Mitsubishi Electric DD-4020, Руководство по обслуживанию

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IMPORTANT SAFETY PRECAUTIONS
Product Safety Notice
Some electrical and mechanical parts have special
safety-related characteristics which are often not evi-
dent from visual inspection, nor can the protection they
give necessarily be obtained by replacing them with
components rated for higher voltage, wattage, etc. Parts
that have special safety characteristics are identified by
a
#
on schematics and in parts lists. Use of a substi-
tute replacement that does not have the same safety
characteristics as the recommended replacement part
might create shock, fire, and/or other hazards. The
Product’s Safety is under review continuously and new
instructions are issued whenever appropriate. Prior to
shipment from the factory, our products are carefully
inspected to confirm with the recognized product safety
and electrical codes of the countries in which they are
to be sold. However, in order to maintain such compli-
ance, it is equally important to implement the following
precautions when a set is being serviced.
Precautions during Servicing
A. Parts identified by the
#
symbol are critical for
safety. Replace only with part number specified.
B. In addition to safety, other parts and assemblies are
specified for conformance with regulations applying
to spurious radiation. These must also be replaced
only with specified replacements.
Examples: RF converters, RF cables, noise block-
ing capacitors, and noise blocking filters, etc.
C. Use specified internal wiring. Note especially:
1) Wires covered with PVC tubing
2) Double insulated wires
3) High voltage leads
D. Use specified insulating materials for hazardous live
parts. Note especially:
1) Insulation tape
2) PVC tubing
3) Spacers
4) Insulators for transistors
E. When replacing AC primary side components
(transformers, power cord, etc.), wrap ends of wires
securely about the terminals before soldering.
F. Observe that the wires do not contact heat produc-
ing parts (heatsinks, oxide metal film resistors, fus-
ible resistors, etc.).
G. Check that replaced wires do not contact sharp
edges or pointed parts.
H. When a power cord has been replaced, check that
5 - 6 kg of force in any direction will not loosen it.
I. Also check areas surrounding repaired locations.
J. Use care that foreign objects (screws, solder drop-
lets, etc.) do not remain inside the set.
K. Crimp type wire connector
The power transformer uses crimp type connectors
which connect the power cord and the primary side
of the transformer. When replacing the transformer,
follow these steps carefully and precisely to prevent
shock hazards.
Replacement procedure
1) Remove the old connector by cutting the wires at a
point close to the connector.
Important: Do not re-use a connector. (Discard it.)
2) Strip about 15 mm of the insulation from the ends of
the wires. If the wires are stranded, twist the strands
to avoid frayed conductors.
3) Align the lengths of the wires to be connected. Insert
the wires fully into the connector.
4) Use a crimping tool to crimp the metal sleeve at its
center. Be sure to crimp fully to the complete closure
of the tool.
L. When connecting or disconnecting the internal con-
nectors, first, disconnect the AC plug from the AC
outlet.
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