1) Keep the temperature constant (temperature fluctuation is controlled within 24±1～2oC).
2) Keep the humidity constant (relative humidity fluctuation is controlled within 50%±5%RH).
3) Air cleanliness 0.5 microns/liter 4. Ventilation times/hour>30. That is, in a given computer room, the ratio of the air volume of the air conditioner to the volume of the computer room is greater than 30.
4) The positive pressure of the computer room is>10Pa.
5) High-precision constant temperature and humidity air conditioning equipment has remote monitoring and call self-starting functions.
For the computer room, to ensure the stability and reliability of the computer room environment, high-precision constant temperature and humidity air conditioning dedicated air conditioning is required. The use of ordinary air conditioning units only reduces the initial investment, but cannot guarantee the temperature and humidity environment required by the data center, and the total cost is higher than that of high-precision constant temperature and humidity air conditioning. Only high-precision constant temperature and humidity air conditioning can solve the reliable operation of the computer room. The following five problems cannot be solved by ordinary air conditioning, which is also the reason for using high-precision constant temperature and humidity air conditioning:
1) The impact of high temperature
It will cause the performance of electronic components to deteriorate and reduce the service life. It can change the expansion coefficient of the material. Precision machinery such as disk drives and tape drives often malfunction due to the influence of thermal expansion. It will accelerate the aging, deformation, and cracking of insulating materials, thereby reducing the insulation performance, and cause the softening of thermoplastic insulating materials and lubricating grease, causing malfunctions. When the temperature is too high and exceeds the allowable value of the temperature rise of the motor transformer winding, the motor will burn out.
2) The influence of low temperature
Low temperature can change the parameters of capacitors, inductors and resistors, which directly affects the stable operation of the computer. Low temperature may also cause grease and lubricating oil to solidify and freeze. Low temperature can cause poor contact between metal and plastic insulation parts due to different shrinkage coefficients, brittle materials, and cracking of individual sealed electronic components.
The large change in air temperature per unit time will cause internal stress in pipe fittings, accelerate mechanical damage and changes in electrical parameters of electronic components and certain materials. Rapid temperature changes will cause cracking, delamination, air leakage of seals, and peeling of potting materials from electronic components or packaging surfaces in certain joints, thereby creating gaps and deforming certain supports.
3) Effect of high humidity
When the moisture content in the air remains unchanged, the relative humidity increases as the air temperature decreases. When the relative temperature is close to 70%, some parts may have a slight condensation. If the water vapor is sucked into the pipe, it will change its internal electrical performance parameters, causing leakage and leakage of the path, resulting in breakdown and damage to electronic components. High humidity will cause oxidation and corrosion of metal materials, weaken the insulation strength of non-metallic components or insulating materials, age and deform the materials, and cause structural damage. High humidity will cause the tape to slip during operation, affect the stability of the tape drive, and cause instantaneous errors in the reading and writing of disks and tapes.
4) Effect of low humidity
The air in the computer room is dry, and low relative humidity is prone to static electricity. According to experimental tests, when the relative temperature is 30%, the static voltage is 5kV. When the relative humidity is 20%, the static voltage is 10kV. When the static voltage exceeds 2kV in the data center, it will cause the disk drive to fail, and it will also cause the tape to deform, warp and break. Static electricity can easily absorb dust. If it is stuck to the read and write heads of disks and tapes, data errors may occur at the least, and the disks may be scratched and the heads may be damaged at the worst. Static electricity in the computer room can also be felt by people. When the static voltage exceeds 1kV, the discharge process poses a threat to human safety.
5) Impact on the air environment
The impact of high-precision constant temperature and humidity air conditioners on the air environment can be divided into three categories: the impact of dust, the impact of harmful gases, and the impact of noise. The two types of dust that have a greater impact on data centers are mineral dust and dust fiber dust.
Mineral solid powder entering the computer room will scratch the surface protective layer of electronic equipment and the entire machine, and will also accelerate the wear of the moving parts of precision machinery, causing failures. Dust fiber dust is hygroscopic. If it is attached to electronic components, it can cause oxidation and corrosion of metal materials, change electrical parameters, and cause poor heat dissipation of electronic components and reduced insulation performance.