This paper mainly introduces how to prevent the system problems caused by elbow mismatch, leakage and multi-matching in the welding process of air conditioner heat exchanger during the welding process of elbow joint. Through comparing the difference between the traditional way and the on-line monitoring through the statistical data in the production process, the application of visual on-line monitoring in the production of air conditioning heat exchanger is promoted.

In the design of any electrotechnical product,the hazards of abnormal heat need to be considered. The results of ball pressure test is one of the basis for the selection of non-metallic materials In the process of the entire product testing certification; and it is chosen as proficiency testing projects in domestic and foreign laboratories which shows the importance of the ball pressure test ability. The testing process of ball pressure is complicated and there are many factors influencing the results of ball pressure test; this paper analyzed using devices and operation methods in the process of ball pressure test according to new standard GB/T 5169.21-2017 and IEC 60695-10-2:2014.

In this paper, based on the working conditions of the light commercial reciprocating compressor and the effect of the frozen oil in the reciprocating compressor, the viscosity of the commercial reciprocating compressor is compared and analyzed by using the viscosity tester of the Cambridge VISCOpro2000 oil product, and the commercial reciprocating refrigeration compression is made for the commercial reciprocating compressor. Provide data support and accumulation for compressor reliability evaluation and oil selection direction.

Foot massaging is a traditional health manner in China and foot massager makes this manner more convenient. However, there are some problems such as microbial growth and cross-infection due to the warm water, mixed use and so on. Many foot massagers with ozone generator appear in the market now and promote the ability to cure athletes. The theory of cure athletes is to eliminating the microbiology that causing athlete's foot. This paper study the eliminating microbiology performance by adding E.coli, S.aureus, C.albicans and T.rubrum into Foot massager. The results show the highest eliminating rate are 50.00% for bacteria and 62.00% for fungi in the test duration of 30min. Even if the test duration extend to 60min, the highest eliminating rate are only 50.00% for bacteria and 62.00% for fungi. This shows practical effect of eliminating microbiology is false promotion. In order to put an end to such problems and promote the industry development, standards about the eliminating microbiology performance should be drafted and strengthen market supervision at the same time.

According to the American Standard ANSI/AHRI 1230-2010 《Variable Refrigerant Flow Rate (VRF) Multi-connected Air Conditioning and Heat Pump Equipment Performance Evaluation a set of 48HP multi-line integrated test benches was designed and constructed with a certain equipment manufacturer. The test methods of wind tunnel air enthalpy difference method and liquid refrigerant method are mainly adopted, and the test requirements for multi-connection of air source and water source heat pump are met at the same time. In addition to satisfying the technical requirements of environment temperature and humidity measurement and control, temperature field, air leakage rate and other technical requirements of VRF multi-line through experiments, and the average energy-saving is over 20% more than conventional control means, because of the effective energy-saving control method.

When conducting the electrical strength test of Chapters 13.3 and 16.3 of IEC 60335-1, the short-circuit and release energy requirements for the high-voltage power supply capacity of the equipment when the test voltage is≥4000V, the short-circuit current I_s≥200mA, trip current I_r≥100mA. In the JJG 795 verification procedure, only I_r is verified, and I_s is not verified, so the laboratory needs to master a method of verifying I_s. This article understands I_r and I_sfrom the working principle of the high voltage tester, and then introduces the methods of indirect verification and direct measurement of I_s.

Discussion on the test method of Coverage percentage test, Dust removal from hard flat floors test, Dust removal from corner test in QB/T 4833-2015 <Household and similar cleaning robot>. Point out the problem and put forward suggestions for improvement.

Environmental humidity in the air-enthalpy test method has a great influence on the measurement of air conditioner capacity, so it is very important to ensure the accuracy and reliability of environmental humidity. There are many factors that affect the humidity of the environment. There are many factors affecting environmental humidity, and the wind speed of the sampler is one of them. In order to keep a better consistency between laboratories, this paper puts forward better suggestions on the limit range of the wind speed of the sampler through theoretical analysis and experimental verification.

According to the requirements of GB 26920.2-2015 "Energy efficiency limits and energy efficiency grades for commercial refrigerators Part 2: commercial refrigerators for self-contained condensing units", this paper summarizes the problems that should be paid attention to in the process of energy conservation certification testing work for commercial refrigerated cabinets with self-contained condensing unit (hereinafter referred to as "commercial refrigerated cabinets with self-contained condensing Unit "), and puts forward its own opinions on the problems encountered by summarizing the daily practical testing work, in combination with its own understanding of standards and certification rules.

