Panasonic SA-HT535EE, Руководство по обслуживанию

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Subwoofer Unit)
Disconnect AC power, discharge Power Supply Capacitors C2080 through a 10 , 10 W resistor
to ground.
DO NOT SHORT-CIRCUIT DIRECTLY (with a screwdriver blade, for instance), as this may
destroy solid state devices.
After repairs are completed, restore power gradually using a variac, to avoid overcurrent.
Current consumption at AC 230V, 50Hz in NO SIGNAL mode should be ~850 mA (Active
Subwoofer).
3. SAFETY PRECAUTIONS
3.1. GENERAL GUIDELINES
1. 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.
2. After servicing, ensure that all the protective devices such as
insulation barriers, insulation papers shields are properly
installed.
3. After servicing, make the following leakage current checks to
prevent the customer from being exposed to shock hazards.
3.1.1. LEAKAGE CURRENT COLD CHECK (FOR ACTIVE SUBWOOFER)
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 the chassis,
the reading should be between 1M and 5.2 . / When the
exposed metal does not have a return path to the chassis, the
reading must be .
Fig. 1
3.1.2. LEAKAGE CURRENT HOT CHECK (See Figure 1.)
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