Sharp LC-15AV7U, Руководство по обслуживанию

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LCVISP
IMPORTANT SAFEGUARDS AND PRECAUTIONS
Safety Precautions for LCD TV Circuit
1. Before returning an instrument to the customer,
always make a safety check of the entire instrument,
including, but not limited to, the following items:
a. Be sure that no built-in protective devices are defective
and have been defeated during servicing.
(1) Protective shields are provided on this chassis to
protect both the technician and the customer.
Correctly replace all missing protective shields,
including any removed for servicing convenience.
(2) When reinstalling the chassis and/or other
assembly in the cabinet, be sure to put back in place
all protective devices, including but not limited to,
nonmetallic control knobs, insulating fishpapers,
adjustment and compartment covers/shields, and
isolation resistor/capacitor networks.
Do not operate
this instrument or permit it to be operated without
all protective devices correctly installed and
functioning. Servicers who defeat safety features
or fail to perform safety checks may be liable for
any resulting damage.
b. Be sure that there are no cabinet openings through
which an adult or child might be able to insert their
fingers and contact a hazardous voltage. Such
openings include, but are not limited to, (1) spacing
between the Liquid Crystal Panel and the cabinet
mask, (2) excessively wide cabinet ventilation slots,
and (3) an improperly fitted and/or incorrectly secured
cabinet back cover.
c. Antenna Cold Check - With the instrument AC plug
removed from any AC source, connect an electrical
jumper across the two AC plug prongs. Place the
instrument AC switch in the on position. Connect one
lead of an ohmmeter to the AC plug prongs tied
together and touch the other ohmmeter lead in turn
to each tuner antenna input exposed terminal screw
and, if applicable, to the coaxial connector. If the
measured resistance is less than 1.0 megohm or
greater than 5.2 megohm, an abnormality exists that
must be corrected before the instrument is returned
to the customer. Repeat this test with the instrument
AC switch in the off position.
d. Leakage Current Hot Check - With the instrument
completely reassembled, plug the AC line cord directly
into a 120V AC outlet. (Do not use an isolation
transformer during this test.) 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) 1410, (50.7). With the instrument
AC switch first in the on position and then in the off
Prior to shipment from the factory, our products are strictly inspected for recognized product safety and electrical
codes of the countries in which they are to be sold. However, in order to maintain such compliance, it is equally
important to implement the following precautions when a set is being serviced.
position, measure from a known earth ground (metal
water pipe, conduit, etc.) to all exposed metal parts
of the instrument (antennas, handle brackets, metal
cabinet, screw heads, metallic overlays, control
shafts, etc.), especially any exposed metal parts that
offer an electrical return path to the chassis. Any
current measured must not exceed 0.5 milli-ampere.
Reverse the instrument power cord plug in the outlet
and repeat the test.
_
DEVICE
LEAKAGE
CURRENT
TESTER
ALSO TEST WITH
PLUG REVERSED
USING AC
ADAPTER PLUG
AS REQUIRED
TEST ALL EXPOSED
METAL SURFACES
+
READING SHOULD
NOT BE ABOVE 0.5 mA
EARTH
GROUND
BEING
TESTED
ANY MEASUREMENTS NOT WITHIN THE LIMITS
SPECIFIED HEREIN INDICATE A POTENTIAL
SHOCK HAZARD THAT MUST BE ELIMINATED
BEFORE RETURNING THE INSTRUMENT TO THE
CUSTOMER OR BEFORE CONNECTING THE
ANTENNA OR ACCESSORIES.
2. Read and comply with all caution and safety-related
notes on or inside the receiver cabinet, on the receiver
chassis, or on the Liquid Crystal Panel.
3. Design Alteration Warning - Do not alter or add to
the mechanical or electrical design of this TV receiver.
Design alterations and additions, including, but not
limited to circuit modifications and the addition of
items such as auxiliary audio and/or video output
connections, might alter the safety characteristics of
this receiver and create a hazard to the user. Any
design alterations or additions will void the
manufacturer's warranty and may make you, the
servicer, responsible for personal injury or property
damage resulting therefrom.