Panasonic VDR-M95PP Service Manual

Also see for VDR-M75PP: Operating instructions Operating instructions

Contents

Panasonic VDR-M95PP Service Manual Manual pdf 3 page image

1 Safety PrecautionsGENERAL GUIDELINES1. IMPORTANT SAFETY NOTICEThere are special components used in this equipmentwhich are important for safety. These parts are marked byin the Schematic Diagrams, Circuit Board Layout,Exploded Views and Replacement Parts List. It isessentialthat these critical parts should be replaced withmanufacturer’s specified parts to prevent shock, fire, orother hazards. Do not modify the original design withoutpermission of manufacturer.2. An Isolation Transformer should always be used during theservicing of AC Adaptor whose chassis is not isolated fromthe AC power line. Use a transformer of adequate powerrating as this protects the technician from accidentsresulting in personalinjury from electrical shocks. It will alsoprotect AC Adaptor from being damaged by accidentalshorting that may occur during servicing.3. When servicing, observe the original lead dress. If a shortcircuit is found, replace all parts which have beenoverheated or damaged by the short circuit.4. After servicing, see to it that all the protective devices suchas insulation barriers, insulation papers shields are properlyinstalled.5. After servicing, make the following leakage current checksto prevent the customer from being exposed to shockhazards.LEAKAGE CURRENT COLD CHECK1. Unplug the AC cord and connect a jumper between the twoprongs on the plug.2. Measure the resistance value, with an ohmmeter, betweenthe jumpered AC plug and each exposed metallic cabinetpart on the equipment such as screwheads, connectors,control shafts, etc. When the exposed metallic part has areturn path to thechassis, the reading should be between 1MΩ and 5.2 MΩ. When the exposed metal does not have areturn path to the chassis, the reading must be infinity.LEAKAGE CURRENT HOT CHECK(See Figure 1.)1. Plug the AC cord directly into the AC outlet. Do not use anisolation transformer for this check.2. Connect a 1.5 kΩ, 10 W resistor, in parallel with a 0.15 μFcapacitor, between each exposed metallic part on the setand a good earth ground, as shown in Figure 1.3. Use an AC voltmeter, with 1 kΩ/V or more sensitivity, tomeasure the potential across the resistor.4. Check each exposed metallic part, and measure thevoltage at each point.5. Reverse the AC plug in the AC outlet and repeat each of theabove measurements.6. The potential at any point should not exceed 0.75 V RMS.A leakage current tester (Simpson Model 229 or equivalent)may be used to make the hot checks, leakage current mustnot exceed 1/2 mA. In case a measurement is outside ofthelimits specified, there is a possibility of a shock hazard,and the equipment should be repaired and recheckedbefore it is returned to the customer.Figure. 13VDR-M95PP / VDR-M75PP / VDR-M55PP / VDR-M53PP