field, and may reach 5 ° C at the upper and lower limits of high and low temperatures. The temperature of the box wall and the temperature of the flow field near the box wall differ 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 above, therefore, the space within the distance from the box wall (100 ~ 150mm) is unusable space. 2, the choice of temperature range At present, the range of foreign temperature test chambers is generally -73 ~ +177 ° C, or -70 ~ +180 ° C. Most domestic manufacturers are generally -80 ~ +130 ° C, -60 ~ +130 ° C, -40 ~ +130 ° C, and also have high temperatures to 150 ° C. These temperature ranges can usually meet the needs of the vast majority of domestic military and civilian product temperature tests, unless there are special needs, such as the installation location near the engine and other heat sources of the product, can not blindly increase the temperature limit. Because the higher the upper limit temperature, the greater the temperature difference between the inside and outside the box, the worse the uniformity of the flow field inside the box. The smaller the available studio space. On the other hand, the higher the upper temperature value, the higher the heat resistance requirements of the insulation materials (such as glass wool, etc.) in the interlayer of the box wall. The sealing requirements of the box are also higher, so that the production cost of the box increases. 3, the selection of humidity range at home and abroad, the humidity index given by the environmental test box is mostly 20 ~ 98%RH or 30 ~ 98%RH, if the wet heat test box does not dehumidification system, the humidity range is 60 ~ 98%, this type of test box can only do high humidity test, but its price is much lower. It is worth noting that the corresponding temperature range should be indicated after the humidity indicator, or the lowest dew point temperature should be given. Because the relative humidity is directly related to temperature, for the same absolute moisture content, the higher the temperature, the smaller the relative humidity, such as the absolute moisture content is 5g/Kg (refers to 1 kg of dry air contains 5 grams of water vapor), when the temperature is 29℃, the relative humidity is 20%RH, when the temperature is 6℃, the relative humidity is 90%RH, when the temperature drops below 4℃, the relative humidity is 20%RH. If the relative humidity exceeds 100%, there will be condensation in the box. To achieve high temperature and high humidity, it is only necessary to spray steam or atomized water droplets into the box air for humidification. Low temperature and low humidity is relatively difficult to control, because the absolute moisture content at this time is very low, sometimes much lower than the absolute moisture content in the atmosphere, the need to dehumidify the air flowing in the box, so that the air becomes dry. At present, most of the temperature and humidity boxes at home and abroad use the principle of refrigeration dehumidification, which is to add a group of refrigeration light tubes in the air preconditioning room of the box. When the wet air passes through the cold tube, its relative humidity will reach 100%RH, because the air is saturated on the light tube condensation, so that the air becomes drier. This dehumidification method can theoretically reach the dew point temperature below zero, but when the cold point surface temperature reaches 0℃, the dew droplets on the surface of the optical tube will freeze, thus affecting the heat exchange on the surface of the optical tube, so that the dehumidification ability is reduced. And because the box can not be absolutely sealed, the wet air in the atmosphere will penetrate into the box, so that the dew point temperature rises. On the other hand, the wet air flowing between the optical tube only reaches saturation at the moment of contact with the optical tube (cold point) and precipitated water vapor, so this dehumidification method is difficult to make the dew point temperature in the box below 0 ° C. The actual lowest dew point temperature is 5 ~ 7℃. The dew point temperature of 5℃ is equivalent to the absolute moisture content of 0.0055g/Kg, corresponding to the relative humidity of 20%RH temperature of 30℃. If the required temperature is 20 ° C into the relative humidity of 20%RH, at this time the dew point temperature is -3 ° C, the use of refrigeration dehumidification is very difficult, must use the air drying system to achieve. 4, the choice of control mode temperature, humidity test box has a constant test box, alternating test box two cases. Ordinary high and low temperature test chamber generally refers to a constant high and low temperature test chamber, and its control mode is: set a target temperature, and the test chamber has the ability to automatically maintain a constant temperature to the target temperature point. The control mode of the constant temperature and humidity test chamber is similar, setting a target temperature and humidity point, 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 the ability to set one or more 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 rate of heating and cooling within the range of the maximum temperature rise and cooling rate, that is, the rate of heating and cooling can be controlled according to the slope of the set curve. Similarly, the high and low temperature alternating wet heat test chamber also has a preset temperature, humidity curve, and the ability to control according to the preset. Of course, the alternating test box has the function of a constant test box, but the manufacturing cost of the alternating test box is higher, because the alternating test box needs to be configured with a curve automatic recording device, program control instrument, and must solve the problem of opening the refrigerator when the temperature of the test box is higher in the chamber, so the price of the alternating test box is generally more than 20% higher than the price of the constant test box. Therefore, we should be realistic to the needs of the test method as a starting point, choose a constant test chamber or an alternating test chamber. 5, the choice of temperature change rate ordinary high and low temperature test chamber has no cooling speed index, the time from the ambient temperature to the nominal minimum temperature is generally 90 ~ 120min. The high and low temperature alternating test chamber and the high and low temperature alternating wet and heat test chamber have the requirements of changing temperature speed, and the changing temperature rate is generally required to be 1℃/min, and the speed can be adjusted within the range of this rate. The rapid temperature change test chamber has a faster temperature change rate, and the heating and cooling rates can reach 3 ° C /min ~ 15 ° C /min, and the heating and cooling rates can even reach more than 30 ° C /min in some temperature segments. The temperature range of the rapid temperature change test chamber of various specifications and speeds is generally the same, that is, -60 ~ +130℃, but the temperature change range of the examination cooling speed is not the same, according to the different test requirements of the test, the temperature change range of the rapid temperature change test chamber is -55 ~ +80℃, and some are -40 ~ +80℃. There are two formulations for the temperature change rate of the rapid temperature change test chamber, one is the average rise and fall rate of the whole process, and the other is the linear rise and fall rate (in fact, the average speed every 5 minutes). The average speed of the whole process is the ratio of the difference between the highest temperature and the lowest temperature in the temperature range of the test chamber to the time. At present, the technical parameters of variable temperature rate provided by foreign environmental test equipment manufacturers all refer to the average speed of the whole process. Linear rising and cooling rate refers to the temperature change rate that can be guaranteed in any 5min period. In fact, for the rapid temperature change test chamber, the most difficult and critical part of ensuring the linear rise and cooling speed is the cooling rate that the test chamber can achieve within a period of 5 min at the end of the cooling section. From a certain point of view, the linear rising and cooling speed (the average speed every 5 minutes) is more scientific.

