Panasonic SB-WA520EB, Service Manual

Page: 8 / 62

1.1.2 LEAKAGE CURRENT HOT CHECK (See
Figure 1.)
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1. Plug the AC cord directly into the AC outlet. Do not use an isolation transformer for this
check.
2. Connect a 1.5k
Ω
, 10 watts resistor, in parallel with a 0.15
μ
F capacitors, between each
exposed metallic part on the set and a good earth ground such as a water pipe, as shown in
Figure 1.
3. Use an AC voltmeter, with 1000 ohms/volt 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 volts RMS. A leakage current tester
(Simpson Model 229 or equivalent) may be used to make the hot checks, leakage current must
not exceed 1/2 milliamp. In case a measurement is outsideof the limits specified, there is a
possibility of a shock hazard, and the equipment should be repaired and rechecked before it is
returned to the customer.
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