Philips BDP7100/12, Руководство по обслуживанию

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EN 4 3139 785 32970
2. Precautions
2-1 Safety Precautions
1) Before returning an instrument to the customer,
always make a safety check of the entire
instrument, including, but not limited to, the
following items:
(1) Be sure that no built-in protective devices are
defective or have been defeated during servicing.
(1) Protective shields are provided to protect both
the technician and the customer. Correctly replace
all missing protective shields, including any
removed for servicing convenience.
(2) When reinstalling the chassis and/or other
assembly in the cabinet, be sure to put back in
place all protective devices, including, but not
limited to, nonmetallic control knobs, insulating
fish papers, adjustment and compartment covers/
shields, and isolation resistor/capacitor networks.
Do not operate this instrument or permit it to be
operated without all protective devices correctly
installed and functioning.
(2) Be sure that there are no cabinet openings
through which adults or children might be able
to insert their fingers and contact a hazardous
voltage. Such openings include, but are not limited
to, excessively wide cabinet ventilation slots, and
an improperly fitted and/or incorrectly secured
cabinet back cover.
(3) Leakage Current Hot Check-With the
instrument completely reassembled, plug the
AC line cord directly into a 230V(220V ~ 240V)
AC outlet. (Do not use an isolation transformer
during this test.) Use a leakage current tester
or a metering system that complies with
American National Standardsp institute (ANSI)
C101.1 Leakage Current for Appliances and
Underwriters Laboratories (UL) 1270 (40.7). With
the instrument’s AC switch first in the ON position
and then in the OFF position, measure from a
known earth ground (metal water pipe, conduit,
etc.) to all exposed metal parts of the instrument
(antennas, handle brackets, metal cabinets,
screwheads, metallic overlays, control shafts,
etc.), especially any exposed metal parts that offer
an electrical return path to the chassis. Any current
measured must not exceed 0.5mA. Reverse
the instrument power cord plug in the outlet and
repeat the test. See Fig. 1-1.
Any measurements not within the limits specified
herein indicate a potential shock hazard that must
be eliminated before returning the instrument to the
customer.
Fig. 1-1 AC Leakage Test
(4) Insulation Resistance Test Cold Check-(1) Unplug
the power supply cord and connect a jumper wire
between the two prongs of the plug.
(2) Turn on the power switch of the instrument.
(3) Measure the resistance with an ohmmeter
between the jumpered AC plug and all exposed
metallic cabinet parts on the instrument, such as
screwheads, antenna, control shafts, handle brackets,
etc. When an exposed metallic part has a return path
to the chassis, the reading should be between 1 and
5.2 megohm. When there is no return path to the
chassis, the reading must be infinite. If the reading is
not within the limits specified, there is the possibility of
a shock hazard, and the instrument must be repaired
and rechecked before it is returned to the customer.
See Fig. 1-2.
Fig. 1-2 Insulation Resistance Test
2. Precautions