With the continuous improvement of labor costs, more and more enterprises have begun to pay attention to the field of industrial automation equipment, especially non-standard automation equipment, which is not as simple as the traditional standard equipment, but with flexible customization, easy operation and diversified functions to bring new development opportunities to the industrial manufacturing industry. China's non-standard automation equipment began to emerge, but encountered many obstacles in the development process. Non-standard automation equipment is in high demand In the past, China's manufacturing boom relied on a flood of cheap labor. However, with the change of time and environment, with the decrease of the new labor population in recent years, the improvement of people's living standards, labor is no longer a cheap resource, and it has become more and more common to find a job difficult, in order to meet the needs of production, automated production is gradually recognized and valued by business owners. Non-standard equipment as an important part of automated production in the past 10 years has become more and more popular, the market has also emerged a large number of non-standard equipment manufacturers. At present, the demand for enterprises to use automation equipment is increasing, due to the specific circumstances of each enterprise, the demand for non-standard automation accounts for a large proportion. The expenditure of non-standard equipment and machinery can be budgeted in advance, such as: machine depreciation, electricity, gas, daily maintenance, operator salaries, etc. The productivity of a machine can be equivalent to several (at least) to dozens or hundreds of people, of course, the faster the speed of the machine the higher the cost. The production cost of the product is saved to the maximum extent. Moreover, the quality of the products produced by the machine is more guaranteed. In China after the financial crisis, non-standard automation equipment is bound to be more prosperous. The non-standard automation market will grow rapidly, and the depth of application of automation products will continue to increase. In this field, compared with developed countries, there is a gap of 10-20 years at the domestic level. New non-standard automation equipment is often mechatronics equipment, making full use of the latest achievements in information technology. The designers of some Chinese enterprises are not familiar with electronic products, and dare not or will not choose them, which greatly limits the improvement of the level. However, in the past 10 years, non-standard automation has been widely used in Jiangsu, Zhejiang, Shanghai, the Pearl River Delta, Beijing and Tianjin, and domestic enterprises are catching up. Non-standard automation equipment development status Although the non-standard equipment industry as a whole shows an obvious upward trend, that is, the non-standard equipment market space is broad, and even some traditional industries will likely become the largest potential market. However, the number of non-standard enterprises in China is large, the scale is small, the technology is backward, and the competition is homogenized is also obvious defects, and there is at least a 10-20 year gap with developed countries in this field. New non-standard automation equipment is often mechatronics equipment, making full use of the latest achievements in information technology. The designers of some Chinese enterprises are not familiar with electronic products, dare not or will not choose, which greatly limits the improvement of the level, and many core technologies are not really independent, and the cost of relying on equipment imports is obviously difficult to reduce. At present, high-end products are still mainly imported from abroad. According to the market logic, the growing market space can improve the level of technology research and development of enterprises and expand the scale of enterprises, providing enterprises with good development opportunities. However, the objective situation is on the contrary, the domestic non-standard equipment enterprises have not come out of the vicious circle of low quality and low price, and are still simple imitation, and have not developed their own characteristic products, patented products, and have not accumulated more funds for the development of enterprises. At present, the small workshop production of a dozen people is still the mainstream form of non-standard equipment industry. Explore obstacles to development The formation of anything has its subjective and objective reasons, and the formation mechanism is intricate. The status quo of non-standard equipment is also the result of various elements. Although non-standard equipment is still a relatively healthy industry, the seven obstacles in front of it have increasingly affected the development of non-standard automation equipment industry. Non-standard equipment can not be mass-produced, large enterprises are not willing to do, and small-scale enterprises are easy to obtain living space. Non-standard equipment is no standard to rely on, according to the production status of the enterprise tailored equipment. The equipment of enterprise A can only be applied to enterprise A, and cannot be copied to enterprise B in mass production. Usually, it takes two or three months for a equipment of about 300,000 yuan to provide customer requirements, provide program design for non-standard equipment factories, discuss and determine the program, sign a contract, produce design drawings, process parts, and assemble and accept equipment. Because the input-output ratio is too low, large companies do not bother with small orders of such trivial and long periods. But such programs are attractive to small businesses with only a dozen people. A small business of sales and a few mechanical engineers and a few software engineers grew wildly. The size of the non-standard equipment market has increased, but the cake has grown, and there are more people who share the cake. In 2000, the domestic non-standard equipment is more well-known only in the Pearl River Delta and Yangtze River Delta some Taiwan factories, these factories add up to about 30. Query the relevant statistical data, the scale of non-standard equipment is estimated at about 600 million, and these 30 companies account for about 70% of the market share. By 2012, in China's hardware manufacturing town Chang 'an alone, there are more than 70 non-standard equipment factories, the country's small-scale non-standard equipment has been countless, orders of magnitude in more than ten thousand; The market size is also estimated to grow to about 60 billion. In a nutshell, although the market size has increased by 100 times, the manufacturers have increased by 1,000 times. The new market is occupied by many small manufacturers. Failed to form a scale enterprise. Non-standard equipment enterprise threshold is low, the quality of personnel is uneven. Why are there so many non-standard manufacturers in the market? The reason is that the initial investment cost of non-standard equipment plants is low, and the entire investment is estimated to be about 300,000. Several grinding machines, several milling machines, hundreds of flat houses, 10 or more people can operate a non-standard equipment business. Usually, the entrepreneurial model of non-standard equipment factory is two or three shareholders to invest together, a shareholder is responsible for sales, a shareholder is responsible for technology, and a shareholder is responsible for after-sales, and it does not need large capital and large enterprise intervention. This situation leads to the non-standard equipment industry is relatively closed, the industry can not be reshuffled, the good currency can not drive out the bad currency, and the good and bad enterprises are uneven. Pursue the doctrine, innovation research and development is less. Domestic non-standard enterprises rarely have new inventions, new creations, new applications. An important purpose for domestic enterprises to go to exhibitions and exhibitions at home and abroad is to discover new applications, new processes and new technologies. This approach is very positive in many ways. He has shortened the equipment gap between China and developed countries, improved the degree of industrial modernization and agricultural modernization, and thus reduced the labor intensity of the broad masses of people. However, there is no doubt that this kind of plagiarism under the banner of reference seriously reduces the enthusiasm of enterprises to develop new technologies and new applications; Over time, it has affected the technical ability of China's automation equipment industry, so that the core is always in the hands of European and American enterprises, and we rely on polluting the environment, selling physical strength, and demolishing houses to develop the economy, which is a very sad thing. In order to long-term development, we must attach great importance to the protection of intellectual property rights, so that enterprises can get long-term stable benefits from research and development, non-standard equipment industry in particular need to protect intellectual