Panasonic CT 30WX52, Service Manual

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the AC plug with a jumper wire.
2. Set the power switch of this set to ON position.
3. Measure the resistance value with an ohmmeter between the
shorted AC plug and each exposed metallic part of the set cabinet
such as screwheads, connectors, and control shafts. When the
exposed metallic part has a return path to the chassis,the reading
should be more than 1 M . / When the exposed metal part does
not have a return path to the chassis, the reading must be infinity.
1.3. Leakage Current Hot Check (See Fig.1)
1. Plug the AC power cord directly into the AC line outlet. Do not use
an isolation transformer for this check.
2. Connect a 1.5k , 10W resistor, in parallel with a 0.15 F capacitor
between each exposed metallic part of the set and an earth ground
such as a water pipe.
3. Use a high impedance AC voltage meter to measure the voltage
across the resistor.
4. Measure the voltage at each exposed metallic part.
5. Reverse the AC plug inserting direction at the AC line outlet and
repeat each of the above measurements.
6. The voltage at any point must be less than 0.75Vrms.
7. A leakage current tester (Symptom Model 229 or the equivalent)
may be used to make the hot checks. In this case, the current
must be less than 500 A.
8. If the reading is more than the above value, the set must be
repaired and rechecked before it is returned to the customer
because of a possibility of an electrical shock.
Fig. 1
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