PT2-E/G AVC1-U
SERVICING PRECAUTIONS
CAUTION: Before servicing instruments covered by thisElectrostatically Sensitive (ES) Devices
service data and its supplements and addenda, read andSome semiconductor (solid state) devices can be damaged
follow the ?Important Safety Instructions? on page 3 of thiseasily by static electricity. Such components commonly are
publication.called Electrostatically Sensitive (ES) Devices. Examples of
NOTE: If unforeseen circumstances create conflict betweentypical ES devices are integrated circuits and some field-
the following servicing precautions and any of the safetyeffect transistors and semiconductor ?chip? components. The
precautions on page 3 of this publication, always follow thefollowing techniques should be used to help reduce the
safety precautions. Remember: Safety First.incidence of component damage caused by static electricity.
General Servicing Guidelines1. Immediately before handling any semiconductor
1. Always unplug the instrument AC power cord from the ACcomponent or semiconductor-equipped assembly, drain
power source before:off any electrostatic charge on your body by touching a
a. Removing or reinstalling any component, circuitknown earth ground. Alternatively, obtain and wear a
board, module, or any other instrument assembly.commercially available discharging wrist strap device,
which should be removed for potential shock reasons
b. Disconnecting or reconnecting any instrumentprior to applying power to the unit under test.
electrical plug or other electrical connection.
2. After removing an electrical assembly equipped with ES
c. Connecting a test substitute in parallel with andevices, place the assembly on a conductive surface
electrolytic capacitor in the instrument.such as aluminum foil, to prevent electrostatic charge
buildup or exposure of the assembly.
CAUTION: A wrong part substitution or incorrect
polarity installation of electrolytic3. Use only a grounded-tip soldering iron to solder or
capacitors may result in an explosiondesolder ES devices.
hazard.
4. Use only can anti-static type solder removal device. Some
2. Do not spray chemicals on or near this instrument or anysolder removal devices not classified as ?anti-static? can
of its assemblies.generate electrical charges sufficient to damage ES
device.
3. Unless specified otherwise in these service data, clean
electrical contacts by applying the following mixture to the5. Do not use freon-propelled chemicals. These can
contacts with a pipe cleaner, cotton-tipped stick orgenerate electrical charges sufficient to damage ES
comparable nonabrasive applicator: 10% (by volume)devices.
Acetone and 90% (by volume) isopropyl alcohol (90%-
99% strength).6. Do not remove a replacement ES device from its
CAUTION: This is a flammable mixture. Unlessprotective package until immediately before you are ready
specified otherwise in these service data,to install it. (Most replacement ES devices are packaged
lubrication of contacts is not required.with leads electrically shorted together by conductive
foam, aluminum foil or comparable conductive material.)
4. Do not defeat any plug/socket of voltage interlocks with
which instruments covered by this service data might be7. Immediately before removing the protective material from
equipped.the leads of a replacement ES device, touch the
protective material to the chassis or circuit assembly into
5. Do not apply AC power to this instrument and/or any of itswhich the device will be installed.
electrical assemblies unless all solid-state device heat-CAUTION: Be sure no power is applied to the chassis or
sinks are correctly installed.circuit, and observe all other safety
precautions.
6. Always connect the test instrument ground lead to the
appropriate instrument chassis ground before connecting8. Minimize bodily motions when handling unpackaged
the test instrument positive lead. Always remove the testreplacement ES devices. (Otherwise harmless motion
instrument ground lead last.such as the brushing together of your clothes fabric or the
lifting of your foot from a carpeted floor can generate
7. Use with this instrument only the test fixtures specified instatic electricity sufficient to damage an ES device.)
this service data.
CAUTION: Do not connect the test fixture ground strap
to any heatsink in this instrument.
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ACEC