property rights. The requirements of enterprises for automation are still relatively primary, which restricts the development of non-standard automation industry to a higher level. Under the pressure of shortage of human resources, manufacturing enterprises choose automation. However, from the perspective of saving human resources, automation can be roughly divided into three stages: semi-automation, full automation, and the integration of automation and information. Based on cost considerations, many enterprises choose semi-automated equipment, slightly complex processes or manual completion, this semi-automated product a more understanding of mechatronics people can independently complete all the design. A large number of such low-level automation needs restrict the development of non-standard industries to higher levels. The industry is loose and does not form an organizational advantage. Non-standard equipment has not set up an industry association. As the saying goes, a crying child has milk to eat, without industry associations, it is difficult for the government to hear the voices from non-standard industries, and we will not get any preferential policies, at least in terms of tax. The manufacturers do not contact each other. The wariness between non-standard equipment enterprises is relatively strong, afraid of their technology being learned by others, afraid of their customers being stolen by others, and afraid of their backbone personnel being poached by others. This kind of non-contact and non-group cooperation has led to non-standard equipment increasingly falling into the mud pit of price competition. A non-standard enterprise should sell technology, is the solution, but now many non-standard enterprises are talking about material costs and management costs with customers. We should think that without technology, non-standard equipment is a pile of scrap metal, so we should explain more about how much our non-standard equipment can save customers costs, improve how much benefit, we take is a reasonable return of our mental labor. The advantages of scale enterprises are not obvious. Although small enterprises are the mainstream of the non-standard industry, there are also some medium-sized non-standard enterprises with more than 100 people. The annual output value of these medium-sized non-standard enterprises is in the tens of millions of levels, but due to management problems, designers and equipment personnel did not show enough responsibility, resulting in the product quality performance of some medium-sized non-standard enterprises is not satisfactory. Over time, many manufacturers have turned back to small non-standard enterprises to buy relatively cheap non-standard products. At present, the number of non-standard automation and mechanization enterprises in China is large, but the scale is small, and the technology is backward and the competition is homogenized. How to participate in the competition of this industry becomes a challenge! There is only chance when there is difficulty. In the face of good market prospects and development space, is also a particularly attractive place in this line, through the early survival of the enterprise, will usher in the rapid development of the industry

"Automation" is known as "sunrise industry" is the trend of today's scientific and technological development. At present, almost all industrial sectors can be hooked with automatic control, modern agriculture, national defense are also closely related to automation, and the application range of automation is quite extensive. The course content of automation majors intersects with electronic engineering, computer engineering, electrical engineering and even chemical engineering.

1, the structure of the structure of the equipment to a large extent affect the working middle temperature uniformity. Because the structure is difficult to be completely symmetrical, the uniform temperature from the face has an adverse effect. The door is in the front, the air conditioning room is at the back of the box, the upper supply air and the lower return air, and the forced convection. This kind of structure has good symmetry between left and right, and can easily achieve uniform temperature between left and right. 2, the sealing of the sealed box is not good, such as the door leakage, which affects the uniform temperature of the equipment studio. 3, the test volume is too large if the detection of temperature deviation requires that the test is placed in the work room, when the test volume is too large, or the way or location of the placement is inappropriate, the air convection is blocked, and it will also lead to a large temperature deviation. 4, the box wall heat conduction problem due to the heat conduction of the high and low temperature testing machine, and the heat loss of the high temperature box leakage or cold box leakage, in order to compensate for the heat loss, there will be a supply air temperature difference, the high temperature box supply air temperature is higher than the working temperature in the box, the low temperature box supply air temperature is lower than the working temperature in the box. Due to the inevitable supply air temperature difference, the temperature in the working room is not uniform.

1. Overview Some companies refrigeration system configuration, some accessories on the book must be fully matched. Is it really necessary to match all the accessories? Is it always good to have it all together? Anyway, nothing, just analyze it, share it with all friends, as to whether it is correct, it is a matter of opinion. 2. Oil separator The oil separator can backflow most of the compressor lubricating oil brought out from the compressor exhaust port, and a small part of the oil can be returned by the compressor suction port with the refrigerant through the circulation of the system. If the system oil return is not smooth, the oil will gradually collect in the system, which will still cause the heat transfer efficiency to decline, the compressor oil shortage and other faults. On the contrary, for refrigerants that are slightly soluble with oil, such as R404a, the over-oil separator will increase the saturation of the refrigerant dissolved oil. For large systems, because the system pipeline is thicker, the oil return is generally smooth, and the amount of oil is more, the oil distribution separator is more suitable, and for small systems, the smooth flow of the system's oil return is the key to the oil circuit, and the role of the oil separator is not large. 3. Liquid accumulator The liquid accumulator makes the uncondensed refrigerant in the refrigeration system not enter or enter the circulation system less, improving the heat transfer efficiency, but at the same time, it will bring about the problem of increasing the refrigerant charge and low condensing pressure. For small systems, the circulation flow is not large, and the purpose of liquid accumulation can be achieved through pipeline processing technology. 4, evaporation pressure regulating valve The evaporation pressure regulator is generally used in the dehumidification system to control the evaporation temperature so that the evaporator does not frost. However, in the unipolar circulation system, the use of evaporation pressure regulating valve must be connected to the refrigeration return air solenoid valve, which makes the pipeline structure complicated and is not conducive to the smooth system. At present, most test chambers are not equipped with evaporative pressure regulating valves. 5. Heat exchanger The heat exchanger has three advantages, one is that the condensed refrigerant can be supercooled, reducing the amount of advance gasification in the pipeline, the second is that the return refrigerant can be fully vaporized, reducing the risk of liquid shock, and the third is that the system efficiency can be improved. However, the access of the heat exchanger complicates the piping of the system, and the pipe loss will be increased if the pipeline layout is not focused on the process. Not conducive to small batch production company product configuration. 6. Check valve Since the system is used in multiple circulation branches, a check valve is installed at the air return port of the inactive circulation branch to prevent the accumulation of refrigerant back into the inactive circulation space. If the accumulation of gas in the pipeline does not affect the work of the system, it is necessary to consider preventing the accumulation of liquid. Therefore, not all sub-circuits need to be equipped with check valves. 7. Gas-liquid separator The gas-liquid separator is one of the effective means to avoid liquid shock and adjust the cooling capacity appropriately for the refrigeration system with variable operating conditions. However, the gas-liquid separator also cuts off the system's oil return, so the installation of the gas-liquid separator must install the oil separator. For the unit composed of Taikang fully enclosed compressor, because there is an appropriate buffer space in the air return port, it can play a certain role in gasification, so the gas-liquid separator can be omitted. For units with limited installation space, thermal bypass can be set up to vaporize excess return liquid. 8, cold PID control Cooling capacity PID control has a remarkable effect on energy saving in operation. Not only that, in the normal temperature (about 20℃) section where the temperature field index of thermal balance mode is relatively poor, the cooling capacity PID control system can achieve an ideal index. In terms of constant temperature and humidity can also reflect a good effect, so the cooling capacity PID control has been a more advanced technology for the test product refrigeration system. Cold PID control is divided into two kinds of time proportion and opening proportion, the time proportion is to control the refrigeration solenoid valve in a time period, the opening proportion is to control the flux of the electronic expansion valve. However, in the time proportional control, the life of the solenoid valve is a bottleneck, the best solenoid valve on the market is estimated, and the life is only 3 to 5 years, so it is necessary to calculate whether the maintenance cost is lower than the energy saving. The electronic expansion valve in the proportional control of opening is currently expensive, and it is inconvenient to purchase on the market, because it is also dynamic balance, and it also involves life problems

