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How to control the balance of humidity and temperature in military power supply modules

During the production process of the module power supply, the humidity and temperature should be kept moderate, not too low or too low. Grasp the balance of temperature and humidity, so that the power module production can proceed normally, and ensure the quality of the power module and subsequent normal use.
If the power module is too humid, the moist air will enter the hollow and porous gaps of the electric board. The leakage path between the conductors is caused, oxygen is generated, and the moisture absorption of the parts reduces the resistance of the insulation, and the isolation withstand voltage is reduced. However, excessive drying can also make some materials brittle, rough surface, and even generate static electricity, so the production environment will also have a certain impact on the reliability of the power supply.
Most power modules solder the components on a small PCB board (printed circuit board), and then pot the small PCB board into the shell with resin. During the production process, if the production environment has high humidity, especially during the rainy season in the south, the moisture in the air will condense on the PCB board and components. Even when the resin is potted, the bubbles are removed by the vacuum defoaming process. The moisture on the PCB board and components cannot be removed.
When the power module is working at a higher ambient temperature, the moisture on the PCB board and components vaporizes and expands, causing cracks in the power module, breaking the internal transformer wire, or introducing external moisture, corroding the internal components of the power module or causing damage. The circuit inside the module is short-circuited. For occasions with higher isolation voltage requirements, the moisture on the PCB board and components will also reduce the isolation capability of the power module, and even cause breakdown between the primary and secondary, resulting in serious consequences.
Too low humidity will also cause too much dust to float in the air, which will affect the quality of the power module. The introduction of air conditioning systems and dehumidification systems in the production environment can keep the humidity in the production environment at an appropriate level and avoid adverse effects on the reliability of the power module due to moisture condensation or excessive air drying. Both high temperature and low temperature will affect the components to varying degrees. The temperature of the production environment also needs to be strictly controlled.
The high temperature environment will cause changes in electrical performance parameters such as resistance, inductance, capacitance, and electrical power series in the power supply, which will soften the insulator and cause insulation failure; movable components may become blocked due to expansion and cause structural failure, and the coating surface will bubble. Oxidation and other chemical reactions accelerate, lubricant viscosity decreases and evaporates and loses lubricity; due to physical expansion, the wear of moving parts increases and its structural strength decreases.
The low temperature environment will make the plastic and rubber of the power supply lose its flexibility and become brittle. When there is moisture, it will freeze, the lubricant will become gelatinous and sticky and lose its lubricity; the coating surface will be cracked; the structure will be caused by physical shrinkage Failure, change of electrical and mechanical functions, etc.
Power modules, especially small-sized 1W and 2W power modules, often use magnetic winding transformers with an inner diameter of less than 5mm. In the case of manual production only, frequent hand movements of the production staff during work will produce sweat and sweat on their hands. Will stay on the transformer, the moisture and salt in it will damage the varnish of the transformer, reduce the insulation capacity of the transformer, and cause potential impact on the reliability and other quality of the power module.
The power module is a combination of many electronic components and circuits. The good cooperation of each part of the module power supply can ensure the normal use and life of the electrical equipment and the power supply module products used. In the power module, the production and operation should be performed in a constant temperature and humidity environment as much as possible. Maintain good performance in every aspect of power production.