Kongsberg Simrad SN90, Руководство по установке

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sparks require a field strength above approximately 4 kV/cm in air, as notably
occurs in lightning strikes. Other forms of ESD include corona discharge from
sharp electrodes and brush discharge from blunt electrodes.
ESD can cause a range of harmful effects of importance in industry, including gas,
fuel vapour and coal dust explosions, as well as failure of solid state electronics
components such as integrated circuits. These can suffer permanent damage
when subjected to high voltages. Electronics manufacturers therefore establish
electrostatic protective areas free of static, using measures to prevent charging,
such as avoiding highly charging materials and measures to remove static such as
grounding human workers, providing antistatic devices, and controlling humidity.
http://en.wikipedia.org/wiki/Electrostatic_discharge (January 2014)
Precautions to prevent Electrostatic Discharge (ESD)
Sensitive printed circuit boards and electronic modules must always be transported and
stored in protective antistatic packing bags. The circuit boards and modules must not be
transported or stored close to strong electrostatic, electromagnetic or radioactive fields.
If it is necessary to open and touch the printed circuit board or module inside the
protective bag, the following precautions must be taken:
1 The working area must be covered by an approved conductive service mat that has
a resistance of between 50 kΩ and 2 MΩ, and is connected directly to a reliable
earth point via its earthing cord.
2 You - and all other service personnel involved - must wear a wristband in direct
contact with the skin. The wristband must be electrically connected to the service
mat.
3 Printed circuit boards and electronic modules must be placed on the conductive
service mat during installation and maintenance operations.
4 If, for any reason, it is necessary to move the circuit board from the conductive
service mat, it must be placed in an approved antistatic transportation container (for
example a static shielding bag) before transportation.
5 During installation and servicing, all electrical equipment (for example soldering
irons and test equipment) must be earthed.
Related topics
Packing instructions for storage or shipping, page 266
Circuit board unpacking and handling, page 270
Returning a printed circuit board or an electronic module to Kongsberg Maritime,
page 272
Simrad SN90