Samsung HPR4272CX/XAC, Service Manual

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1. The service instructions are printed on the cabinet, and
should be followed by any service personnel.
2. Make sure to unplug the AC power cord from the power
source before starting any repairs.
(a) Remove or re-install parts or assemblies.
(b) Disconnect the electric plug or connector, if any.
(c) Connect the test part in parallel with the electrolytic
capacitor.
3. Some parts are placed at a higher position than the
printed board. Insulated tubes or tapes are used for this
purpose. The internal wiring is clamped using buckles to
avoid contact with heat emitting parts. These parts are
installed back to their original position.
4. After the repair, make sure to check if the screws, parts
or cables are properly installed. Make sure no damage is
caused to the repaired part and its surroundings.
5. Check for insulation between the blade of the AC plug
and that of any conductive materials (i.e. the metal
panel, input terminal, earphone jack, etc).
6. Insulation Check Process: Unplug the power cord from
the AC source and turn the switch on. Connect the insu-
lating resistance meter (500v) to the AC plug blade.
The insulating resistance between the blade of the AC
plug and that of the conductive material should be more
than 1
㏁
.
7. Any B+ interlock should not be damaged.
If the metal heat sink is not properly installed, no
connection to the AC power should be made.
8. Make sure the grounding lead of the tester is connected
to the chassis ground before connecting to the positive
lead. The ground lead of the tester should be removed
last.
9. Beware of risks of any current leakage coming into
contact with the high-capacity capacitor.
10. The sharp edges of the metal material may cause
physical damage, so ensure wearing protective gloves
during the repair.
11. Due to the nature of plasma display panels, partial after-
images may appear if a still picture is displayed on the
screen for a long period of time.
This is caused by brightness deterioration due to the
storage effect of the panel, and to prevent this from
happening, we recommend that the brightness and con-
trast are reduced.
(e.g.) Contrast: 25, Brightness: 50
Precaution
Samsung Electronics 1-3
Warning 1: First carefully read the "Safety Instruction" in this service manual.
When there is a conflict between the service and the safety instructions, follow the safety instruction at all times.
Warning 2: Any electrolytic capacitor with the wrong polarity will explode.
1-2 Servicing Precautions