How to effectively solve the grounding problem of anti-static chair
Customers who purchase anti-static chairs often complain that their anti-static properties are unstable, resulting in static discharge. After a specific analysis, the main reason is that the anti-static chair does not have a good grounding. The question is, how to properly ground the anti-static chair?
According to the requirements of ESD S20.20, the resistance value of the anti-static chair should be less than 109Ω. In the ESD STM 12.1 chair resistance monitoring test, it is necessary to test the resistance of the chair, seat back, armrest and the like to the wheel. If the wheel is made of an insulating material, it is certainly not satisfactory because the electrical resistance of the insulating material is greater than 10E12 Ω.
There are two ways to solve this problem: replacing the wheel and replacing the wheel with conductive wheels or dissipative materials; another method is to ground the antistatic chair with a grounding strap. If the latter is chosen, the chain must be attached to the chair's conductive or dissipative material to ensure that the grounding chain actually works. At the same time, the chain must have a certain length to ensure that it can be grounded through an anti-static floor. Through the chair grounded by the chain, it is only necessary to test the resistance value of the grounding chain of each part of the chair to meet the requirements.