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MICROWAVE OVEN
SERVICE MANUAL
MODEL: MV1526W
MV1526B
CAUTION
BEFORE SERVICING THE UNIT, READ THE
SAFETY PRECAUTIONS IN THIS MANUAL.
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CAUTION SAFETY PRECAUTIONS PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICING TO AVOID POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY a. Do not operate or allow the oven to be operated with the door open. b. Make the following safety checks on all ovens to be serviced before activating the magnetron or other microwave source, and make repairs as necessary; (1) Interlock operation, (2) proper door closing, (3) seal and sealing surfaces (arcing, wear, and other damage), (4) damage to or loose
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FOREWORD Read this Manual carefully. Failure to adhere to or observe the information in this Manual may result in exposing yourself to the Microwave Energy normally contained within the oven cavity. TABLE OF CONTENTS (Page) SAFETY PRECAUTIONS ......................................................................................................... Inside front page SPECIFICATIONS.....................................................................................................................
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SPECIFICATIONS Rated Power Consumption..................................................1,500W maximum (Microwave oven+Cook top lamps+Ventilation fan) Microwave Output.................................................................1,000W (IEC 60705) Adjustable 100W through 1000W, 10 steps Frequency.............................................................................2,450 MHz ± 50 MHz Power Supply........................................................................120 VAC, 60 Hz Rate
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CAUTIONS Unlike other appliances, the microwave oven is MICROWAVE RADIATION high-voltage and high-current equipment. Personnel should not be exposed to the Though it is free from danger in ordinary use, microwave energy which may radiate from the extreme care should be taken during repair. magnetron or other microwave generating device if it is improperly used or connection. • DO NOT operate on a 2-wire extension cord during All input and output microwave connections, repair and use. waveguide,
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INSTALLATION BEFORE YOU BEGIN, READ THE FOLLOWING INSTRUCTIONS COMPLETELY AND CAREFULLY. PRECAUTIONS ON INSTALLATION A. Plug the power supply cord into a 120V AC, 60Hz, single-phase power source with a capacity of 15A or 20A. B. Avoid placing the unit in a location where there is direct heat or splashing water. C. Install the unit on the mounting plate firmly. D. Place the unit as far away as possible from TV, radio, etc. to prevent interference. GROUNDING INSTRUCTIONS For personal safety,
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OPERATING INSTRUCTIONS CONTROL PANEL 1 2 4 3 7 5 6 10 8 9 11 12 13 16 14 15 18 17 21 19 20 4-1
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CONTROL PANEL INSTRUCTIONS 1. DISPLAY: The Display includes a clock and indicators to 12. TIME COOK: Touch this pad to set a cooking time. tell you time of day, cooking time settings and cooking functions selected. 13. POWER LEVEL: Touch this pad to select a cooking power level. 2. POPCORN: Touch this pad when popping popcorn in your microwave oven. 14. CUSTOM SET: Touch this pad to change the oven’s default settings for sound, clock, display speed, defrost 3. POTATO: Touch this pad to cook pota
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OVERALL CIRCUIT DIAGRAM SCHEMATIC DIAGRAM 5-1
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MATRIX CIRCUIT FOR TOUCH KEY BOARD AUTO TIME COOK COOK AUTO AUTO CUSTOM REHEAT DEFROST SET KITCHEN CLOCK Ez On TIMER TIME POWER N.C DEFROST LEVEL STOP/ N.C CLEAR 5-2
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GENERAL INFORMATION FOR SERVICE FEATURES AND SPECIFICATIONS GENERAL PRECAUTIONS IN USE FEATURES A. Never operate the unit when it is empty. Operating the oven with no load may shorten the A. The safety systems incorporated in this model are: life of the magnetron. Whenever cooking dry foods (1) Primary interlock switch (dried fish, bread, etc.) or a small amount of food, (2) Secondary interlock switch be sure to put a glass of water into the cooking (3) Interlock monitor switch compartment.
