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megohm and 5.2 megohms. When the exposed metal does not have a return path to the
chassis, the reading must be infinity. Remove the jumper from the ac line cord.
LEAKAGE CURRENT HOT CHECK
1. Do not use an isolation transformer for this test. Plug the completely reassembled
receiver directly into the ac outlet.
2. Connect a 1.5k, 1OW resistor paralleled by a 0.15uF. capacitor between each
exposed metallic cabinet part and a good earth ground such as a water pipe, as shown
below.
3. Use an ac voltmeter with at least 5000 ohms/volt sensitivity to measure the potential
across the resistor.
4.
The potential at any point should not exceed 0.75
volts. A leakage current tester may
be used to make this test; leakage current must not exceed 0.5milliamp. If a
measurement is outside of the specified limits, there is a possibility of shock hazard. The
receiver should be repaired and rechecked before returning it to the customer.
5. Repeat the above procedure with the ac plug reversed. (Note: An ac adapter is
necessary when a polarized plug is used. Do not defeat the polarizing feature of the
plug.)
OR
With the instrument completely reassembled, plug the AC line cord directly into a 120V
AC outlet. (Do not use an isolation transformer during this test.) Use a leakage
current tester or a metering system that complies with American National Standards
Institute (ANSI) C101.1 Leakage Current for Appliances and Underwriters Laboratories
(UL) 1410, (50.7). With the instrument AC switch first in the on position and then
in the off position, measure from a known earth ground (metal water pipe, conduit,
etc.) to all exposed metal parts of the instrument (antennas, handle brackets, metal
cabinet, screw heads, metallic overlays, control shafts, etc.), especially any exposed
metal parts that offer an electrical return path to the chassis.
Any current
measured must not exceed 0.5 milliamp.
Reverse the instrument power cord plug in
the outlet and repeat the test. See graphic below.
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