Just by moving, a person generates static electricity. When this happens, coming in contact with a conductive material will cause a fast discharge of static from the body. This is called ESD = Electrostatic discharge. Static electricity is a big problem in the electronic manufacturing industry. Usually, this goes unnoticed because we don’t feel discharges below 3000 volts. We may see ESD over 5000 volts as a spark. Sensitive components may be damaged by a charge of merely 30 volts, and a lot of standard electronic components are sensitive to charges of 100 – 200 volts. When manufacturing electronic equipment, it’s vital to measure your ESD control regularly and correctly.
Below are a handful of essential tips to measure all components of your ESD workstation.
- · When you measure your ESD control on your work surface, place your probes on the tabletop, spaced at least 25 cm apart and at least 5 cm from the edge of the top.
- · For tables and shelves, place one probe on the work surface and the other on the shelf or table. The point-to-point resistance should be < 1x10⁹ Ω
- · For flooring, put one probe on the work surface and one probe on the ESD floor. Your point-to-point resistance should be < 1x10⁹ Ω
- · Test the common point ground by placing the probe on the tabletop and measure the system’s total resistance between the tabletop and the common point ground using a measuring lead.
- · Chair ESD, place one probe on the seat of the chair and one probe on a metal plate under one of the chair’s wheels. Point-to-point resistance should be < 1x10⁹ Ω (with upcoming standard < 1x1010 Ω). For best results, ensure chair wheels are cleaned with ESD detergent.