Chapter 1. Important Service Safety Pre- Caution Important Service Safety Pre- Caution - Sharp LC-46XD1E/RU Service Manual

LC-46/52XD1E-RU
CHAPTER 1.
LC-46/52XD1E-RU
IMPORTANT SERVICE SAFETY PRECAUTION
[1] IMPORTANT SERVICE SAFETY PRECAUTION
Service work should be performed only by qualified service technicians who are thoroughly familiar with all safety checks and the
servicing guidelines which follow:
1. WARNING
1. For continued safety, no modification of any circuit should be attempted.
2. Disconnect AC power before servicing.
C A U T I O N : F O R C O N T I N U E D PROTECTION AGAINST A RISK OF
FIRE REPLACE ONLY WITH SAME TYPE
F701 (4A / 250V)
2. BEFORE RETURNING THE RECEIVER (Fire & Shock Hazard)
Before returning the receiver to the user, perform the following safety checks:
1. Inspect all lead dress to make certain that leads are not pinched, and check that hardware is not lodged between the chassis and other metal parts
in the receiver.
2. Inspect all protective devices such as non-metallic control knobs, insulation materials, cabinet backs, adjustment and compartment covers or
shields, isolation resistor-capacitor networks, mechanical insulators, etc.
3. To be sure that no shock hazard exists, check for leakage current in the following manner.
• Plug the AC cord directly into a 220 - 240 volt AC outlet. (Do not use an isolation transformer for this test).
• Using two clip leads, connect a 1.5k ohm, 10 watt resistor paralleled by a 0.15μF capacitor in series with all exposed metal cabinet parts and a
known earth ground, such as electrical conduit or electrical ground connected to an earth ground.
• A true RMS reading multimeter should be used for this test, especially where the equipment uses a switch mode power supply which may result in
very non-sinusoidal leakage current.
• Connect the resistor connection to all exposed metal parts having a return to the chassis (antenna, metal cabinet, screw heads, knobs and control
shafts, escutcheon, etc.) and measure the AC voltage drop across the resistor.
All checks must be repeated with the AC cord plug connection reversed. (If necessary, a nonpolarized adaptor plug must be used only for the pur-
pose of completing these checks.)
Any reading of 1.75 Vrms (this corresponds to 0.7 mA. peak AC.) or more is excessive and indicates a potential shock hazard which must be cor-
rected before returning the monitor to the owner.
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SAFETY NOTICE
Many electrical and mechanical parts in LCD color television have special safety-related characteristics. These characteristics are often not evident
from visual inspection, nor can protection afforded by them be necessarily increased by using replacement components rated for higher voltage, watt-
age, etc. Replacement parts which have these special safety characteristics are identified in this manual; electrical components having such features
are identified by " " . For continued protection, replacement parts must be identical to those used in the original circuit.
The use of a substitute replacement parts which do not have the same safety characteristics as the factory recommended replacement parts shown
in this service manual, may create shock, fire or other hazards.
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Service Manual
DVM
AC SCALE
1.5k ohm
10W
0.15 μ F
TEST PROBE
TO EXPOSED CONNECT TO
METAL PARTS KNOWN EARTH
GROUND
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