Akai LCT3285TAJ, Руководство по обслуживанию

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PRODUCT SAFETY NOTICE
Many electrical and mechanical parts in this TV
receiver have special safety-related characteristics.
These characteristics are offer passed unnoticed by
visual spection and the protection afforded by them
cannot necessarily be obtained by using replacement
components rates for a higher voltage, wattage, etc.
The replacement parts which have these special
safety characteristics are identified by
marks on
the schematic diagram and on the parts list.
Before replacing any of these components, read the
parts list in this manual carefully. The use of
substitute replacement parts which do not have the
same safety characteristics as specified in the parts
list may create shock, fire, X-RAY RADIATION or
other hazards.
Good earth ground
such as the wat er
pipe, c onduc t or,
etc. Place this probe
on eac h e x -
pos ed met allic
part
AC VOLTMETER
AC Leak age Curr ent Check
4. Completely discharge the high potential voltage of the
picture tube before handling. The picture tube is a
vacuum and if broken, the glass will explode.
5. When replacing a MAIN PCB in the cabinet, always
be certain that all protective are installed properly
such as control knobs, adjustment covers or shields,
barriers, isolation resistor networks etc.
6. When servicing is required, observe the original lead
dressing. Extra precaution should be given to assure
correct lead dressing in the high voltage area.
7. Keep wires away from high voltage or high tempera
ture components.
8. Before returning the set to the customer, always
perform an AC leakage current check on the exposed
metallic parts of the cabinet, such as antennas,
terminals, screwheads, metal overlay, control shafts,
etc., to be sure the set is safe to operate without
danger of electrical shock. Plug the AC line cord
directly to the AC outlet (do not use a line isolation
transformer during this check). Use an AC voltmeter
having 5K ohms volt sensitivity or more in the
following manner.
Connect a 1.5K ohm 10 watt resistor paralleled by a
0.15µF AC type capacitor, between a good earth
ground (water pipe, conductor etc.,) and the exposed
metallic parts, one at a time.
Measure the AC voltage across the combination of
the 1.5K ohm resistor and 0.15 uF capacitor. Reverse
the AC plug at the AC outlet and repeat the AC
voltage measurements for each exposed metallic
part.
The measured voltage must not exceed 0.3V RMS.
This corresponds to 0.5mA AC. Any value exceeding
this limit constitutes a potential shock hazard and
must be corrected immediately.
The resistance measurement should be done
between accessible exposed metal parts and power
cord plug prongs with the power switch "ON". The
resistance should be more than 6M ohms.
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