Anti-static wrist ring several principles
The wired anti-static wrist strap is used to introduce static electricity into the earth through an anti-static grounding wire through a 1 megaohm resistor and wire in the plastic box on the wristband. The series connection is mainly for personal safety considerations.
Three ways to discharge static electricity
Generally, there are three ways to handle static electricity;
1) Direct discharge means that the static electricity is discharged to the ground through the electrostatic wristband;
2) Neutralization by static and negative ions in the air and static electricity generated by itself;
3) The static electricity is consumed by the power consuming material;
As the flame heart said, the wired electrostatic ring is discharged through a 1M ohm resistor, so as to avoid the impact of the instantaneous high current on the component and avoid device damage!
In the test of the factory's electrostatic protection system, I found that some measures did not have the effect of anti-static. Such as anti-static chairs, anti-static logistics vehicles. There is no effect, just do the test. It can be tested by triboelectric test, and good things will not produce voltages higher than 10V.
The function of the 1M ohm resistor is to keep the impedance of the static power supply to the earth at a suitable resistance, so that the static electricity can be quickly discharged to the earth without generating excessive current, damaging the equipment, and people will not feel pain. sense. Others such as the ground, desktop, logistics vehicles, workstations, clothes, shoes, hats, gloves, etc. are the same.
The cordless wristband theory uses the principle of corona discharge to dissipate a part of static electricity. Corona discharge is also called tip discharge. After the body is charged, it usually needs a voltage of more than 1500V, and its tip part will discharge the air. Dissipates static electricity, but the static voltage required for dissipating static electricity in cordless wristbands is too high, and is not suitable for the electronics industry because there are many electronic components that can withstand high voltages above 1500V.
Therefore, the wireless bracelet does not have much practical use. It is not recommended.