LG 50PC1DR - - 50" Plasma TV Training Manual Download

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Plasma Training

Overview

SAFETY

Protect the power cord from physical or mechanical abuse, such as being twisted, kinked, pinched,
closed in a door, or walked upon. Pay particular attention to plugs, wall outlets, and the point where
the cord exits the appliance.

ELECTRICAL SAFETY NOTICE

Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified
in the Schematic Diagram and Replacement Parts List. It is essential that these special safety parts should be replaced
with the same components as recommended in this manual to prevent , Shock, Fire, or other Hazards. Do not modify the
original design without permission of manufacturer.

ELECTRICAL SHOCK WARNING

An lsolation Transformer should always be used during the servicing of a receiver whose chassis is not isolated from the
AC power line. Use a transformer of adequate power rating as this protects the technician from accidents resulting in
personal injury from electrical shocks. It will also protect the receiver and its components from being damaged by
accidental shorts of the circuit that may be inadvertently introduced during the service operation. If any fuse (or
Fusible Resistor) in this monitor is blown, replace it with the same specified type. When replacing a high wattage
resistor (Oxide Metal Film Resistor, over 1W), keep the resistor 10mm away from PCB. Keep wires away from high voltage
or high temperature parts.

LEAKAGE CURRENT COLD CHECK (ANTENNA COLD CHECK)

With the instrument AC plug removed from AC source, connect an electrical jumper across the two AC plug prongs.
Place the AC switch in the on positioin, connect one lead of ohm-meter to the AC plug prongs tied together and
touch other ohm-meter lead in turn to each exposed metallic parts such as antenna terminals, phone jacks, etc. If
the exposed metallic part has a return path to the chassis, the measured resistance should be between 1M ohm and
5.2M ohm. When the exposed metal has no return path to the chassis the reading must be infinite. An other
abnormality exists that must be corrected before the receiver is returned to the customer.

LEAKAGE CURRENT HOT CHECK

Plug the AC cord directly into the AC outlet. Do not use a line Isolation Transformer during this check. Connect
1.5K/10watt resistor in parallel with a 0.15uF capacitor between a known good earth ground (Water Pipe, Conduit,
etc.) and the exposed metallic parts. Measure the AC voltage across the resistor using AC voltmeter with 1000 ohms/
volt or more sensitivity. Reverse plug the AC cord into the AC outlet and repeat AC voltage measurements for each
exposed metallic part. Any voltage measured must not exceed 0.75 volt RMS which corresponds to 0.5mA. In case
any measurement is out of the limits sepcified, there is possibility of shock hazard and the set must be checked and
repaired before it is returned to the customer.

LEAKAGE CURRENT HOT CHECK CIRCUIT

Good Earth

Ground

Exposed

Metallic Parts

Volt Meter

0.15uF

1.5Kohm/10W