Siemens SIMATIC PANEL PC 877 - Manual (Page 267)

SIMATIC Panel PC 877
Operating instructions, Release 07/2006, A5E00877780-01
B-1
B
ESD directives
B
B.1
B.1
ESD guideline
What does ESD mean?
Almost all electronic modules are equipped with highly integrated components and elements
in MOS technology. For technological reasons, these electronic components are very
sensitive to overvoltages and, consequently, to electrostatic discharge. These components
are therefore marked as follows:
•
ESD: Electrostatically Sensitive Devices
• ESD: Internationally recognized marking for components and modules susceptible to
electrostatic discharge
The following symbols on switch cabinets, module carriers or packaging indicate their
susceptibility to electrostatic discharge:
ESD components are destroyed by voltage and energy far below the limits of human
perception. Voltages of this kind occur as soon as a device or an assembly is touched by a
person who is not electrostatically discharged ESD components which were subject to such
voltage are usually not recognized immediately as being defective, because the malfunction
does not occur until after a longer period of operation.
Note
More information is located on the rating plate. The rating plate is described in the chapter
"Planning use."