Static electricity

Static electricity is a set of phenomenon associated with the appearance, maintenance and relaxation of a free electric charge on the surface or in the volume of dielectrics or in insulated conductors.

Static charge is called an "invisible killer" for electronic components - static electricity accumulated on various subjects can lead to discharge at the most unexpected moment. In electronic industry the most sensitive components can fail even at the voltage of 30 V. When high-resistance materials get in contact only charge carriers, located close to the area of ​​contact, are involved in electrization. And they will remain at the same point in which they were originally formed even if the material is grounded. Static charges on non-grounded conductive materials (conductors) are distributed almost immediately across the whole surface of the contacting elements. If the conductive material is grounded static electricity quickly flows into the ground. This process is called ESD (Electro Static Discharge).

Characteristics of the materials concerning electrostatic discharge can be described with the help of the scale which indicates the surface resistance.