Important Safety Notice - Panasonic PV-D4733S-K Service Manual

1. IMPORTANT SAFETY NOTICE

There are special components used in this equipment which are
important for safety. These parts are marked by
Diagrams, Circuit Board Layout, Exploded Views and Replacement
Parts List. It is essential that these criticalparts should be replaced
with manufacturer's specified parts to prevent shock, fire or other
hazards. Do not modify the original design without permission of
manufacturer.
2. An Isolation Transformer should always be used during the servicing
of DVD VCR 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 personalinjury from electrical
shocks. It will also protect DVD VCR from being damaged by
accidental shorting that may occur during servicing.
3. When servicing, observe the original lead dress. If a short circuit is
found, replace all parts which have been overheated or damaged by
the short circuit.
4. After servicing, see to it that all the protective devices such as
insulation barriers, insulation papers shields are properly installed.
5. After servicing, make the following leakage current checks to prevent
the customer from being exposed to shock hazards.
LEAKAGE CURRENT COLD CHECK
1. Unplug the AC cord and connect a jumper between the two prongs on
the plug.
2. Measure the resistance value, with an ohmmeter, between the
jumpered AC plug and each exposed metallic cabinet part on the
equipment such as screwheads, connectors, control shafts, etc. When
the exposed metallic part has a return path to thechassis, the reading
should be between 1 M
not have a return path to the chassis, the reading must be infinity.
LEAKAGE CURRENT HOT CHECK
(See figure 1.)
1. Plug the AC cord directly into the AC outlet. Do not use an isolation
transformer for this check.
2. Connect a 1.5 k
between each exposed metallic part on the set and a good earth
and 5.2 M
, 10 W resistor, in parallel with a 0.15
. When the exposed metal does
2
in the Schematic
F capacitor,