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SERVICE INFORMATION PRECAUTIONS AND REPAIR SERVICE TIPS PRELIMINARY (3) Do not operate the unit until it is completely A. SINCE NEARLY 2,100 VOLTS EXISTS IN SOME repaired, if any of the following conditions exist. CIRCUITS OF THIS UNIT REPAIRS SHOULD BE The unit must not be operated. CARRIED OUT WITH GREAT CARE. (a) The door does not close firmly. The filament leads of magnetron carry High (b) The hinge is broken. Voltage with respect to ground. Extreme caution (c) The door seal is damaged
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MICROWAVE LEAKAGE TEST MEASURING MICROWAVE ENERGY CAUTIONS LEAKAGE • Be sure to check microwave leakage prior to servicing the oven if the oven is operative prior to • Pour 275±15cc of 20±5°C(68±9°F) water in a beaker servicing. which is graduated to 600 cc, and place the beaker • The service personnel should inform the on the center of the turntable. manufacture importer, or assembler of any certified • Set the energy leakage monitor to 2,450 MHz and oven unit found to have a microwave emission
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MEASUREMENT WITH THE OUTER CASE NOTE WHEN MEASURING (1) Do not exceed meter full scale deflection. REMOVED (2) The test probe must be moved no faster than (1) When you replace the magnetron, measure for 1 inch/sec (2.5cm/sec) along the shaded area, microwave energy leakage before the outer case otherwise a false reading may result. is installed and after all necessary components (3) The test probe must be held by the grip portion of are replaced or adjusted. Special care should be the hand
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DISASSEMBLY INSTRUCTIONS (4) Remove 3 screws securing the circuit board. IMPORTANT NOTES: UNIT MUST BE DISCONNECTED FROM ELEC- TRICAL OUTLET WHEN MAKING REPAIRS, RE- PLACEMENTS, ADJUSTMENTS AND CONTIN- UITY CHECKS. WAIT AT LEAST ONE MINUTE, UNTIL THE HIGH VOLTAGE CAPACITOR IN THE HIGH VOLTAGE POWER SUPPLY HAS FULLY DISCHARGED. THE CAPACITOR SHOULD BE DISCHARGED BY USING INSULATED WIRE - I.E. TEST PROBE CONNECTED TO 10K-OHM RESISTOR IN SERIES TO GROUND. WHEN RECONNECTING THE WIRE LEADS TO ANY
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HOW TO INSERT THE F.P.C. CONNECTOR HOW TO REMOVE THE F.P.C. CONNECTOR Follow the steps below as illustrated in Figures 6 Follow the steps below as illustrated in Figures 4 and 7 to insert the F.P.C. connector. and 5 to remove the F.P.C. connector. (1) Insert the F.P.C. connector into the terminal socket securely with the fingers. (1) Hold the edges of the plastic fastener with (2) Hold the plastic fastener with thumb and thumb and forefinger. forefinger of the other hand, and push it (Fig
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B. REMOVING THE OUT CASE(Figure 8) (6) Remove the power cord cover from outcase by (1) Remove the vent grille by removing two screws removing a screw. securing it to the out case. (7) Remove the power cord to the inner of the out c (2) Remove two screws securing it to the front bracket. ase with turning power cord and remove the out (3) Remove two screws securing it to the air duct. case with pushing it back. (4) Remove the mounting plate by turning the two screws securing it to the out case. (
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C REMOVING THE DOOR INTERLOCK SWITCHES (Figures 9,10) (1) Disconnect the wire leads from the interlock switches. (2) Remove two screws securing the Latch Board. (3) Make necessary replacements and check microwave energy leakage according to “ADJUSTMENT PROCEDURE” on page 7-12. Latch Board Secondary Interlock Switch Latch Board Secondary Interlock Switch WH(from H.V.Transformer) WH(from Monitor S/W) WH(from Oven Thermostat) WH(from Cooktop lamp Interlock Monitor Switch Primary Interlock
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NOTES: D. REMOVING MAGNETRON • When removing the magnetron, make sure that its (Figures 11 Through 13) dome does not hit any adjacent parts, or it may be (1) Remove vertgrille. damaged. (2) Remove mount all. (3) Remove outcase. • When replacing the magnetron, be sure to install the (4) Discinnect the wireleads. magnetron gasket in the correct position and be sure (5) Remove the 3 screws and Magnetron very that the gasket is in good condition. carefully. • After replacing the magnetron, check fo
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E. REMOVING DOOR (Figure 14) (1) Remove the vent grille by two screws securing it to the outcase loosening. (2) Lift up and draw the door. NOTES: • After replacing the door, be sure to check that the primary interlock switch, the secondary interlock switch and the interlock monitor switch is in good operating normally. • After replacing the door, check for microwave energy leakage with a survey meter. Microwave energy 2 leakage must be below the limit of 5mW/cm . (With a 275 ml water load) Fi