Sunlight is the guarantee for the survival of all living things on the earth, it brings light and warmth. However, excessive light and the steam generated by light can also cause harm, especially to the production of materials and products, and cause serious damage every year, causing an incalculable economic loss. The damage mainly includes fading, yellowing, discoloration, strength decrease, embrittlement, oxidation, brightness decrease, cracking, blurring and powdering. Products and materials that are directly exposed to sunlight are most at risk from the effects of light damage. In order for future products to adapt to and eventually resist the damage of sunlight and moisture, we use xenon lamp aging test chamber and ultraviolet aging test chamber. Xenon arc lamps that can simulate the full spectrum of sunlight are used in the xenon lamp aging test chamber to reproduce destructive light waves in different environments. The equipment can provide corresponding environmental simulation and accelerated testing for scientific research, product development and quality control. Xenon lamp aging test chambers can be used to select new materials, improve existing materials or evaluate changes in durability after changes in material composition. The equipment can well simulate the changes of materials exposed to sunlight in different environmental conditions. The equipment measures the light resistance of the material by exposing it to ultraviolet (UV), visible and infrared light. It uses filtered xenon arc lamps to produce an all-sunlight spectrum with maximum agreement with sunlight. Xenon arc lamps with proper filtration are the best way to test the sensitivity of products to longer wavelength ultraviolet and visible light in direct light or sunlight through glass. When you expose your product to direct sunlight outside, the amount of time it experiences maximum light intensity is a few hours a day. Even so, the worst exposure occurs only during the hottest weeks of summer. Xenon weathering test equipment can speed up your testing process, because it can be programmed to expose your product 24 hours a day to the equivalent of summer noon sunlight. The exposure experienced is significantly higher than outdoor exposure in terms of average light intensity and light hours/days. Thus, the test results can be obtained faster. Due to long-term exposure to fluorescent lamps, halogen lamps or other luminous lamps, products placed in retail locations, warehouses or other environments will also experience significant photodegradation. The Xenon lamp aging test chamber can also simulate and reproduce the destructive light generated in such commercial lighting environments, and can accelerate the test process at a higher intensity. The device uses a full-spectrum xenon arc lamp to simulate destructive light waves in sunlight, including UV, visible and infrared light. Depending on the desired effect, xenon lamp light is usually filtered to produce a suitable spectrum, such as direct sunlight, sunlight through a glass window, or UV spectrum. Each filter produces a different distribution of light energy. Light irradiance is the ratio of light energy irradiated on a flat surface. The equipment must be able to control the intensity of light irradiation to achieve the purpose of accelerating the test and reproducing the test results. Changes in light irradiance affect the rate at which the material deteriorates, while changes in the wavelength of the light wave, such as the energy distribution of the spectrum, affect both the rate and type of material degradation. The device is irradiated with a light-sensing probe, or solar eye, a high-precision light-control system that compensates for any loss of light energy caused by aging or any other change in the lamp. The solar eye allows the appropriate light irradiance to be selected during the test, up to the equivalent of midday summer sunlight. The solar eye can continuously monitor the light irradiance in the irradiation chamber, and can accurately maintain the irradiance at the working set value by adjusting the power of the lamp. Due to the long working time, when the irradiance drops below the set value, a new lamp needs to be replaced to ensure the normal irradiance. The service life of the lamp depends on the irradiance level used, and the general life of the lamp is 1000 hours. Light tube replacement is convenient and quick. Long-acting filters provide assurance that the required spectrum is maintained. In addition to conducting photodegradation tests, xenon lamp aging test chambers can also simulate the damaging effects of outdoor moisture on materials by adding moisture and water spray options. Moisture is also the main factor causing damage to some materials, and the higher the content of moisture, the more it will accelerate the destruction of materials. Humidity can affect the degradation of indoor and outdoor products, such as various textiles. This is because when the material tries to maintain a moisture balance with the surrounding environment, the physical stress on the material itself increases. Therefore, when the humidity range in the atmosphere is larger, the overall stress of the material is greater. The negative effect of humidity on the weatherability and colorfastness of materials has been widely recognized. The moisture function of this device can simulate the effect of indoor and outdoor moisture on the material. The device provides relative humidity control, which is important for many humidity-sensitive materials and is required by many test protocols. The use of water spray function greatly expands the climatic conditions that the equipment can simulate. Due to frequent erosion from rain, the coating layer of wood, including paints and colorants, will appear corresponding erosion phenomenon. This rain-washed action washes away the anti-degradation coating layer on the surface of the material, thereby exposing the material itself directly to the damaging effects of UV and moisture. The rain spray function of this equipment can reproduce such environmental conditions to enhance the relevance of climatic aging tests for certain coatings. The spray cycle is fully programmed and can be performed with or without a light cycle. In addition to simulating material degradation caused by moisture, it can also effectively simulate temperature changes and rain erosion processes. Outer coatings on roofs, car parts, and metal buildings or structures can experience sudden temperature changes. For example, a hot summer causes the heat inside the material to build up, and a sudden shower will cause the heat to dissipate quickly. This dramatic temperature change impact is a challenge and test for many materials. The effect of this environmental condition on the material can be reproduced through the water spraying function of the device. Infrared light emitted from the tubes reconstructs the heat build-up process, while cold water spraying produces a dramatic temperature change. The temperature is not controlled during the rain spray cycle. The water quality of the water spraying circulation system is deionized water (the solid content is less than 20ppm), with the water level display of the storage tank, and two nozzles are installed on the top of the studio, the water is recyclable, and the spray pressure is adjustable between 0.12 and 0.15Mpa. Equipment heating system adopts far-infrared nickel-chromium alloy high-speed heating electric heater; High temperature, humidity, light completely independent system (do not interfere with each other); The output power of temperature control is calculated by microcomputer to achieve high precision and high efficiency. Equipment humidification system adopts external boiler steam humidifier, with automatic water level compensation, water shortage alarm system, far infrared stainless steel high-speed heating tube, humidity control adopts P.I.D + S.S.R, the system coordinated control with the channel.

