Panasonic TX-34P150X, Service Manual

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6. After servicing make the following leakage current checks to
prevent the customer from being exposed to shock hazards.
1.2. Leakage Current Cold Check
1. Unplug the AC cord and connect a jumper between the two
prongs on the plug.
2. Turn on the receiver’s power switch.
3. Measure the resistance value, with an ohmmeter, between the
jumper AC plug and each exposed metallic cabinet part on the
receiver, such as screw heads, aerials, connectors, control
shafts, etc. When the exposed metallic part has a return path to
the chassis, the reading should be between 4 M and 20 M .
When the exposed metal does not have a return path to the
chassis, the reading must be infinite.
1.3. Leakage Current Hot Check (See Fig. 1)
1. Plug the AC cord directly into the AC outlet. Do not use an
isolation transformer for this check.
2. Connect a 2k , 10 W resistor in series with an exposed metallic
part on the receiver and an earth such as a water pipe.
3. Use an AC voltmeter, with high impedance type, to measure the
potential across the resistor.
4. Check each exposed metallic part, and measure the voltage at
each point.