Rolsen RDV-4002/RDV-4003 DVD Service Manual
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 1.5KΩ, 10 Watts resistor, in parallel with a 0.15uF 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 (Slmpson 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 outside of limits specified, there is a possibility
of shock hazard, and the equipment should be repaired and rechecked
before it is returned to the customer.
PREVENTION OF ELECTP.O STATIC DISCHARGE (ESD) TO
ELECTROSTATICALLY SENSITIVE ( ES ) DEVICE
Some semiconductor (solid state) devices can be damaged easily by
static electricity. Such components commonly are called
Electro-statically Sensitive (ES) Device. Examples of typical ES device are integrated circuits and some field-effect transistors and
semiconductor ‘chip’ components. The following techniques should be used to help reduce the incidence of component damage caused by