Operation method and precautions: 1. Determine the power supply and connect the power cable. (Pay attention to the difference between the power supply of the machine, the external incoming power supply of 220V and 380V) 2. The table connecting cable is connected to the corresponding output outlet. (Vertical output or horizontal output, and pay attention to the three-axis switch direction selection) 3. Before starting, fine-tune the amplitude modulation adjustment to "0" position. 4. Press the power switch to ON, that is, turn on the power supply, and the indicator is on. (except 5000Hz) 5. When L type AM output, slowly rotate the amplitude to adjust the twist, so that the table reaches the required amplitude. 6. When the function is output, the amplitude of the output frequency is mainly through the function regulator. At this time, the fine-tuning amplitude-modulation adjustment twist only plays the role of micromotion adjustment. 7, adjust the amplitude should be careful not to exceed the amplitude range of the machine itself, otherwise there will be out of control or abnormal sound, should immediately stop working to correct. 8. After normal operation or regular time operation, the main measured object on the table should be fixed to prevent the loss of the object caused by vibration displacement. 9. The table can not work in the overload or no-load large amplitude state. 10. The control box is a power control component and must not withstand heavy objects and violent vibration. 11. Do not unplug any cable during work. 12. The control box and countertop have heat dissipation holes, and any logistics and debris are not allowed inside. 13. If the noise is found, stop the machine immediately for inspection, or contact the manufacturer to deal with it before continuing operation. Functions and characteristics: First, the role of vibration test bench: 1, early screening of defective parts. 2. Strength of structure. 3. Loosening of the bond. 4. Damage of parts. 5, protect the wear of materials. 6, circuit short circuit and intermittent instability. 7, the standard value of each part offset. 8. Poor contact of electronic components. 9, find the resonance relationship between parts, structure, packaging and transportation process. Two, the advantages of vibration test bench: 1, design, can analyze the damage point, easy to bad points. 2, quality, can analyze the differences and bad points generated by each batch of products. 3, during production, it can be completely measured while vibrating, so that the product defect rate is found early. 4, durability measurement, make the product durable use, make the non-durable components improved early, the company's brand reputation will be better.

Environmental testing, a type of reliability testing, has evolved into a method of predicting how the environment in which a product is used affects the performance and functionality of the product. In other words, environmental tests are used to assess the degree of environmental impact on the product before it is put on the market; When the function of a product is affected, environmental testing is used to identify the cause and measures are taken to protect the product from environmental impacts to maintain product reliability. These tests have gone far beyond their original purpose and are now used in a wide range of applications, including the development of materials and products, various inspections during the production process, inspection before transportation and quality control after transportation, as well as to analyze defects during actual use of products and to improve new products. Environmental testing is very effective for testing methods and maintaining product reliability. The environmental test we talk about here is a narrow sense, and actually refers to the environmental test that is artificially simulated (hereinafter referred to as environmental test). In a broad sense, environmental tests are basically divided into three categories: "natural exposure test", "artificial simulation test" and "field operation test". Natural exposure test is to test samples exposed to natural environmental conditions for a long time. Field operation test is to test the sample device in a variety of typical use sites and make it in normal operation. These two tests can directly reflect the performance and reliability of the product in actual use, and are also the basis for verifying the accuracy of the manual simulation test. However, the test cycle is long, the cost of manpower and material resources is large, and the former test conditions can not be controlled, affecting the reproducibility of the test, and sometimes can not keep up with the development of products; The latter data feedback is slow. Therefore, in order to identify the adaptability of products to the environment in a relatively short period of time, artificial simulated environmental tests are used in scientific research and production work, that is, the role of one or more environmental factors is simulated in the laboratory test equipment (box or room), and it is appropriately strengthened. The determination of the test conditions of the artificial simulation test requires that it can not only simulate the authenticity of the main factors in the environment, but also play a certain acceleration role in time, but the degree of acceleration should not change the law of the actual damage mechanism of the product. Therefore, the test conditions and methods of artificial simulation test must be organically linked with the grade and value of product environmental conditions. As shown in Figure 1, the environmental test can be simply divided into "climatic environmental test", "mechanical environmental test" and "comprehensive environmental test". Climate-related environmental tests include environmental stress tests such as temperature, humidity and pressure, while mechanical environmental tests include environmental stress tests such as shock and vibration, and comprehensive environmental tests are stress tests that combine environmental factors such as climate and machinery. Environmental test Mechanical environment test Comprehensive environmental test Climatic environment test Ambient stress: shock, vibration, collision, acceleration, high noise, high wind Environmental stress: the combination of mechanical environment and climatic environment environmental factors Ambient stress: temperature and humidity, gas, salt spray, wind and rain, pressure, solar radiation Of course, the use of environmental testing equipment to conduct tests can not be completely accurate to reproduce the use of the product environment and simulate all environmental factors, it is important to understand the limitations of environmental testing. An environmental test consisting of a single factor (temperature, humidity, pressure, vibration, shock, or a substance such as salt) is called a simple environmental test. In practice, it is difficult to produce a completely single environment, and most test environments are very complex. Therefore, when designing the test conditions, the test personnel need to choose the most important environmental factors that have the greatest impact on the product, so the environmental test can only be a man-made environment that is very different from the real environment. In general, product defects are caused by the following aspects: a. The concentration and diversity of raw materials, friction, wear, stress, heat, current and electric field strength, which can affect the performance of certain aspects of the product; b. Factors arising from product characteristics (raw materials, manufacturing processes, structural components, and mass production) during product design and manufacturing; c. Stress caused by the external environment. Therefore, the test conditions must be based on the specific product conditions, for different products are not the same. If the product being tested has changed, the corresponding environmental test should also be changed. 