Samsung PN50C450B1DXZC, Service Manual

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Samsung Electronics 1-3
Precaution
1-2 Servicing Precautions
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. 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 insulating 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 1MΩ.
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 protect yourself by wearing 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 contrast are reduced.
(e.g.) Contrast: 25, Brightness: 50