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Precaution
1. Precaution
To avoid possible damages or electric shocks or exposure to radiation, follow the instructions below with regard to safety,
installation, service and ESD..
1-1 Safety Precautions
1. Make sure all protective devices are properly installed 5. Warning for Engineering Changes:
including non-metallic handles and compartment covers Never make any changes or additions to the circuit
when installing or re-installing the chassis or chassis design or the internal part for this product.
assemblies. Ex: Do not add any audio or video accessory
connectors. This might cause physical damage.
2. Make sure that no gaps exist between the cabinets for Furthermore, any changes or additions to the original
children to insert their fingers in to prevent children from design/engineering will invalidate the warranty.
receiving electric shocks. Gaps mentioned above include
ventilation holes of a too great magnitude between the 6. Warning - Hot Chassis:
vaccum tube and the cabinet mask, and the improper Some TV chassis are directly connected to one end of
installation of the rear cabinet. the AC power cord for electrical reasons.
Without insulated transistors, the product can only be
Errors may occur when the resistance is below 1.0 or repaired safely when the chassis is connected to the
over 5.2 . earthed end of the AC power source.
In these cases, make sure that the device is repaired
before sending it back to the customer. To make sure the AC power cord is properly connected,
follow the instructions below. Use the voltmeter to
3. Check for Electricity Leakage (Figure 1-1) measure the voltage between the chassis and the
Warning: Do not use an insulated transistor for checking earthed ground. If the measurement is over 1.0V, unplug
the leakage. Use only those current leakage testers or the AC power cord and change the polarity before re-
mirroring systems that comply with ANSIC 101.1 and the inserting it. Measure the voltage between the chassis
Underwriter Laboratory's specifications (UL1410, 59.7). and the ground again.
7. Some TV chassis are shipped with an additional
(READING SHOULD
secondary grounding system. The secondary system is
LEAKAGE NOT BE ABOVE adjacent to the AC power line. These two grounding
DEVICE CURRENT 0.5mA)
UNDER TESTER systems are separated in the circuit using an
TEST
unbreakable/unchangeable insulation material.
TEST ALL
EXPOSED METAL
SURFACES
8. When any parts, material or wiring appear overheated or
2-WIRE CORD damaged, replace them with new regular ones
ALSO TEST WITH immediately. When any damage or overheating is
PLUG REVERSED
(USING AC ADAPTER
detected, correct this immediately and make a regular
EARTH
PLUG AS REQUIRED) GROUND check of possible errors.
Fig. 1-1 AC Leakage Test 9. Check for the original shape of the lead, especially that
of the antenna wiring, any sharp edges, the AC power
4. A high voltage is maintained within the specified limits and the high voltage power. Carefully check if the wiring
using safety parts, calibration and tolerances. When is too tight, incorrectly placed or loose. Never change the
voltage exceeds the specified limits, check each special space between the part and the printed circuit board.
part. Check the AC power cord for possible damages. Keep
the part or the lead away from any heat-emitting
materials.
Samsung Electronics 1-1
Precaution
10. Safety Indication:
Some electrical circuits or device related materials
require special attention to their safety features, which
cannot be viewed by the naked eye. If an original part is
replaced with another irregular one, the safety or
protective features will be lost even if the new one has a
higher voltage or more watts.
Critical safety parts should be bracketed with ( ! ).
Use only regular parts for replacements (in particular,
flame resistance and dielectric strength specifications).
Irregular parts or materials may cause electric shock or
fire.
11. Pay additional attention to the current leakage as the
voltage between the power board and the ballast is 220
to 440v, i.e. very high.
And also beware of possible electric shock from the
primary power source.
1-2 Samsung Electronics
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 7. Any B+ interlock should not be damaged.
should be followed by any service personnel. If the metal heat sink is not properly installed, no
connection to the AC power should be made.
2. Make sure to unplug the AC power cord from the power
source before starting any repairs. 8. Make sure the grounding lead of the tester is connected
(a) Remove or re-install parts or assemblies. to the chassis ground before connecting to the positive
(b) Disconnect the electric plug or connector, if any. lead. The ground lead of the tester should be removed
(c) Connect the test part in parallel with the electrolytic last.
capacitor.