2. Temperature stress Environmental stress conditions can cause product failure, and Hughes Aviation (USA) technical data clearly shows the relationship between failure and environmental stress (see Figure 2). It can be seen that the ground failure caused by temperature and humidity environmental stress accounts for about 60% of all environmental stress-induced failures, and there is a close relationship between temperature stress and failure. At present, all over the world, no matter from the land to the sea or from the high altitude to the space, electronics and other fields of products are widely used. Because the temperature decreases with the increase of height or at high latitudes in winter, or some products are located close to refrigeration components, equipment or systems, or some products themselves include refrigeration components, equipment or systems, resulting in a low temperature environment. Low temperature will have different degrees of harmful effects on almost all materials, the physical properties, electrical properties of various materials that constitute the product will change, resulting in temporary or permanent performance decline, and even cause failure. Similarly, the natural high temperature in the low-latitude tropical areas, the warming of solar radiation, the temperature rise caused by poor ventilation and the temperature rise caused by the heat dissipation sample in use, the high temperature will reduce the reliability of the electronic combination, and the sealing parts, rubber parts and plastic parts of the mechanical structure will be rapidly aging and deteriorating by high temperature and solar radiation. The structure, physical properties and electrical properties of various other materials will also change greatly, resulting in temporary or permanent damage and performance changes. In addition, in the process of product storage, transportation, use and installation, in addition to the change of natural climate, it will also encounter changes in environmental temperature induced by human social practice. For example, the equipment is moved from the high temperature indoors to the relatively low temperature outdoors; Or move from outdoors where the temperature is relatively low to indoors where the temperature is higher; Or the equipment used outdoors is suddenly rained or soaked in cold water after intense solar radiation; Or the extreme rise in temperature leads to solder reflux phenomenon, or the temperature of the surrounding devices increases rapidly when the motor is started, and the temperature of the surrounding devices will plummet when the motor is turned off. Or the device may be connected to the power supply in a low-temperature environment, resulting in a steep temperature gradient inside the device. Cutting off the power supply in a low-temperature environment may result in a steep temperature gradient in the opposite direction. Or when the aircraft takes off or lands, the external equipment of the aircraft may have a sharp change in temperature and so on. Because the rapid temperature change will make the product subject to a certain thermal impact force, under the action of this thermal impact force, it will lead to the coating layer of electronic and electrical components falling off, the sealing material cracking or even breaking, the filling material leaking, etc., which will cause the electrical performance of electronic components to decline; For products composed of different materials, due to the uneven heating of the product when the temperature changes, the product deformation, cracking, crushing and so on. Due to the large temperature difference caused by the temperature change, the surface of the product will condense or frost at low temperature, and evaporate or melt at high temperature. The result of such high and low temperature repeated action leads to and accelerates the corrosion of the product. The following table shows the main types of temperature stress induced failures. Table 2 Main types of failure caused by temperature stress Failure environment stress condition sensitive elements and materials Classification (cause) failure mode in large classification Temperature high temperature aging aging tensile strength aging Insulation aging temperature + time plastic, resin Chemical changes in thermal decomposition temperature of plastics, resins Soften, melt, vaporize, sublimate and twist temperature metal, plastic, hot fuse High temperature oxidation oxidation layer structure temperature + time connection point material Thermal diffusion (metal compound structure) lead break temperature + time different metal connection site Intermediate damage semiconductor hot spot temperature, voltage, electron energy heterogeneous materials Heat accumulation combustion (residual heat combustion) Combustion heating + drying + time Plastics (e.g. wood chips with Vinylon and polyurethane paint) Puncture the internal short circuit Poor insulation high temperature (200~400℃) silver, gold, steel, magnesium, nickel, lead, palladium, platinum, tantalum, titanium, tungsten, aluminum Non-intrinsic short circuit Poor insulation high temperature (400~1000℃) halides of copper, silver, iron, nickel, cobalt, manganese, gold, platinum and palladium Migration electromigration disconnect, lead break temperature (0.5Tm) + current (density 106A/cm2) e.g. Tungsten, copper, aluminum (especially aluminum leads in integrated circuits) Spread metal fatigue, damage temperature + stress + time springs, structural elements Plastic fatigue, damage temperature + stress + time springs, structural elements Low-temperature brittle metals damage low-temperature body-centered cubic crystals (e.g., copper, molybdenum, tungsten) and close-packed cubic crystals (e.g., zinc, titanium, magnesium) and their alloys Plastic damage Low temperature + low humidity high glass transition temperature (e.g. cellulose ethylene ammonia), low elasticity of amorphous (e.g. styrene, methyl acrylate) Flux flow Flux flow sticking to cold metal surfaces noise, low temperature connections, especially to components connected to printed circuit boards (e.g. switches, connecting devices) Therefore, when discussing the product life related to temperature, the expression of "θ℃ rule" is generally used. Specific applications can be expressed as the "10℃ rule", such as 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 temperature affects product life (failure). On the contrary, one can accelerate the failure of the product in a short period of time by increasing the ambient temperature or reducing the ambient temperature or using the alternations of ultra-high and ultra-low temperatures to determine the characteristics of the product and the fault problems caused by the different thermal expansion coefficients of the dissimilar materials that make up the components. It is widely used in development screening test, material characteristic test, limit test, evaluation test, quality confirmation test, accelerated life aging test and other occasions. 3. Temperature test equipment Temperature test equipment is generally composed of studio, regulating equipment, auxiliary equipment and control system. The regulating system includes heater, evaporator and air supply device, auxiliary equipment main room refrigeration unit, control system includes temperature controller, program setter, safety alarm device and so on. The heater uses the electric heating method of resistance wire or electric heat pipe; In addition to natural heating for the drying chamber of the non-cooling sample high temperature test, it is generally equipped with a air supply device for forced air circulation, and the air supply method is often sent from the upper side to the lower side or the whole face plate top to the lower side, which is very important for the uniform performance of the entire test equipment. The refrigeration method is mostly used for mechanical refrigeration, the refrigerator has a semi-closed or fully closed form, the cooling circuit also has a water-cooled form or an air-cooled form, the refrigerant is now mostly environmentally friendly refrigerant, the throttling method uses capillary or electronic expansion valve, which can improve the accuracy and the life of the circuit, and can work continuously for a long time. The control system now generally adopts PID mode, so that the heating power is automatically adjusted and controlled with the deviation of the actual temperature of the equipment and the set temperature, so as to achieve stepless adjustment and small temperature fluctuation; The display part has also been upgraded from the previous digital display mode to the LCD touch screen mode, such as the Pmeter installation of ESPEC Group is the use of 6.54-inch TFT color LCD display screen, clear and beautiful, more easy to operate. In addition, the insulation layer of the equipment adopts glass wool or polyurethane foam layer, which has small thermal conductivity and good temperature resistance. Temperature detection using thermocouple, platinum resistor and thermistor, etc., high precision. The temperature test needs to be considered thoroughly, so it is also crucial to consider the selection of appropriate test equipment. 1. The test range must be required to meet the product failure possibility test range, that is, whether it is a high temperature box or a low temperature box or a hot and cold shock box should be able to meet the extreme temperature conditions specified in the test requirements. 2. The test equipment must be selected in order to ensure that the volume of the test sample should not be greater than 1/5 of the working volume of the test equipment. 3. In order to ensure the uniformity of temperature in the test area, choose whether to use forced air circulation or no forced air circulation according to the heat dissipation of the sample. For example, the LG type drying box produced by Shanghai ESPEC uses hot air natural convection mode, which is especially suitable for powder drying, while the LC type drying box uses hot air forced circulation mode. The difference in the temperature distribution of the equipment will have a greater impact on the test results. When a larger sample is used, or the number of samples tested at the same time is large, the test results will vary greatly with different locations, so the equipment with the best temperature uniformity should be selected. For example, the Z series temperature control box produced by Shanghai ESPEC has a uniformity of 2.0 ° C. 4. Sample temperature can be measured in two ways: upwind and downwind sensor. The position and control method of the temperature control sensor of the equipment can be selected, and the appropriate equipment should be selected according to the test requirements. 