In the air purifier standard GB/T 18801-2015, the test range of formaldehyde CADR in the 30 cubic meter test chamber is 20~400m³/h. Now in the market there is a large part of the air purifier whose test range of formaldehyde CADR is greater than 400m³/h. Also, the photometric spectroscopy using phenol reagent must be carried out by 4-port cross-sampling method, which is cumbersome and requires high professional level for the experimenter. The online mass spectrometry detection method can avoid the cumbersome sampling method. Moveover, such method can collect more data points at the same time. The measurement range is wider, and the results are more realistic and reliable. In this paper, phenol reagent spectrophotometry and on-line mass spectrometry, respectively, were used to test the air purifier with formaldehyde CADR greater than 400m³/h. The test results were analyzed to compare the differences between the two methods..

This paper mainly focuses on Renesas' 3D gesture recognition technology based on capacitive touch detection, including the principles of 3D coordinate calculation, the algorithm of X/Y/Z triaxial coordinate calculation and the noise immunity technology. Based on the 3D coordinate calculation, renesas 3D gesture recognition solutions are also introduced.

The performance of indoor unit of air conditioner is the comprehensive influence result of multiple design parameters. This paper selects multiple parameters that affect the performance of the indoor unit of the air conditioner, and using orthogonal analysis for experimental design. After designing multiple parameters levels, the orthogonal table obtained from the experimental design was used to determine the experimental protocol and to conduct experimental tests. Finally, by analyzing the influence of each parameter and the interaction between each parameter to the performance of the indoor unit of air conditioner, the influence of each parameter and the interaction to the air conditioner is obtained, as well as the optimal combination of parameters.

Starting from the definition of live parts,this paper analyzes the definition of live parts, and how to judge whether a component is a charged part or not when the item protection against access to live parts is tested, summarizes the test procedure, methods and matters of attention using 8.1.4 clause.

With the development of finite element method, it has become a trend for the design of electrothermal tank, but the finite element analysis method and checking criterion of electrothermal tank have not formed the industry standard. Based on the stress analyzing of electrothermal tank, a method is proposed that according to the stress classification of pressure vessel, linearize the finite element analysis results of the tank and check it with the corresponding standards.

This paper analyzed the key factors and their internal relations which influence the heat transfer capacity and efficiency of air conditioning heat exchangers, through the analysis of thermodynamic theory and the verification of the actual matching of the system. And this paper also analyzed and compared the resistance characteristics and the variation rules of the refrigerant flow of current heat exchanger, and provided some references for the system design of the heat exchanger.

Modal analysis of air conditioning system is used in air conditioning pipeline design as a guiding role. In this paper, with the idea of hybrid modeling by computing the experimental modal and the finite element modal of the compressor part of the air conditioning outdoor unit, the substructure hybrid modeling method based on the frequency response function is used to calculate the overall modal of the air conditioning system. Compared with the traditional finite element model, the modal frequency is more accurate, the error in 200Hz~300Hz frequency range is less than 2%, which provides reference value for the structure design.

The use of ohmic heating technology in soft thermal storage hand warmers has always been controversial. This product market proportion is big, and has a high unqualified rate in common sampling inspection, this situation has already affected the development of the industry. Our research is based on validation tests with new and used samples, we find that the hand warmers are electrical safe when using ohmic heating technology, the corrosion of the electrode has a positively relationship to the used times, they have a stable erosion process. The average first failure time meets the expected use, we adopt questionnaires method to get the required data and replace the old with the new from the users, it can be seen that the ohmic heating technology used for hand warmers has certain applicability.

The reasons for the ignition failure of the gas wall hanging furnace are analyzed from the aspects of theory, mechanism and experiment, and the preventive measures that need to be controlled in the design are also given.

In this paper, beef was used as the research object. After 28 days of experiment with fresh refrigerator and ordinary refrigerator, analysis the beef with the sensory evaluation, color change, freshness detection and microstructure: the score of overall sensory of beef in fresh refrigerator was 19.4 points, the redness value is 13.29% lower than the first day, and the beef keep first stage fresh, the microstructure of muscle fiber bundle is closely. The sensory score of beef in ordinary refrigerator is 17.7 points, the redness value is reduced by 37.25% compared with the first day, the fresh stage of beef is secondary, and the microstructure of muscle fiber bundle has been loose. The experimental results show that the preservation effect of the fresh refrigerator is obviously better than that of the ordinary refrigerator, and the electric field strength is greater than 60V/m, which has obvious preservation effect on the micro-frozen food.