By simply moving, a person generates static electricity. Under these circumstances, coming in contact with a conductive material will discharge static from the body very quickly. This is ESD = Electrostatic discharge. Static electricity has become a big problem for the electronic manufacturing industry. Typically, no one notices because people don’t feel discharges under 3000 volts. Over 5000 volts, we may see ESD as a spark. The most sensitive components may be damaged by a charge of merely 30 volts, and a lot of standard 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 handful of essential tips for measuring all the parts of your ESD workstation.
- · When measuring 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 top edge.
- · With tables and shelves, place one probe on the work surface and the other on the table or shelf. The point-to-point resistance should be < 1x10⁹ Ω
- · For flooring, place one probe on your work surface and one probe on the ESD floor. Your point-to-point resistance should be < 1x10⁹ Ω
- · To test the common point ground, place the probe on the tabletop and measure the system’s total resistance between the tabletop and the common point ground using a measuring lead.
- · With chair ESD, place one probe on the seat of the chair and the other 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, be sure chair wheels are cleaned with ESD detergent.