Beko P7, Service Manual

Page: 3 / 129

SAFETY PRECAUTIONS
GENERAL GUIDELINES
1.
It is advised to insert an isolation transformer in the
AC supply before servicing a hot chassis.
2.
Always use the manufacturer’s replacement safety
components. The critical safety components marked
with on the schematics diagrams should not be
by other substitutes. Other substitute may create the
electrical shock , fire or other hazards. Take
attention to replace the spacers with the originals.
Furthermore where a short circuit has occurred ,
replace those components that indicate evidence of
overheating.
3.
After servicing , see that all the protective devices
such as insulation barriers, insulation papers, shields
and isolation R-C combinations are correctly
installed.
4.
When the receiver is not being used for a long time
of period of time , unplug the power cord of the
Adaptor from the AC outlet.
PDP Module is very sensitive
both electrically and physically.Users,
therefore, are requested to follow the
“Guidance of handling color
PDP
Module”on the followings.
1 -
Be careful not to make scratch on the
polarizer.
Surface of polarizer is soft and can be physically
damaged easily.Please do not touch, push or rub
polarizer surface with materials over HB hardness.
2 - Keep clean the surface.
Please wear rubber glove when touch the surface of
PDP
screen. Please use soft and anti-static material
as cleaner.
3 -Keep out of water. Water on/in the
PDP
may
cause electrical short or corrosion. Please wipe out
dry or water carefully
.
4 -Prevent swift Temperature & Humidity
change. Instantaneous temperature and/or humidity
change can make dew or ice which cause
nonconformance such as malfunction.
5 - High temperature & high humidity
reduce the life-time.
PDP
is not proper to be used at high temperature
and high humidity. Please keep specified
temperature and humidity condition.
6 - Keep out of Corrosive Gas. Corrosive gas
effect the polarizer and the circuit chemically and
cause defects accordingly.
7 - Electrostatic discharge can make
Damage
There are electro-static sensitive components
in
PDP
Module. Please earth human
body when handle the
PDP
.In addition, please do
not touch the interface connector pin with bare.
8 - Do not operate for a long time under
the same pattern
Operating
PDP
for a long time under the same
pattern can cause image persistence and can
damage it. Please follow following guidance.
1. Turn the power off when do not use.
2. Change the pattern periodically.
LEAKAGE CURRENT COLD CHECK
1.
Unplug the AC cord and connect a jumper
between the two prongs of the plug.
2.
Turn the receiver’s power switch.
3.
Measure the resistance value with an ohmmeter,
between the jumpered AC plug and each exposed
metallic cabinet part on the receiver. When the exposed
metallic part a return path to the chassis the reading
should be between 4Mohm and the 20Mohm. When the
exposed metal does not have a return path to the chassis,
the reading must be infinite.
LEAKAGE CURRENT HOT CHECK
1.
Plug the AC cord directly in to the AC outlet. Do
not use an isolation transformer for this check.
2.
Connect a 2Kohm 10W resistor in series with an
exposed metallic part on the receiver and an earth,
such as a water pipe.
3.
Use an AC voltmeter with high impedance to
measure the potential across the resistor.
4.
Check each exposed metallic part and check the
voltage at the each point.
5.
Reverse the AC plug at the outlet and repeat each of
the above measurements.
6.
The potential at the any point should not exceed 1.4
Vrms. In case a measurement is outside the limits
specified , there is the possibility of a shock hazard ,
and the receiver should be repaired and rechecked
before it is returned to the customer.
HOT CHECK CIRCUIT
AC-Voltmeter
TO INSTRUMENTS
EXPOSED
METALLIC PARTS
Water pipe
(earth)
2 K Ohm