Emerson EWL20S5, Service Manual

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2-3 LTVN_ISP
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
blocking 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
producing parts (heat sinks, oxide metal film
resistors, fusible resistors, etc.)
G. Check that replaced wires do not contact sharp
edged 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
droplets, 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 the crimping tool to crimp the metal sleeve
at the center position. Be sure to crimp fully to
the complete closure of the tool.
L. When connecting or disconnecting the internal
connectors, first, disconnect the AC plug from the
AC supply outlet.
M. When installing parts or assembling the cabinet
parts, be sure to use the proper screws and
tighten certainly.