Testing Chambers Knowledge

  Environmental conditions are the key factors that affect the quality and reliability of equipment. For equipment used in the environment where the ambient air temperature changes rapidly, the impact of temperature shock environment is a factor that must be considered.  This environment brings a variety of typical environmental effects to equipment, such as deformation or fracture of parts, insulation protection failure, clamping or relaxation of moving parts, changes of electrical and electronic components electronic or mechanical failure caused by rapid condensation or frost. Whether the equipment can work normally under the temperature shock environment directly reflects the adaptability of the equipment to this environment. According to method 503.4 (temperature shock test) of American military standard ML-STD-810 F, equipment that may be deployed in the environment with rapid air temperature change shall undergo temperature shock test. The test chamber must have the abil...

  1.Volume Selection When the tested product (components, components, parts or complete machine) is placed in the climate environment chamber for testing, in order to ensure that the tested product The ambient atmosphere can meet the environmental test conditions specified in the test specifications. The following provisions shall be followed between the working dimension of the climate chamber and the external dimension of the tested product: a) The volume of the tested product (Wide x Deep x High) shall not exceed (20 ~ 35)% of the effective working space of the test chamber (recommended) 20%). It is recommended that no more than 10% of the products that generate heat in the test be selected.   b) The ratio of the windward sectional area of the tested product to the total area of the test chamber on the section shall not be greater than (35 ~ 50)% (push) Recommended 35%).   c) The distance between the outer surface of the test product and the wall of the test chamber sh...

  1.Test Overview The impact experienced by the products during use and transportation is mainly due to the impact caused by the emergency braking and impact of vehicles, the air drop and crash of aircraft (emergency landing), the launch of artillery, the explosion of chemical energy and nuclear energy, the ignition separation and re-entry of missiles and high-performance weapons. Impact is to apply a high-level input pulse force to the product in a relatively short time.   Impact is a very complex physical process. Like random vibration, it has a continuous frequency spectrum, but it is also a transient process and does not have the condition of steady-state random. After the product is impacted, the movement state of its mechanical system will change suddenly and produce transient impact response. The response of products to mechanical impact environment has the following characteristics: high frequency oscillation, short duration, obvious initial rise time and high-order po...

  When satellites, space probes and other spacecraft are operating in space, they are in a thermal vacuum environment of high vacuum, cold black and solar radiation. Vacuum thermal environment simulation test is a very effective ground test method to simulate the vacuum thermal environment (high vacuum, cold black, solar radiation, high temperature and other environments) of the space.   Vacuum thermal test is the general term of spacecraft thermal balance test and thermal vacuum test. The vacuum thermal environment simulation test of spacecraft has become one of the most important links in the development stage of spacecraft. It can test the rationality of the thermal control design of spacecraft such as satellites, modify the design model, verify the working state of instruments and equipment inside the spacecraft, as well as the matching and working performance between subsystems. At the same time, it can also be used to check the function and manufacturing process of space...

  1. Low Air Pressure Environment Due to the gravity of the earth, the air has a certain weight to form atmospheric pressure. The atmospheric pressure at a certain height is the heaviest of the entire air column on the unit area perpendicular to the ground above the point. With the increase of height, the air gradually becomes thinner and the atmospheric pressure gradually decreases.  According to the actual measurement, within 3000 km of sea level, the air pressure decreases by 100 Pa for every 10 meters of height increase, and the atmospheric pressure near 31 km is 1/100 of the standard atmospheric pressure at sea level. In addition to being related to altitude, atmospheric pressure is also related to weather changes. At the same place, the pressure is high in sunny days and low in overcast days, and the pressure in winter is higher than that in summer.   In China, about 50% of the earth’s surface area is 1000 m higher than the sea level, and about 25% of the area is 20...

  1.Overview High and Low Temperature Humidity Test Chamber  is a kind of equipment that can be used for the reliability test of lithium batteries, small electronic products, electronic components and materials, or for the climate test of other products. The temperature adjustment range of high and low temperature damp heat laboratory is generally +60 ℃ ~-50 ℃, and the relative humidity adjustment range: within +20 ℃ ~+40 ℃, the humidity is 50%~95% RH; Within +40 ℃ ~+60 ℃, the humidity is 30%~95% RH.  Because the temperature range is large and the negative temperature is low, the refrigeration system in the laboratory is relatively complex, so using the conventional relay control and manual operation methods is not only complex, but also inconvenient to operate. The high and low temperature laboratory control system designed by using the dry and wet bulb temperature control table and PLC can be operated manually and automatically. It is not only simple in circuit, but als...