Figure1
LEAKAGE CURRENT HOT CHECK (See Figure 1)
1. Plug the AC cord directly into the AC 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 on the set an a
good earth ground such as a water pipe, as shown in Figure1.
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. Reverses the AC plug in the AC outlet repeat each of the above
measurements.
6. The potential at any point should not exceed 0.15 volts RMS. A
leakage current tester (Simpson Model 229 equivalent) may be
used to make the hot checks, leakage current must not exceed 0.1
milliamp. In case a measurement is outside of the limits specified,
there is a possibility of a shock hazard, and the equipment should
be repaired and checked before it is returned to the customer.
ABOUT LEAD FREE SOLDER (PbF)
Distinction of Pbf PCB:
PCBs (manufactured) using lead free solder will have a PbF stamp on the PCB.
Caution:
1. Pb free solder has a higher melting point than standard solder;
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