Hitachi 32PD3000E, Service Manual

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32PD3000 / 42PD3000
1
Safety
ENGLISH
SAFETY PRECAUTIONS
WARNING:
The following precautions must be
observed.
ALL PRODUCTS
Before any service is performed on the chassis an
isolation transformer should be inserted between
the power line and the product.
1. When replacing the chassis in the cabinet,
ensure all the protective devices are put back in
place.
2. When service is required, observe the original
lead dressing. Extra precaution should be taken to
ensure correct lead dressing in any high voltage
circuitry area.
3. Many electrical and mechanical parts in
HITACHI products have special safety related
characteristics. These characteristics are often not
evident from visual inspection, nor can the
protection afforded by them necessarily be
obtained by using replacement components rated
for higher voltage, wattage, etc. Replacement parts
which have these special safety characteristics are
identified by marking with a ! on the schematics
and the replacement parts list. The use of a
substitute replacement component that does not
have the same safety characteristics as the
HITACHI recommended replacement one, shown
in the parts list, may create electrical shock, fire, X-
radiation, or other hazards.
4. Always replace original spacers and maintain
lead lengths. Furthermore, where a short circuit has
occurred, replace those components that indicate
evidence of overheating.
5. Insulation resistance should not be less than 2M
ohms at 500V DC between the main poles and any
accessible metal parts.
6. No flashover or breakdown should occur during
the dielectric strength test, applying 3kV AC or
4.25kV DC for two seconds between the main
poles and accessible metal parts.
7. Before returning a serviced product to the
customer, the service technician must thoroughly
test the unit to be certain that it is completely safe
to operate without danger of electrical shock. The
service technician must make sure that no
protective device built into the instrument by the
manufacturer has become defective, or
inadvertently damaged during servicing.
CE MARK
1. HITACHI products may contain the CE mark on
the rating plate indicating that the product contains
parts that have been specifically approved to
provide electromagnetic compatibility to designated
levels.
2. When replacing any part in this product, please
use only the correct part itemised in the parts list to
ensure this standard is maintained, and take care
to replace lead dressing to its original state, as this
can have a bearing on the electromagnetic
radiation/immunity.
PICTURE TUBE
1. The line output stage can develop voltages in
excess of 25kV; if the E.H.T. cap is required to be
removed, discharge the anode to chassis via a high
value resistor, prior to its removal from the picture
tube.
2. High voltage should always be kept at the rated
value of the chassis and no higher. Operating at
higher voltages may cause a failure of the picture
tube or high voltage supply, and also, under certain
circumstances could produce X-radiation levels
moderately in excess of design levels. The high
voltage must not, under any circumstances, exceed
29kV on the chassis (except for projection
Televisions).
3. The primary source of X-radiation in the product
is the picture tube. The picture tube utilised for the
above mentioned function in this chassis is
specially constructed to limit X-radiation. For
continued X-radiation protection, replace tube with
the same type as the original HITACHI approved
type
4. Keep the picture tube away from the body while
handling. Do not install, remove, or handle the
picture tube in any manner unless shatterproof
goggles are worn. People not so equipped should
be kept away while picture tubes are handled
LASERS
If the product contains a laser avoid direct
exposure to the beam when the cover is open or
when interlocks are defeated or have failed.