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SAFETY
PRECAUTIONS
GENERAL
GUIDELINES
1.
LEAKAGE CURRENT COLD CHECK
1
2.
TO
AC VOLTMETER
Hot-Check Circuit
COLD
WATER PIPE
(EARTH GROUND)
APPLIANCE'S
EXPOSED
METAL
PARTS
15002
10W
Figure
1
LEAKAGE
CURRENT
HOT
CHECK
(See Figure
1)
1.
2:
Plug the AC cord directly into the AC outlet.
at each point.
above measurements.
. The potantial at any point should
not exceed 0.75 volts
ELECTROSTATICALLY SENSITIVE( ES) DEVICES
Some semiconductor
(solid state) devices can be damaged
easily by static electricity. Such components commonly are
called Electrostatically sensitive (ES)
Devices. Examples of
typical ES devices are integrated circuits and some field-effect
transistors
and
semiconductor
"chip"
components.
The
following
techniques
should
be used
to help
reduce
the
incidence of component damage caused by static electricity.
1.
Immediately
before
handling
any
semiconductor
component or semiconductor-equipped assembly, drain off
any electrostatic charge on your body by touching a known
earth ground.
Alternatively, obtain and wear a commercially available
discharging wrist strap device, which should be removed
for potential shock reasons prior to applying power to the
unit under test.
. After removing an electrical assembly equipped with ES
devices, place the assembly on a conductive surface such as
aluminum foil, to prevent electrostatic charge buildup or
exposure of the assembly.
. Use only a grounded
tip soldering
iron
to solder
or
unsolder ES devices.
. Use only an anti-static solder removal device classified as
"anti-static" can generate electrical charges sufficient to
damage ES devices.
. Do not use freon-propelled chemicals. These can generate
electrical charges sufficient to damage ES devices.
. Do not remove a replacement ES device from its protective
package untilimmediately before you are ready to instal!
it. (most replacement ES devices are packaged with leads
electrically
shorted
together
by
conductive
foam,
aluminum foil or comparable conductive material).
. Immediately before removing the protective material from
the leads of replacement ES device, touch the protective
material to the chassis or circuit assembly into which the
device will be installed.
CAUTION:
Be sure no power is applied to the chassis or
circuit, and observe all otner asfety precautions.
. Minimize
bodily
motions
when
handling
unpackaged
replacement ES devoces. (Otherwise harmless mother such
as the brushing together of your clothes fabric or the lifting
of your foor from
a carpeted
floor can
generate static
electricity sufficient to damage an ES device).
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