Panasonic PV 20DF62, Руководство по обслуживанию

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1. Unplug the AC cord and connect a jumper between the two
prongs on the plug.
2. For physically operated power switches, turn power on.
Otherwise skip step 2.
3. Measure the resistance value, with an ohmmeter, between the
jumpered AC plug and each exposed metallic cabinet part on the
receiver, such as screwheads, connectors, etc. When the
exposed metallic part has a return path to the chassis, the
reading should be between 1 M and 12 M . When the exposed
metal does not have a return path to the chassis, the reading
must be infinity.
1.3. LEAKAGE CURRENT HOT CHECK
1. Plug the AC cord directly into the AC outlet.
Do not use a isolation transformer for this check.
2. Connect a 1.5 k , 10 W resistor, in parallel with a 0.15 F
capacitor, between each exposed metallic part on the set and a
good earth ground, as shown in Figure 1.
3. Use an AC voltmeter, with 1 k /V or more sensitivity, to measure
the potential across the resistor.
4. Check each exposed metallic part, and measure the voltage at
each point.
5. Reverse the AC plug in the AC outlet and repeat each of the above
measurements.
6. The potential at any point should not exceed 0.75 V RMS.
A leakage current tester (Simpson Model 229 equivalent) may be
used to make the hot checks. Leakage current must not exceed 1/
2 mA. In case a measurement is outside of the limits specified,
there is a possibility of shock hazard, and the receiver should be
repaired and rechecked before it is returned to the customer.
Figure 1