Panasonic TX-32LX60M Service Manual

Panasonic TX-32LX60M Service Manual Manual pdf 4 page image

3. After servicing, make the following leakage current checks toprevent the customer from being exposed to shock hazards.1.1.1. Leakage Current Cold Check1. Unplug the AC cord and connect a jumper between the twoprongs on the plug.2. Measure the resistance value, with an ohmmeter, between thejumpered AC plug and each exposed metallic cabinet part on theequipment 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 5.2M .When the exposed metal does not have a return path to thechassis, the reading must be .Figure 11.1.2. LEAKAGE CURRENT HOT CHECK (See Figure 1.)1. Plug the AC cord directly into the AC outlet. Do not use anisolation transformer for this check.2. Connect a 1.5k , 10 watts resistor, in parallel with a 0.15 Fcapacitors, between each exposed metallic part on the set and agood earth ground such as a water pipe, as shown in Figure 1.3. Use an AC voltmeter, with 1000 ohms/volt or more sensitivity, tomeasure the potential across the resistor.4. Check each exposed metallic part, and measure the voltage ateach point.5. Reverse the AC plug in the AC outlet and repeat each of the abovemeasurements.6. The potential at any point should not exceed 0.75 volts RMS. Aleakage current tester (Simpson Model 229 or equivalent) may beused to make the hot checks, leakage current must not exceed 1/24