Sharp LC-13E2U Service Manual - Page 2

LC-13E2U LC-15E2U/20E2U IMPORTANT SERVICE SAFETY PRECAUTION Ë Service work should be perfomed only by qualified service technicians who are thoroughly familiar with all safety checks and the servicing guidelines which follow: WARNING 1. For continued safety, no modification of any circuit should be attempted. 2. Disconnect AC power before servicing. LC-13/15E2U A V CAUTION: FOR CONTINUED PROTECTION AGAINST A RISK OF FIRE REPLACE ONLY WITH SAME TYPE F3701 (2.0A, 125V), F6500 (1.6A, 125V) AND F6501 (1.6A, 125V) FUSE. LC-20E2U A V CAUTION: FOR CONTINUED PROTECTION AGAINST A RISK OF FIRE REPLACE ONLY WITH SAME TYPE F3701 (2.0A, 125V), F3702 (1.6A, 125V), F6700 (1.0A, 125V), F6701 (1.0A, 125V), F6702 (1.0A, 125V), F6703 (1.0A, 125V) AND F6704 (1.0A, 125V) FUSE. BEFORE RETURNING THE RECEIVER (Fire & Shock Hazard) Before returning the receiver to the user, perform the following safety checks: • Plug the AC cord directly into a 110~240 volt AC outlet, and connect the DC power cable into the receiver's DC jack. (Do not use an isolation transformer for this test). • Using two clip leads, connect a 1.5k ohm, 10 watt resistor paralleled by a 0.15µF capacitor in series with all exposed metal cabinet parts and a known earth ground, such as electrical conduit or electrical ground connected to an earth ground. • Use an AC voltmeter having with 5000 ohm per volt, or higher, sensitivity or measure the AC voltage drop across the resisor. • Connect the resistor connection to all exposed metal parts having a return to the chassis (antenna, metal cabinet, screw heads, knobs and control shafts, escutcheon, etc.) and measure the AC voltage drop across the resistor. All checks must be repeated with the AC cord plug connection reversed. (If necessary, a nonpolarized adaptor plug must be used only for the purpose of completing these checks.) Any reading of 0.75V peak (this corresponds to 0.5 milliamp. peak AC.) or more is excessive and indicates a potential shock hazard which must be corrected before returning the monitor to the owner. 1. Inspect all lead dress to make certain that leads are not pinched, and check that hardware is not lodged between the chassis and other metal parts in the receiver. 2. Inspect all protective devices such as non-metallic control knobs, insulation materials, cabinet backs, adjustment and compartment covers or shields, isolation resistor-capacitor networks, mechanical insulators, etc. 3. To be sure that no shock hazard exists, check for leakage current in the following manner. DVM AC SCALE 1.5k ohm 10W 0.15 µF TEST PROBE TO EXPOSED CONNECT TO METAL PARTS KNOWN EARTH 111222333444555666777888999000111222333444555666777888999000111222333444555666777888999000111222111222333444555666777888999000111222333444555666777888999000111222333444555666777888999000111222111222333444555666777888999000111222333444555666GR777O888U999N000D111222333444555666777888999000111222111222 SAFETY NOTICE Many electrical and mechanical parts in LCD television and shaded areas in the Replacement Parts Lists and have special safety-related characteristics. Schematic Diagrams. These characteristics are often not evident from visual For continued protection, replacement parts must be inspection, nor can protection afforded by them be identical to those used in the original circuit. necessarily increased by using replacement components The use of a substitute replacement parts which do not rated for higher voltage, wattage, etc. have the same safety characteristics as the factory Replacement parts which have these special safety recommended replacement parts shown in this service characteristics are identified in this manual; electrical manual, may create shock, fire or other hazards. components having such features are identified by " å" 111222333444555666777888999000111222333444555666777888999000111222333444555666777888999000111222111222333444555666777888999000111222333444555666777888999000111222333444555666777888999000111222111222333444555666777888999000111222333444555666777888999000111222333444555666777888999000111222111222 2