9. Beware of risks of any current leakage coming into
3. Some parts are placed at a higher position than the contact with the high-capacity capacitor.
printed board. Insulated tubes or tapes are used for this
purpose. The internal wiring is clamped using buckles to 10. The sharp edges of the metal material may cause
avoid contact with heat emitting parts. These parts are physical damage, so ensure wearing protective gloves
installed back to their original position. during the repair.
4. After the repair, make sure to check if the screws, parts 11. Due to the nature of plasma display panels, partial after-
or cables are properly installed. Make sure no damage is images may appear if a still picture is displayed on the
caused to the repaired part and its surroundings. screen for a long period of time.
This is caused by brightness deterioration due to the
5. Check for insulation between the blade of the AC plug storage effect of the panel, and to prevent this from
and that of any conductive materials (i.e. the metal happening, we recommend that the brightness and con-
panel, input terminal, earphone jack, etc). trast are reduced.
(e.g.) Contrast: 25, Brightness: 50
6. Insulation Check Process: Unplug the power cord from
the AC source and turn the switch on. Connect the insu- 12. A plasma panel is a device which consists of a set of
lating resistance meter (500v) to the AC plug blade. clustered pixels (cells).
A plasma panel is approved if over 99.9% of the
The insulating resistance between the blade of the AC components satisfy the necessary conditions. A few cells
plug and that of the conductive material should be more may stay illuminated or may be always off, but you do
than 1 . not have to worry as this is an approved panel and well
within the standard.
Samsung Electronics 1-3
Precaution
1-3 Static Electricity Precautions
1. Some semi-conductive ("solid state") devices are 6. Use only anti-static solder removal devices.
vulnerable to static electricity. These devices are known Most solder removal devices do not support an
as ESD. ESD includes the integrated circuit and the field anti-static feature. A solder removal device without an
effect transistor. To avoid any materials damage from anti-static feature can store enough static electricity to
electrostatic shock, follow the instructions described cause damage to the ESD.
below.
7. Do not remove the ESD from the protective box until the
2. Remove any static electricity from your body by replacement is ready. Most ESD replacements are
connecting the earth ground before handling any covered with lead, which will cause a short to the entire
semi-conductive parts or ass'ys. Alternatively, wear a unit due to the conductive foam, aluminum foil or other
dischargeable wrist-belt. conductive materials.
(Make sure to remove any static electricity before
connecting the power source - this is a safety instruction 8. Remove the protective material from the ESD
for avoiding electric shock) replacement lead immediately after connecting it to the
chassis or circuit ass'y.
3. Remove the ESD ass'y and place it on a conductive
surface such as aluminum foil to prevent accumulating 9. Take extreme caution in handling any uncovered ESD
static electricity. replacements. Actions such as brushing clothes or lifting
your leg from the carpet floor can generate enough static
4. Do not use any Freon-based chemicals. electricity to damage the ESD.
Such chemicals will generate static electricity that
causes damage to the ESD.
5. Use only grounded-tip irons for soldering purposes.
CAUTION
These servicing instructions are for use by
qualified service personnel only.
To reduce the risk of electric shock do not
perform any servicing other than that contained in the
operating instructions unless you are qualified to do so.
1-4 Samsung Electronics
Precaution
1-4 Installation Precautions
1. For safety reasons, more than two people are required 6. Keep the antenna far away from any high-voltage cables
for carrying the product. and install it firmly. Contacting the high-voltage cable or
the antenna falling over may cause fire or electric shock.
2. Keep the power cord away from any heat emitting
devices, as a melted covering may cause fire or electric 7. When connecting the RF antenna, check for a DTV
shock. receiving system and install a separate DTV reception
antenna for areas with no DTV signal.
3. Do not place the product in areas with poor ventilation
such as a bookshelf or closet. The increased internal 8. When installing the product, leave enough space (10cm)
temperature may cause fire. between the product and the wall for ventilation
purposes.
4. Bend the external antenna cable when connecting it to A rise in temperature within the product may cause fire.
the product. This is a measure to protect it from being
exposed to moisture. Otherwise, it may cause a fire or
electric shock. 9. When moving a PDP with attached speakers, detach the
speakers first before moving the main body.
5. Make sure to turn the power off and unplug the power Moving the PDP main body without separating the
cord from the outlet before removing the product. Also speakers may cause the speakers to detach, possibly
check the antenna cable or the external connectors if causing damage or injury.
they are fully unplugged. Damage to the cord may cause
fire or electric shock.
Samsung Electronics 1-5
MEMO
1-6 Samsung Electronics