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Plug the AC cord directly into the AC outlet. Do not use an isolation transformer for this check.
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Connect a 1.5kΩ, 10 watts resistor, in parallel with a 0.15μF capacitors, between each exposed metallic part on the set and a good earth ground such as a water pipe, as shown in Figure 1.
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Use an AC voltmeter, with 1000 ohms/volt or more sensitivity, to measure the potential across the resistor.
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Check each exposed metallic part, and measure the voltage at each point.
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Reverse the AC plug in the AC outlet and repeat each of the above measurements.
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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.