Just by moving, a person makes static electricity. Under these circumstances, touching a conductive material will discharge static from you very rapidly. This is ESD = Electrostatic discharge. Static electricity is a big problem for electronics manufacturers. Normally, this passes unnoticed because we don’t feel electrostatic discharges under 3000 volts. We may see ESD beyond 5000 volts as a spark. Extremely sensitive electronic components can be damaged by a charge of only 30 volts, and some standard electronic components are sensitive to charges of 100 – 200 volts. When manufacturing electronic equipment, it’s essential to measure your ESD control regularly and correctly.
Below are a few essential tips for measuring all elements of your ESD workstation.
- · When you measure your ESD control on your work surface, place your probes on the tabletop, at least 25 cm apart and at least 5 cm from the top edge.
- · With shelves and tables, place one probe on the work surface and one probe on the shelf. Your point-to-point resistance should be < 1x10⁹ Ω
- · For flooring, put one probe on your work surface and the other on the ESD floor. The point-to-point resistance should be < 1x10⁹ Ω
- · Test the common point ground by placing the probe on your tabletop and measure the system’s total resistance between the tabletop and the common point ground using a measuring lead.
- · For chair ESD, place one probe on the seat of the chair and the other on a metal plate under one of the chair’s wheels. The point-to-point resistance should be < 1x10⁹ Ω (with upcoming standard < 1x1010 Ω). For best results, be sure chair wheels have been cleaned with ESD detergent.