LG 55LB6500, Руководство по обслуживанию

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SAFETY PRECAUTIONS
IMPORTANT SAFETY
NOTICE
Many
electrical
and mechanical
parts in this
chassis
have
special safetyrelated
characteristics
These
parts
are
identified
by
b
in
the
Schematic
Diagram
and
Exploded
View
It
is
essential that these
special safety parts
should
be
replaced
with the
same
components
as recommended
in this
manual
to prevent
Shock
Fire or other
Hazards
Do
not
modify
the
original
design
without
permission
of manufacturer
General
Guidance
An
isolation
Transformer should
always
be used
during
the
servicing
of a receiver
whose
chassis
is
not isolated from the
AC
power line
Use
a transformer of adequate power
rating
as
this
protects
the technician from accidents
resulting in personal
injury
from
electrical
shocks
It
will
also
protect
the receiver
and
its
components
from
being
damaged
by
accidental shorts
of
the
circuitry
that
may
be
inadvertently
introduced
during
the service
operation
If
any
fuse or
Fusible Resistor
in
this
TV
receiver
is
blown
replace it
with the
specified
When
replacing
a
high
wattage
resistor
Oxide
Metal Film
Resistor
over
1
W
keep
the resistor
10
mm
away
from
PCB
Keep
wires
away
from
high voltage
or
high
temperature
parts
Before
returning
the receiver to the customer
always perform an
AC
leakage
current check on
the exposed
metallic
parts
of the
cabinet
such
as antennas
terminals
etc
to
be
sure
the
set is
safe
to operate
without damage of electrical
shock
Leakage Current
Cold CheckAntenna
Cold
Check
With
the instrument
AC
plug
removed
from
AC
source
connect an
electrical jumper
across
the
two
AC
plug prongs
Place
the
AC
switch
in
the
on
position
connect
one
lead of
ohm
meter
to the
AC
plug
prongs
tied
together
and
touch other
ohmmeter
lead
in
turn to
each
exposed
metallic
parts
such
as antenna terminals
phone
jacks
etc
If
the
exposed
metallic
part
has
a return
path
to
the
chassis
the
measured
resistance should
be between
1
MO
and
52
MO
When
the
exposed
metal
has no
return
path
to
the chassis the
reading
must be
infinite
An
other abnormality exists that
must be
corrected before the
receiver
is
returned
to
the
customer
Leakage Current
Hot Check See
below
Figure
Plug
the
AC
cord
directly
into
the
AC
outlet
Do
not use a
line Isolation
Transformer
during this
check
Connect
15 K
10
watt resistor
in
parallel
with a
015
uF
capacitor
between
a
known
good
earth
ground
Water
Pipe Conduit
etc
and
the
exposed
metallic
parts
Measure
the
AC
voltage
across
the resistor
using
AC
voltmeter
with
1000 ohmsvolt
or
more
sensitivity
Reverse
plug
the
AC
cord
into
the
AC
outlet
and
repeat
AC
voltage
measurements
for
each
exposed
metallic
part
Any
voltage
measured must
not
exceed
075
volt
RMS
which
is corresponds to
05
mA
In
case
any
measurement
is
out of the
limits specified
there
is
possibility
of
shock hazard and
the set
must be checked and
repaired
before
it
is
returned
to
the
customer
Leakage
Current
Hot Check
circuit
AC
Voltmeter
To Instruments
exposed
METALLIC PARTS
Good
Earth
Grcund
such
as
WATER
PIPE
CONDUIT etc
When
25A
is
impressed
between
Earth
and 2nd Ground
for
1
second
Resistance
must
be
less
than
01
0
xBase
on Adjustment
standard
Copyright
n
2014
LG
Electronics Inc
All
rights
reserved
Only for training
and
service
purposes
Confidential
Business
Information
Subject
to Protective
Order
3
LGE
Internal
Use
Only
LGE910IT000143506
CX13790003