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1 Precautions


1 Precautions
Follow these safety, servicing and ESD precautions to prevent damage and to protect against potential hazards such as electrical shock.

1-1 Safety Precautions


1-1-1 Warnings
1. For continued safety, do not attempt to modify the
circuit board.
2. Disconnect the AC power and DC Power Jack before
servicing.
1-1-2 Servicing the LCD Monitor
1. When servicing the LCD Monitor Disconnect the AC
line cord from the AC outlet.
2. It is essential that service technicians have an accurate
voltage meter available at all times. Check the
calibration of this meter periodically.

1-1-3 Fire and Shock Hazard
Before returning the monitor to the user, perform the Figure 1-1. Leakage Current Test Circuit
following safety checks:
1. Inspect each lead dress to make certain that the leads
are not pinched or that hardware is not lodged between
1-1-4 Product Safety Notices
the chassis and other metal parts in the monitor. Some electrical and mechanical parts have special
2. Inspect all protective devices such as nonmetallic safety-related characteristics which are often not evident
control knobs, insulating materials, cabinet backs, from visual inspection. The protection they give may not
adjustment and compartment covers or shields, be obtained by replacing them with components rated for
isolation resistor-capacitor networks, mechanical higher voltage, wattage, etc. Parts that have special safety
insulators, etc. characteristics are identified by on schematics and parts
lists. A substitute replacement that does not have the same
3. Leakage Current Hot Check (Figure 1-1): safety characteristics as the recommended replacement part
WARNING: Do not use an isolation might create shock, fire and/or other hazards. Product
transformer during safety is under review continuously and new instructions
this test. are issued whenever appropriate.
Use a leakage current tester or a metering system that
complies with American National Standards Institute
(ANSI C101.1, Leakage Current for Appliances), and
Underwriters Laboratories (UL Publication UL1410,
59.7).




1-1
1 Precautions

1-2 Servicing Precautions
WARNING: An electrolytic capacitor installed with the wrong polarity might explode.
Caution: Before servicing units covered by this service manual, read and follow the Safety
Precautions section of this manual.
Note: If unforeseen circumstances create conflict between the following servicing precautions and any of the safety
precautions, always follow the safety precautions.



1-2-1 General Servicing 4. Check the insulation between the blades of the AC
plug and accessible conductive parts (examples: metal
panels, input terminals and earphone jacks).
Precautions 5. Insulation Checking Procedure: Disconnect the power
1. Always unplug the unit s AC power cord from the AC cord from the AC source and turn the power switch
power source and disconnect the DC Power Jack ON. Connect an insulation resistance meter (500 V) to
before attempting to: the blades of the AC plug.
(a) remove or reinstall any component or assembly, (b) The insulation resistance between each blade of the
disconnect PCB plugs or connectors, (c) connect a test AC plug and accessible conductive parts (see above)
component in parallel with an electrolytic capacitor. should be greater than 1 megohm.
2. Some components are raised above the printed circuit 6. Always connect a test instrument s ground lead to the
board for safety. An insulation tube or tape is instrument chassis ground before connecting the
sometimes used. The internal wiring is sometimes positive lead; always remove the instrument s ground
clamped to prevent contact with thermally hot lead last.
components. Reinstall all such elements to their
original position.
3. After servicing, always check that the screws,
components and wiring have been correctly
reinstalled. Make sure that the area around the
serviced part has not been damaged.

1-3 Static Electricity Precautions
Some semiconductor (solid state) devices can be easily damaged by static electricity. Such components are commonly called
Electrostatically Sensitive Devices (ESD). Examples of typical ESD are integrated circuits and some field-effect transistors.
The following techniques will reduce the incidence of component damage caused by static electricity.



6. Do not remove a replacement ESD from its protective
1. Immediately before handling any semiconductor package until you are ready to install it. Most
components or assemblies, drain the electrostatic replacement ESDs are packaged with leads that are
charge from your body by touching a known earth electrically shorted together by conductive foam,
ground. Alternatively, wear a discharging wrist-strap aluminum foil or other conductive materials.
device. To avoid a shock hazard, be sure to remove the 7. Immediately before removing the protective material
wrist strap before applying power to the monitor. from the leads of a replacement ESD, touch the
2. After removing an ESD-equipped assembly, place it protective material to the chassis or circuit assembly
on a conductive surface such as aluminum foil to into which the device will be installed.
prevent accumulation of an electrostatic charge. Caution: Be sure no power is applied to
3. Do not use freon-propelled chemicals. These can the chassis or circuit and
generate electrical charges sufficient to damage ESDs. observe all other safety
4. Use only a grounded-tip soldering iron to solder or precautions.
desolder ESDs.
8. Minimize body motions when handling unpackaged
5. Use only an anti-static solder removal device. Some
replacement ESDs. Motions such as brushing clothes
solder removal devices not classified as anti-static
together, or lifting your foot from a carpeted floor can
can generate electrical charges sufficient to damage
generate enough static electricity to damage an ESD.
ESDs.




1-2
1 Precautions

1-4 Installation Precautions
1. For safety reasons, more than two people are 6. Keep the antenna far away from any high-voltage
required for carrying the product. cables and install it firmly. Contact with the high-
voltage cable or the antenna falling over may
2. Keep the power cord away from any heat emitting cause fire or electric shock.
devices, as a melted covering may cause fire or
electric shock. 7. When installing the product, leave enough space
(10cm) between the product and the wall for
3. Do not place the product in areas with poor ventilation purposes.
ventilation such as a bookshelf or closet. The A rise in temperature within the product may
increased internal temperature may cause fire. cause fire.

4. Bend the external antenna cable when connecting
it to the product. This is a measure to protect it
from being exposed to moisture. Otherwise, it
may cause a fire or electric shock.

5. Make sure to turn the power off and unplug the
power cord from the outlet before repositioning
the product. Also check the antenna cable or the
external connectors if they are fully unplugged.
Damage to the cord may cause fire or electric
shock.




1-3
1 Precautions

Memo




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