5. To prevent the sample heat absorption or heat release caused by heat radiation or heat conduction in the test area, the heating or cooling system device of the equipment is required to have no effect on the sample. 6. Easy to record and display, the cycle test requires the installation of automatic counters, indicators, recording equipment and automatic closing instruments. 7. Easy sample placement can require a sample rack for placement or hanging, and the sample rack will not change its mechanical properties due to high and low temperature changes. 8. There should be a lead hole to introduce the test power supply into the equipment chamber. 9. There should be protective measures for both the damage of the sample and the safety of the test personnel. For example, there are observation Windows and lighting, and alarm devices such as power supply interruption, water shortage, overtemperature protection, and operator protection. 10. Whether remote monitoring function is required. Precautions when using temperature test equipment: 1. When conducting bulk sample test, there will be temperature and humidity deviation between the updraft and downdraft, so the sample location should be carefully considered. Try to place in the center of the working space of the test equipment, the samples shall not contact and overlap each other, and a certain interval should be left to allow air circulation; It should also be ensured that the sample is easy to move during the test and easy to replace the sample during the test. 2. Check whether there are volatile substances such as oil and gas in the test area, check whether there are odor substances, and the test consequences of such substances must be confirmed in advance. 3. Pay attention to confirm the temperature of the test sample in the test area. 4. In order to keep the temperature in the temperature zone consistent, it is necessary to ensure the minimum fluctuation of the test environment temperature and equipment power supply as far as possible, to ensure that the test sample does not produce thermal radiation and does not absorb heat to ensure the stable temperature of the test zone. 5. After the temperature test equipment completes the test, the rapid removal of the test sample will cause unnecessary stress on the sample and may obtain unexpected results. Therefore, the sample must be removed after the test sample has cooled to the ambient temperature.

Transportation equipment industry Furniture, food, electronics, metallurgy, electricity, coal, chemical, building materials, wharf and other industries. Shenzhen production line for conveying powder material vacuum conveying device, easy to install, easy to clean, low noise, no dust conveying advantages. Meet the requirements of pharmaceutical, food and other industries. Working principle of vacuum conveying equipment Compressed air, multistage jet vacuum pump (a) driven vacuum. End the discharge valve (b) near, then store the hopper (c) and (d) in the vacuum producing tube. Under vacuum conditions, the material is sucked into the powder storage tank through the suction (5) pipe. Filter (F) to achieve a good separation of our gas and powder. Although compressed air delivers powder, tamped recoil bag (G) When the vacuum pump stops running, the valve at the end of the feed is open and the material is lowered to the feed position. At the same time, the recoil of the compressed air released in the balloon automatically cleans the powder particles adhering to the filter. The vacuum pump works and begins a new cycle. A controller for conveying, material and time throughout the process, controlled by pneumatic or electric (high). Introduces the classification and classification of transportation equipment The conveying device refers to the continuous conveying of materials in the material conveying machinery, assembly line, and production line is also known as the target line. The transmission line can be horizontal, inclined and vertical transmission, may form a space, the transmission line, the transmission line is generally fixed. Automated conveying equipment, long distance, and can be completed in the process of transmission, while some processing business transmission capacity, so the application is very wide. Chain line: towing chain plate clamp workpiece plane ship movement, to achieve the purpose of production. Line adopts modular assembly model, working position can be set according to process requirements. Station equipped with power outlets, toolbox, trash can, put the whole process to express, orderly. Plug-in in the assembly line: the use of chain drag tool car, leveling operation, workpiece assembly.

1 A brief discussion on the use and maintenance of environmental and reliability test equipment [Abstract] : This paper describes the current status of environmental test equipment, the correct use of environmental test equipment and the general maintenance of environmental test equipment. The purpose is to help the majority of environmental test personnel to have a preliminary understanding of the correct use of environmental test equipment. [Key words] : environmental test equipment use maintenance Environmental test equipment is a combination of test equipment that simulates one or more harsh environments by artificial methods in the laboratory, and is an environmental test equipment for the development and development of new products and the inspection of product quality performance. It is our indispensable inspection and test equipment. Therefore, the correct use and maintenance of environmental and reliability test equipment is particularly important. According to the environmental factors simulated by the test equipment, the environmental test equipment can be roughly divided into: climate environmental equipment (including biological environmental test equipment), mechanical environmental test equipment, climate mechanical comprehensive environmental test equipment and other environmental test equipment. We have dozens of sets of various environmental test equipment. The environmental test equipment provides the necessary information and data for the development of modern high-tech products and the regular inspection and acceptance test of products. one Current situation of environmental test equipment At present, most of the domestic environmental test equipment is produced in order to meet the national standard GB2423 "Basic test Procedures for electrical and electronic products", these environmental test equipment now has the corresponding product national standard, Such as GB10586-89 "wet heat test box technical conditions" GB10589-89 "Low temperature test box technical conditions" GB10591-89 "high/low temperature test box technical conditions" GB10591-89 "high/low temperature test box technical conditions" and so on. Before the 1980s, most of the environmental test equipment used in China was introduced from Western countries, and the price is relatively expensive, and now, with the development of electronic technology, especially the development of control technology, from analog control to the current digital control; Display mode from pointer to digital and then to the present touch screen display; The control accuracy is improved from ±1℃ to 0.1℃ or even within 0.01℃. Equipment volume from very small box, to hundreds of cubic large room (room), China's environmental test equipment manufacturers have been able to produce equipment that meets the test requirements. The performance can be comparable to imported equipment, and the price is only about half of imported equipment. However, some special equipment, such as temperature shock equipment, rapid temperature change (15℃/min) can not be localized or produced equipment can not meet the requirements. 