Samsung LE15S51BP, Service Manual

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1 Precautions
1-1
1-1-1 Warnings
1. For continued safety, do not attempt to modify the
circuit board.
2. Disconnect the AC power and DC Power Jack before
servicing.
1-1-2 Servicing the LCD Monitor
1. When servicing the LCD Monitor Disconnect the AC
line cord from the AC outlet.
2. It is essential that service technicians have an accurate
voltage meter available at all times. Check the
calibration of this meter periodically.
1-1-3 Fire and Shock Hazard
Before returning the monitor to the user, perform the
following safety checks:
1. Inspect each lead dress to make certain that the leads
are not pinched or that hardware is not lodged between
the chassis and other metal parts in the monitor.
2. Inspect all protective devices such as nonmetallic
control knobs, insulating materials, cabinet backs,
adjustment and compartment covers or shields,
isolation resistor-capacitor networks, mechanical
insulators, etc.
3. Leakage Current Hot Check (Figure 1-1):
WARNING: Do not use an isolation
transformer during
this test.
Use a leakage current tester or a metering system that
complies with American National Standards Institute
(
ANSI C101.1, Leakage Current for Appliances ), and
Underwriters Laboratories ( UL Publication UL1410,
59.7 ).
Figure 1-1. Leakage Current Test Circuit
4. With the unit completely reassembled, plug the AC
line cord directly into a 120V AC outlet. With the
unit’s AC switch first in the ON position and then
OFF, measure the current between a known earth
ground (metal water pipe, conduit, etc.) and all
exposed metal parts, including: metal cabinets,
screwheads and control shafts. The current measured
should not exceed 0.5 milliamp. Reverse the power-
plug prongs in the AC outlet and repeat the test.
1-1-4 Product Safety Notices
Some electrical and mechanical parts have special
safety-related characteristics which are often not evident
from visual inspection. The protection they give may not
be obtained by replacing them with components rated for
higher voltage, wattage, etc. Parts that have special safety
characteristics are identified by on schematics and parts
lists. A substitute replacement that does not have the same
safety characteristics as the recommended replacement part
might create shock, fire and/or other hazards. Product
safety is under review continuously and new instructions
are issued whenever appropriate.
1 Precautions
Follow these safety, servicing and ESD precautions to prevent damage and to protect against potential hazards such as electrical shock.
1-1 Safety Precautions