Samsung T220 - SyncMaster - 22" LCD Monitor, Руководство по обслуживанию

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1. Precautions 1. Precautions
1-2. Servicing Precautions 1-2. Servicing Precautions
WARNING: WARNING: An elec An elec trolytic trolytic capacitor capacitor installed with installed with the wr the wr ong polarity ong polarity might ex might ex plode. plode.
Caution: Caution: Before servicing units covered by this service manual, read and follow Before servicing units covered by this service manual, read and follow the Safety Precautions section of the Safety Precautions section of
this manual. this manual.
Note: Note: If unforeseen circumstances create conict between the following servicing precautions and any of the If unforeseen circumstances create conict between the following servicing precautions and any of the
safety precautions, always follow the safety precautions, always follow the safety precautions. safety precautions.
1-2-1 General Servicing Precautions 1-2-1 General Servicing Precautions
Always unplug the unit’s Always unplug the unit’s AC power cord from th AC power cord from th e AC pow e AC pow er source and disconnec er source and disconnec t the DC Power Jack t the DC Power Jack before before
attempting to: attempting to:
(a) remove or reinstall any component or assembly, (b) disconnect PCB plugs or connectors, (c) connect a test (a) remove or reinstall any component or assembly, (b) disconnect PCB plugs or connectors, (c) connect a test
component in parallel component in parallel with an electrolytic capacitor. with an electrolytic capacitor.
Some components are raised above the printed circuit board Some components are raised above the printed circuit board for safety for safety . An insulation tube or tape i . An insulation tube or tape i s sometimes s sometimes
used. The internal wiring is sometimes clamped to prevent contact with thermally hot used. The internal wiring is sometimes clamped to prevent contact with thermally hot components. Reinstall all such components. Reinstall all such
elements to their original position. elements to their original position.
After servicing, alway After servicing, alway s check that the sc s check that the sc rews, components rews, components and wiring have been correct and wiring have been correct ly reinstalled. Make sure th ly reinstalled. Make sure th at at
the area around the serviced part has not been damaged. the area around the serviced part has not been damaged.
Check the insulation between the blades of Check the insulation between the blades of the AC plug and accessible conductive parts (examples: metal panels, the AC plug and accessible conductive parts (examples: metal panels,
input terminals and earphone jacks). input terminals and earphone jacks).
Insulation Checking Procedure: Disconnect the power cord from the AC source and turn the power switch ON. Insulation Checking Procedure: Disconnect the power cord from the AC source and turn the power switch ON.
Connect an insulation resistance meter (500 V) to Connect an insulation resistance meter (500 V) to theblades of the AC plug. theblades of the AC plug.
The insulation resistance between each blade of The insulation resistance between each blade of the AC plug and accessible conductive parts (see above) should be the AC plug and accessible conductive parts (see above) should be
greater than 1 megohm. greater than 1 megohm.
Always connect a Always connect a test instrument’s gr test instrument’s gr ound lead to the instrument chass ound lead to the instrument chass is ground before connecting the pos is ground before connecting the pos itive lead; itive lead;
always remove the instrument’s ground lead last. always remove the instrument’s ground lead last.
1-3. Static Electricity Precautions 1-3. Static Electricity Precautions
Some semiconductor (solid state) devices can be Some semiconductor (solid state) devices can be easily damaged by static easily damaged by static electricity electricity . Such components are . Such components are commonly commonly
called Electrostatically Sensitive Devices (ESD). Examples of typical ESD called Electrostatically Sensitive Devices (ESD). Examples of typical ESD are integrated circuits and are integrated circuits and some eld-effect some eld-effect
transistors. The following techniques will transistors. The following techniques will reduce the incidence of reduce the incidence of component damage caused by static component damage caused by static electricity electricity . .
Immediately before handling any Immediately before handling any semiconductor components or assemblies, drain the electrostatic charge semiconductor components or assemblies, drain the electrostatic charge from your from your
body by touching a body by touching a known earth ground. Alternatively known earth ground. Alternatively , wear a , wear a discharging wrist-strap device. T discharging wrist-strap device. T o avoid a o avoid a shock hazard, shock hazard,
be sure to remove the wrist strap be sure to remove the wrist strap before applying power to the before applying power to the monitor. monitor.
After removing an ESD After removing an ESD -equipped assembly -equipped assembly , place it on a conductive surfa , place it on a conductive surfa ce such as aluminum ce such as aluminum foil to prevent foil to prevent
accumulation of an electrostatic charge. accumulation of an electrostatic charge.
Do not use freon-propelled chemicals. These can generate electrical charges sufcient to damage ESDs. Do not use freon-propelled chemicals. These can generate electrical charges sufcient to damage ESDs.
Use only a grounded-tip soldering iron Use only a grounded-tip soldering iron to solder or desolder ESDs. to solder or desolder ESDs.
Use only an anti-static solder removal device. Some solder removal devices not classied as “anti-static” can generate Use only an anti-static solder removal device. Some solder removal devices not classied as “anti-static” can generate
electrical charges sufcient to damage electrical charges sufcient to damage ESDs. ESDs.
Do not remove a replacement ESD from its protective package until you Do not remove a replacement ESD from its protective package until you are ready to install it. are ready to install it. Most replacement ESDs Most replacement ESDs
are packaged with leads that are are packaged with leads that are electrically shorted together by conductive foam, aluminum foil or other electrically shorted together by conductive foam, aluminum foil or other conductive conductive
materials. materials.
Immediately before removing the protective material from the leads of Immediately before removing the protective material from the leads of a replacement ESD, touch the protective a replacement ESD, touch the protective
material to the chassis or circuit assembly into which the material to the chassis or circuit assembly into which the device will be installed. device will be installed.
Caution: Caution: Be sure no Be sure no power is applied to the power is applied to the chassis or circuit and observe all other safety precautions. chassis or circuit and observe all other safety precautions.
Minimize body motions when handling Minimize body motions when handling unpackaged replacement ESDs. Motions such as brushing unpackaged replacement ESDs. Motions such as brushing clothes together, clothes together,
or lifting your foot or lifting your foot from a carpeted oor can generate enough from a carpeted oor can generate enough static electricity to damage an ESD. static electricity to damage an ESD.
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