2 two The correct use of environmental test equipment In spite of this, environmental test equipment is still a kind of precision and valuable equipment. The correct use and operation of environmental test equipment can not only provide accurate basis for testing personnel, but also make the normal operation of environmental test equipment for a long time and extend the service life of the equipment. First of all, when doing environmental tests, it is necessary to be familiar with the sample performance, test conditions, test procedures and test technology required for the test, to be familiar with the technical performance of the test equipment used, to have an understanding of the structure of the equipment, especially the operation and performance of the controller. Also carefully read the operation manual of the test equipment, so as to avoid the abnormal operation of the test equipment caused by operational errors, resulting in damage to the test sample and incorrect test data. Secondly, reasonable selection of test equipment. In order to ensure the normal conduct of the test, the appropriate test equipment should be selected according to the different conditions of the test sample, and a reasonable proportion should be maintained between the effective volume of the test sample and the test chamber. For the test of the heating test sample, its volume should not be greater than one-tenth of the effective volume of the test chamber. For non-heating test samples, the volume should not be greater than one-fifth of the effective volume of the test chamber. For example, a 21 'color TV in the temperature storage test, choose a cubic volume of the test box can meet the requirements, and in the power work, it can not meet the requirements, should be changed to a larger test box, because the TV at work to radiate heat. Third, place the test sample correctly. The location of the test sample should be more than 10cm away from the box wall, and multiple samples should be placed on the same plane as far as possible. Fourth, for the environmental test required to add media in the test, it should be correctly added according to the test requirements. If the water used in the damp heat test chamber is required, the resistivity of the water used in the test chamber shall not be less than 500 euros. Meters, general tap water resistivity of 10--100 euros. Meters, distilled water resistivity 100- 10000 euros. M, deionized water resistivity 10,000-100,000 ohms. Therefore, the wet heat test water to use distilled water or deionized water, and must use fresh, because water and air contact, vulnerable to carbon dioxide and dust pollution, water has the nature of soluble substances, after a long time, the resistivity to decline. Now there is a pure water on the market is more economical, and convenient, its resistivity is equivalent to distilled water. Fifth. Use of damp heat test chambers. The wet bulb gauze (wet bulb paper) used in the wet heat test chamber has certain requirements, not any gauze can be used instead, because the relative humidity reading is the difference between the root distance and the temperature and humidity, strictly speaking, it is also related to the atmospheric pressure and wind speed of the local time. The value of wet-bulb temperature is related to the amount of water inhaled by the gauze and the situation of surface evaporation. These are directly related to the quality of gauze, so the weather stipulates that wet gauze must be a special "wet gauze" woven from linen. Otherwise, it is difficult to ensure the correctness of the value of the wet bulb thermometer, that is, the correct humidity. In addition, the placement of wet gauze is also clearly specified, the length of gauze is 100mm, the sensor probe is tightly wrapped, the probe is 25-30mm from the humidity cup, and the gauze is immersed in the water cup, so as to ensure the correctness of equipment control and humidity. Three. Maintenance of environmental test equipment There are many varieties of environmental test equipment, but the most widely used environmental test equipment is high temperature, low temperature, wet and heat test box, and today's more popular is a collection of high temperature, low temperature, wet and heat as one of the test box - high and low temperature wet and heat test box, which is more difficult to repair than other environmental test equipment, and representative. The following high and low temperature wet heat test chamber as an example, talk about the structure of high and low temperature wet heat test chamber and some common faults and troubleshooting methods. (1) The structure of the common high and low temperature wet and heat test chamber In addition to correct operation according to the operating procedures, the test personnel should also have an understanding of its structure. The high and low temperature wet heat test chamber is composed of box, air circulation system, refrigeration system, heating system and humidity control system. The air circulation system generally adopts the structure of adjustable air supply direction. There are two kinds of humidification system: boiler humidification and surface evaporation; The cooling and dehumidifying system adopts the refrigeration structure under the condition of air conditioning. The heating system adopts two structures: electric fin heating and electric furnace wire direct heating. Humidity and humidity test method adopts wet and dry bulb test method, and also uses humidity sensor direct measurement method; The control and display operation interface uses separate and independent temperature and humidity controllers or combined temperature and humidity controllers. (2) Some common faults and elimination methods of high and low temperature humid heat test chamber: 1. In the high temperature test, if the temperature change does not reach the test temperature value, you can check the electrical system and eliminate the fault one by one. If the temperature rises very slowly, it is necessary to check the wind circulation system to see whether the regulating baffle of the wind circulation is open normally, and on the contrary, check whether the motor of the wind circulation is running normally. If the temperature overshoot is severe then You need to set the PID parameters. If the temperature rises directly and the temperature is too high, then the controller fails and the control instrument must be replaced. 2. If the low temperature does not reach the test index, then you should observe the temperature change, whether the temperature drops slowly or the temperature tends to rise after the temperature reaches a certain value. The former should check whether the studio is dried before the low temperature test, and the test samples are put into the studio after the studio is kept dry. So that the wind in the work room can not be fully circulated, after eliminating the above reasons, it is necessary to consider whether it is the fault in the refrigeration system, so it is necessary to ask the professional personnel of the manufacturer to carry out maintenance. The latter phenomenon is caused by the use of the equipment environment is not good, the ambient temperature of the equipment is placed, the position of the placement (the distance between the box and the wall) should meet the requirements (are specified in the instructions for the operation of the equipment). 3. In the wet heat test, the actual humidity will reach 100% or the actual humidity is very different from the target humidity, and the value is much lower, the former phenomenon: it may be caused by the dry gauze on the wet bulb sensor, it is necessary to check whether the water is short of water in the sink of the wet bulb sensor, and the water level in the sink is automatically controlled by a water level controller Check whether the water supply system of the water level controller is normal and whether the water level controller works normally. Another possibility is that the wet gauze due to the long use time, or the purity of water supply quality, will make the gauze hardened, so that the gauze can not absorb water and dry, as long as the replacement or cleaning of the gauze can eliminate the above phenomenon. The latter phenomenon is mainly that the humidifier system does not work, check the water supply system of the humidifier system, whether there is a certain amount of water in the water supply system, whether the water level control of the humidifier boiler water level is normal, and whether the water level in the humidifier boiler is normal. If all the above is normal, it is necessary to check the electrical control system, which should be repaired by professional maintenance personnel. 4. When the equipment suddenly fails during the test operation, the corresponding fault display prompt and sound alarm prompt will appear on the control instrument. The operator can quickly check which type of fault belongs to the troubleshooting chapter in the operation and use of the equipment, and then ask the professional to quickly troubleshoot the fault to ensure the normal conduct of the test. Other environmental test equipment in the use of other phenomena, it is necessary to specific phenomena, specific analysis and exclusion. The environmental test equipment should also be regularly maintained, the condenser of the refrigeration system is regularly cleaned, the moving parts should be lubricated according to the instructions, the electrical control system is regularly maintained and inspected, and so on.

Growing Demand for Environmental Test Chambers:The demand for environmental test chambers is on the rise, driven by the need to simulate various environmental conditions for product testing. These chambers are used to test the performance and durability of products under extreme conditions such as temperature, humidity, vibration, and altitude. With industries focusing on improving product quality and reliability, the market for environmental test chambers is experiencing significant growth.