Generally speaking, it is impossible not to generate static electricity, but sometimes static electricity is not enough to cause harm. The real danger is the accumulation of static electricity and the resulting electrostatic discharge. Therefore, the key to prevent static electricity is how to keep the electrostatic voltage in these places safe. VOLAB Wollebo's editor will discuss how to effectively prevent static electricity in the laboratory today. What is a good solution?
In the production process of electronic instruments, measures such as grounding, electrostatic leakage, dissipation, neutralization, humidification and shielding are often taken to prevent and suppress the generation and accumulation of electrostatic as much as possible, or to eliminate the accumulation of electrostatic quickly, safely and effectively in order to protect the destruction of electrostatic.
Temperature and humidity control:
From the data in the table, it can be seen that the environmental humidity has a great influence on the static voltage generated by human activities, and the relative environmental humidity in the electrostatic protection zone should be controlled at more than 40%. When the process conditions are allowed, air conditioning humidifiers and sprayers can be installed to improve the relative humidity of the air.
In addition, when the absolute humidity is constant, the higher the temperature, the lower the relative humidity in the area. Therefore, keeping a lower temperature is conducive to electrostatic protection.
Good grounding system:
Anti-static grounding system is a grounding access channel for grounding leakage. It is an electrical connection system that introduces grounding fees to the ground in turn from the working areas of ground, wall, worktable, equipment, instrument, wristband and so on.
In order to effectively prevent the harm of static electricity, it is necessary to provide channels for all conductors (including personnel) in the environment of static electricity protection, so that static electricity can be discharged in a short time (such as 0.1 seconds) in a timely and safe manner. Reliable grounding provides "equipotential" effect, which effectively reduces the damage of static electricity to electrostatic sensitive devices.
In short, all objects in contact with equipment, including space, should take anti-static measures to form a complete electrostatic protection area.
The grounding resistance of the independent and reliable grounding device of the system should be less than 10 ohms (the anti-static ground should not bear the force of zero line, and should not be grounded with lightning protection. If the three-phase five-wire system is used for power supply, it can be used as the anti-static ground of the geodesic line, but the zero line and the ground should not be mixed). The grounding area should be less than 100, and the cross-sectional area of a trunk should be less than 6, and the grounding line of the equipment and the worktable should be used No less than 1.25 by multiple strands using plastic grounding wire color green and yellow as the main wiring mode should be brazed. The underground conductors for laboratory use are shown in the figure. The special ground wire should be buried on the damp side of the building. The ground wire can be 600-700 mm long, 400-500 mm wide and 4-5 mm thick. The lead wire should be brazed on the copper plate. The cross-section area of the flat copper wire should not be less than 100 mm2 <