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insulation barriers, insulation papers, shield, and isolation R-C
combinations etc. are properly installed.
6. After servicing, be sure to restore the wires, leads, insulation
barriers, shields, etc.
7. After servicing, make the leakage current checks to prevent the
customer from being exposed to shock hazards.
Caution:
Use a separate Isolation Transformer for this unit when servicing.
1.2. LEAKAGE CURRENT CHECK
1. Connect AC Plug to 120 volt or 240 volt AC outlet.
Do not use the ground prong of AC Plug. (See
Do not use a isolation transformer for this check.
2. Connect a 1500 ohms, 10 watts resistor, in parallel with a 0.15
F capacitor, between each exposed metallic part on the set and a
good earth ground. (See
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 1.125 volt RMS. A
leakage current tester (Simpson Model 229 equivalent) may be
Fig. 1-2-1
Fig.
1-2-2)
Fig. 1-2-2
Fig.
1-2-1)
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