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WARTUNG UND REPARATUR
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11 Safety
The unit may only be tampered with by qualified personnel in compliance with the applicable regulations.
Before removing parts of the housing, the unit must be switched off and disconnected from the mains.
When carrying out maintenance work on the open, live unit, bare circuit parts and metal semiconductor
housings must not be touched either directly or with a non-insulated tool.
For maintenance and repair of the safety-relevant parts of the unit, only replacement material according
to the manufacturer's specifications may be used.
In the event of faults in the SMPS-12 power supply, always replace the entire power supply unit. This
power supply unit contains several safety-relevant components. In addition, an accurate check requires
complex measurement technology.
11.1 Electrostatic Discharge (ESD)
Integrated circuits and other semiconductors are sensitive to electrostatic discharge (ESD). Improper
handling of assemblies with such components during maintenance and repair can impair their technical
properties or service life or lead to total failure.
The following rules must therefore be observed when handling ESD-sensitive components :
ESD-sensitive components may only be stored and transported in packaging intended and designated for
this purpose.
Unpackaged ESD-sensitive components may only be handled in the protective zones set up for this
purpose (EPA, e.g. area for field service, repair or service station) and may only be touched by persons
who are connected to the earth potential of the repair or service station. The serviced or repaired unit as
well as tools, aids, EPA-suitable (electrically semi-conductive) work, storage and floor mats must also be
in contact with metallic surfaces (shock discharge hazard).
To avoid undefined transient stress on the components and their possible damage due to unauthorised
voltage or equalising currents, electrical connections may only be made or disconnected when the unit is
switched off and after any capacitor charges have dissipated.