Static Electricity Solutions for Electronic Components
1. Safety
EPAs generally have powered tools and equipment. In such environments, it is dangerous to connect a single object or device directly to the ground. For this reason, a resistor of not less than 1M is inserted in series at the connection of the wristband grounding wire, the wheel, and the toe strap. Some wristband grounding wires have such a resistor at each end, so there is no danger even if the wristband grounding wire is connected to the live terminal of the powered repair product. The wristband grounding wire tester is an instrument that detects whether the resistance value of the resistor is appropriate (if it is too high, it is impossible to achieve equal potential connection; if it is too low, there will be a safety hazard). The wristband grounding wire should be equipped with a plug that can be quickly unplugged and is incompatible with other electrical sockets, so that it can be ensured that it will not be mistakenly plugged into other electrical sockets and can be easily unplugged in an emergency.
2. Actual work in the electrostatic discharge protection zone
In the electrostatic discharge protection zone, if clear working specifications are not followed, the charge and potential cannot be kept within the allowable range. Some examples of problems include: bringing documents, plastic containers, cups, etc. in non-antistatic plastic covers into the ESD protection area, and using cleaning agents that will destroy the electrostatic properties of the floor or work surface. The relevant personnel should receive adequate training to learn not only the procedures that need to be followed, but also understand the reasons why these procedures must be followed. It is also useful to understand the relevant parameters of the components that may be damaged. A dedicated person should be designated to be responsible for the care and maintenance of the ESD protection area, and the implementation of the procedures should also be checked. These checks should also be verified as part of the quality management system certification.
3. Transportation and storage
When transporting components with pins, conductive foam materials are usually used. This can prevent high potential differences between component pins. For components with dual in-line packages, static dissipative tubes are often used during bulk transportation. For circuit board components, when they are outside the ESD protection area, they should be placed in static shielding bags or conductive transport boxes for transportation. Some packaging bags are made of conductive materials, which can ensure that all components are at the same potential under stable conditions and dissipate static charges that accidentally run onto the bag. This method cannot be used for boards with batteries, for which a bag with a static dissipative lining and a conductive outer layer should be used. Such bags are more expensive but provide excellent protection for both powered and unpowered components. Likewise, a conductive box with rails inside to hold the board in place cannot be used with powered boards that have exposed connectors on the edge.