Xerox WorkCentre C2424/DX, Руководство по обслуживанию

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Service Manual vii
Electrostatic Discharge (ESD) Precautions
Some semiconductor components, and the respective sub-assemblies that contain them, are
vulnerable to damage by Electrostatic Discharge (ESD). These components include Integrated
Circuits (ICs), Large-Scale Integrated circuits (LSIs), field-effect transistors and other
semiconductor chip components. The following techniques will reduce the occurrence of
component damage caused by static electricity.
Be sure the power is off to the chassis or circuit board, and observe all other safety precautions.
■
Immediately before handling any semiconductor components assemblies, drain the
electrostatic charge from your body. This can be accomplished by touching an earth
ground source or by wearing a wrist strap device connected to an earth ground source.
Wearing a wrist strap will also prevent accumulation of additional bodily static charges.
Be sure to remove the wrist strap before applying power to the unit under test to avoid
potential shock.
■ After removing a static sensitive assembly from its anti-static bag, place it on a grounded
conductive surface. If the anti-static bag is conductive, you may ground the bag and use it
as a conductive surface.
■ Do not use freon-propelled chemicals. These can generate electrical charges sufficient to
damage some devices.
■
Do not remove a replacement component or electrical sub-assembly from its protective
package until you are ready to install it.
■ Immediately before removing the protective material from the leads of a replacement
device, touch the protective material to the chassis or circuit assembly into which the
device will be installed.
■ Minimize body motions when handling unpackaged replacement devices. Motion such as
your clothes brushing together, or lifting a foot from a carpeted floor can generate enough
static electricity to damage an electro-statically sensitive device
■ Handle IC’s and EPROM’s carefully to avoid bending pins.
■ Pay attention to the direction of parts when mounting or inserting them on Printed Circuit
Boards (PCB’s).