OEM7 Installation and Operation User Manual v4
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APPENDIX H
Electrostatic Discharge (ESD) Practices
Various electrical and electronic components are vulnerable to ESD. These include discrete com-
ponents, hybrid devices, Integrated Circuits (ICs) and Printed Circuit Boards (PCBs) assembled
with these devices.
H.1 Handling ESD Sensitive Devices
ESD sensitive devices must only be handled in static controlled locations. Some recom-
mendations for such handling practices follow:
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Handling areas must be equipped with a grounded table, floor mats and wrist strap.
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A relative humidity level must be maintained between 20% and 80% non-condensing.
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No ESD sensitive board or component should be removed from its protective package,
except in a static controlled location.
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A static controlled environment and correct static control procedures are required at both
repair stations and maintenance areas.
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ESD sensitive devices must be handled only after personnel have grounded themselves via
wrist straps and mats.
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Boards or components should never come in contact with clothing, because normal ground-
ing cannot dissipate static charges on fabrics.
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A circuit board must be placed into a static shielding bag or clamshell before being removed
from the work location and must remain in the protective enclosure until it arrives at a static
controlled repair/test center.
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Circuit boards must not be changed or moved needlessly. Handles may be provided on cir-
cuit boards for use in their removal and replacement; care should be taken to avoid contact
with the connectors and components.
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On-site repair of ESD sensitive equipment should not be undertaken except to restore ser-
vice in an emergency where spare boards are not available. Under these circumstances
repair station techniques must be observed. Under normal circumstances a faulty or suspect
circuit board must be sent to a repair center having complete facilities or to the man-
ufacturer for exchange or repair.
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Where protective measures have not been installed, a suitable alternative would be the use
of a Portable Field Service Grounding Kit (for example, 3M Kit #8501 or #8507). This con-
sists of a portable mat and wrist strap which must be attached to a suitable ground.
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A circuit board in a static shielding bag or clamshell may be shipped or stored in a cardboard
carton, but the carton must not enter a static controlled area such as a grounded or dis-
sipative bench top or repair zone. Do not place anything else inside the bag (for example,
repair tags).
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Treat all PCBs and components as ESD sensitive. Assume that you will damage the PCB or
component if you are not ESD conscious.
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Do not use torn or punctured static-shielding bags. A wire tag protruding through the bag
could act as a "lightning rod", funneling the entire charge into the components inside the bag.
