Panasonic TH-60AS800S, Руководство по обслуживанию

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2 Warning
2.1 Prevention of Electrostatic Discharge (ESD) to
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 electrostatic discharge (ESD).
1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off
any ESD on your body by touching a known earth ground. Alternatively, obtain and wear a commercially
available discharging ESD wrist strap, which should be removed for potential shock reasons prior to applying
power to the unit under test.
2. 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.
3. Use only a grounded-tip soldering iron to solder or unsolder ES devices.
4. Use only an anti-static solder removal device. Some solder removal devices not classified as [anti-static (ESD
protected)] can generate electrical charge sufficient to damage ES devices.
5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ES devices.
6. Do not remove a replacement ES device from its protective package until immediately before you are ready to
install it. (Most replacement ES devices are packaged with leads electrically shorted together by conductive
foam, aluminum foil or comparable conductive material).
7. Immediately before removing the protective material from the leads of a 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 other safety precautions.
8. Minimize bodily motions when handling unpackaged replacement ES devices. (Otherwise ham less motion
such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate
static electricity (ESD) sufficient to damage an ES device).
2.2 About lead free solder (PbF)
Note: Lead is listed as (Pb) in the periodic table of elements.
In the information below, Pb will refer to Lead solder, and PbF will refer to Lead Free Solder.
The Lead Free Solder used in our manufacturing process and discussed below is (Sn+Ag+Cu).
That is Tin (Sn), Silver (Ag) and Copper (Cu) although other types are available.
This model uses Pb Free solder in it’s manufacture due to environmental conservation issues. For service and repair work,
we’d suggest the use of Pb free solder as well, although Pb solder may be used.
PCBs manufactured using lead free solder will have the PbF within a leaf Symbol
PbF stamped on the back of PCB.
Caution

Pb free solder has a higher melting point than standard solder. Typically the melting point is 50 ~ 70 °F (30~40
°C) higher. Please use a high temperature soldering iron and set it to 700 ± 20 °F (370 ± 10 °C).

Pb free solder will tend to splash when heated too high (about 1100 °F or 600 °C).
If you must use Pb solder, please completely remove all of the Pb free solder on the pins or solder area before
applying Pb solder. If this is not practical, be sure to heat the Pb free solder until it melts, before applying Pb
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