Computer room air conditioning fresh air system

Computer room air conditioning fresh air system

The affected electronic components, mechanical components, and materials. If the environmental conditions cannot meet the usage requirements of these devices, it will reduce the reliability of the computer, accelerate the aging of components and materials, shorten the service life of the machine, and even lose important data and cause malfunctions.
The harsh environment not only affects the physical and mental health of electronic computer operators, but also affects work efficiency, causing operational errors, and in severe cases, endangering the safety of personnel and equipment. Therefore, it is very important to understand the role and impact of the environmental conditions in the computer room.GB2887-2000Divide the environmental conditions of the computer room intoA、BTwo level processing.
The impact of environmental conditions on computer rooms can be divided into temperature, humidity, dust, harmful gases, electromagnetic interference, etc.

Temperature influence

Among the various factors that affect microelectronic devices such as electronic computers, the influence of temperature and humidity is very important. If the large amount of heat generated by electronic components cannot be dissipated in a timely manner, causing the junction temperature of semiconductor devices to be too high, and the penetration current and current to continuously increase, it will cause thermal breakdown, resulting in the damage of semiconductor devices. Ultra high temperature will cause a decrease in the rated power of the resistor, increase the evaporation of moisture in the electrolyte of the electrolytic capacitor, reduce its capacity, and affect the change in its power factor. When the changes in resistance and capacitance values exceed the allowable range, it will cause the computer system to operate unstably and increase faults. The internal stress generated by severe expansion and contraction, as well as alternating condensation, freezing, and steaming, will accelerate the mechanical damage and electrical performance changes of components and materials. Magnetic tapes, disks, and other media used for input and output in electronic computers may experience the disappearance or inability to access important data if stored outside of specified environmental conditions.

The influence of humidity

Usually, when the relative humidity is below40%At that time, the air was considered dry; And when the relative humidity is higher than80%When, it is considered that the air is humid; When the relative humidity is100%At this point, the air is in a saturated state. When the relative humidity of the air is greater than65%When, the surface of the object adheres to a layer with a thickness of0.001～0.01 umWhen the air humidity reaches saturation, the thickness of the water film can increase to10umIn order to ensure the continuous and reliable operation of computer equipment, in addition to strict temperature control, humidity should also be controlled within the specified range. Abnormal relative temperature not only affects the reliability and lifespan of the equipment, but also makes the staff feel tired. The influence of humidity is that, under constant relative humidity, the higher the humidity, the greater the impact of water vapor on computer equipment. For external devices such as magnetic tapes and disks, high humidity will affect the high-speed operation of the magnetic head and cause the magnetic tape to slip. In low humidity conditions, static charges accumulate to varying degrees in many areas of the computer room. Static electricity not only causes computer equipment to malfunction and affects the physical and mental health of operators, but also causes great psychological anxiety and reduces work efficiency. The alternating environment of high temperature, high humidity, and low temperature drying, due to the breathing effect of material capillaries, will further accelerate the moisture absorption and corrosion process of materials, causing particularly serious harm to computer equipment. Therefore, the national standard "General Specification for Electronic Computer Room Sites" in China stipulates that the relative humidity inside the computer room during startup is:
ALevel:45%～65%?? BLevel:40%～70%
Relative humidity of the computer room during shutdown:ALevel:40%～70%? BLevel:20%～80%

The impact of dust

The concentration of dust in the atmosphere is related to factors such as regional pollution level, climate, temperature, time, and wind speed. Dust has a significant impact on computer equipment, especially on some precision devices and connectors. The disk storage is the most sensitive to dust in computers, and if dust enters the disk, it can cause damage“read”、“write”Error, although other components of the computer may seem to be operating normally at this time, they will also lose their meaning. In addition, dust deposited on electronic components such as integrated blocks will reduce the heat dissipation performance of the component; Dust can reduce the performance of insulation materials and even pose hazards such as short circuits. The amount of dust in the computer room is measured based on the number of dust particles per unit volume.
The sources of dust in the computer room are as follows:
1）When the fresh air system is delivering fresh air to the computer room, the accuracy of the filtering device is insufficient, and dust enters the computer room.
2）The air pressure in the computer room has not generated a certain positive pressure.
3）Dust is generated by staff working in the computer room.
4）Dust generated from the movement, replacement, handling, repair, and maintenance of equipment.
5）The enclosure structure of the computer room is not tight enough, and dust enters through gaps.
6）Dust is generated on the walls, ceilings, floors, and other parts of the computer room due to coating peeling.
7）When staff enter the computer room, dust is brought in from the outside.
We suggest that the dust prevention measures for the computer room include:
1）The decoration materials for the computer room are made of flame-retardant materials that do not absorb or emit dust.
2）Strictly handle the enclosure structure of the computer room.
3）Minimize the amount of dust generated by the equipment.
4）Staff members should wear dust-free work clothes when entering the computer room.
5）When the fresh air system is sent into the computer room, it undergoes high-efficiency or sub high efficiency filtration.

Harmful gas impact

The air composition in the computer room is mainly composed of nitrogen, oxygen, and a small amount of inert gases such as carbon dioxide, argon, krypton, neon, xenon, etc. Among them, air accounts for99.9%Among them0.1%It is composed of water vapor, corrosive gases, organic matter, and particles. The content of corrosive gases is very low, but it can also cause computer damage or misoperation. in compliance withSO2It is the largest reactant and produces sulfur-containing acids through small reactions, which can corrode many metal materials;NO2Neutralizing moisture in the air produces nitric acid, which affects the operation of equipment;O3Can corrode parts made of plastic, rubber products, etc., causing them to age and reduce their elasticityO3When infiltrating into semiconductors, it can also disrupt the stability of the base. Among numerous harmful gases,SO2andH2SThe greatest impact.