Safety Precaution - Sharp LC-32LE260M Service Manual

LC-32LE260M

CHAPTER 1.

[1] IMPORTANT SERVICE SAFETY PRE-

CAUTION

LC

IMP OR TANT S E R VIC E S AF E T Y P R E C AUT ION

S ervice work s hould be performed only by qualified s ervice technicians who are thoroughly familiar with all s afety checks and the

s ervic ing guidelines which follow:

WAR NING

1. F or continued safety, no modification of any circuit should be

attempted.

2. Disconnect AC power before servicing.

B E F OR E R E T UR NING T HE R E C E IVE R (F ire &

S hock Hazard)

B efore returning the receiver to the us er, perform the following

s afety checks :

3. 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.

4. 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.

5. To be sure that no shock hazard exists, check for leakage current in

the following manner.

• P lug the AC cord directly into a 110-240 volt AC outlet.

• Using two clip leads, connect a 1.5k ohm, 10 watt resistor paral-

leled by a 0.15 F capacitor in series with all exposed metal cabinet

parts and a known earth ground, such as electrical conduit or elec-

trical ground connected to an earth ground.

• Use an AC voltmeter having with 5000 ohm per volt, or higher, sen-

sitivity or measure the AC voltage drop across the resistor.

• C onnect 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.

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S A F E T Y NOT IC E

Many electrical and mechanical parts in LC D colour television have

special safety-related characteristics.

T hese 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, wattage, etc.

R eplacement parts which have these special safety characteristics are

identified in this manual; electrical components having such features

are identified by "

" and shaded areas in the R eplacement P arts List

and S chematic Diagrams.

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All checks must be repeated with the AC cord plug connection

reversed. (If necessary, a nonpolarized adaptor plug must be used

only for the purpose of completing these checks.)

Any reading of 0.74 Vrms (this corresponds to 0.5 mA rms AC .) or

more is excessive and indicates a potential shock hazard which

must be corrected before returning the monitor to the owner.

T O E XP OS E D

ME T AL P AR T S

F or continued protection, replacement parts must be identical to those

used in the original circuit.

T he 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.

1 – 1

DVM

AC S C ALE

1.5k ohm

10W

0.15 µ F

T E S T P R OB E

C ONNE C T T O

K NOWN E AR T H

G R OUND