Areva MiCOM P225, Техническое руководство

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P225/EN IN/B11 Installation Guide
Page 4/12 MiCOM P225
2. HANDLING ELECTRONIC EQUIPMENT
The usual movements of a person easily generate electrostatic energy which may reach
several thousand volts. The discharging of this voltage into devices comprising
semiconductors, when handling electronic circuits, can cause severe deterioration. Such
damage is not necessarily visible immediately. Nevertheless, it reduces the reliability of the
circuit.
Electronic circuits are completely protected against any electrostatic discharge when inside
their housing. Do not expose them to any risk by needlessly taking the modules out of their
housings.
Each module has the best possible protection for its devices consisting of semiconductors.
However, should it be necessary to withdraw the module from its housing, please take the
following precautions to preserve the great reliability and long service life for which the
equipment was designed and manufactured.
1. Before taking the module out of its housing, touch the housing to balance your
electrostatic potential.
2. When handling the module, hold it by its front plate, or by its frame or by the edges of
the printed circuit board. Do not touch the electronic components, the printed circuit
conductors and the connectors.
3. Before passing the module to another person, shake hands with him or her for
example to balance your electrostatic potential.
4. Place the module on an antistatic surface or an electrically conductive surface with the
same potential as yourself.
5. To store or transport the module, place it in conductive packaging.
If you carry out any measurements on the internal electronic circuits of a device in service,
earth yourself to exposed conductive parts by linking yourself to the housing by a conductive
strap attached to your wrist. The resistance to earth of the conductive strap which you
attach to your wrist and to the housing must be between 500 k
Ω
and 10 M
Ω
. If you do not
have a device of this type, you must remain permanently in contact with the housing to
prevent any static energy accumulating. The instruments used to take the measurements
must be earthed to the housing insofar as this is possible.
For further information on the procedures for safe working with all the electronic equipment,
please consult standards BS5783 and IEC 147-OF. In a special handling area we strongly
advise you to undertake a detailed analysis of the electronic circuits and working conditions
according to the BS and IEC standards mentioned above.