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MICROWAVE OVEN

MW7490W

SERVICE 

Manual

MICROWAVE OVEN

CONTENTS

1. Precaution

2. Specifications

3. Operating Instructions

4. Disassembly and Reassembly

5. Alignment and Adjustments

6. Troubleshooting

7. Exploded Views and Parts List

8. PCB Diagrams

9. Schematic Diagrams

SECA

Summary of Contents for MW7490W

Page 1: ...anual MICROWAVE OVEN CONTENTS 1 Precaution 2 Specifications 3 Operating Instructions 4 Disassembly and Reassembly 5 Alignment and Adjustments 6 Troubleshooting 7 Exploded Views and Parts List 8 PCB Diagrams 9 Schematic Diagrams SECA ...

Page 2: ...nicians should remove their watches while repairing an MWO 11 To avoid any possible radiation hazard replace parts in accordance with the wiring diagram Also use only the exact replacements for the following parts Primary and secondary interlock switches interlock monitor switch 12 If the fuse is blown by the Interlock Monitor Switch Replace all of the following at the same time Primary door sensi...

Page 3: ...ages this includes the filament voltage of the magnetron High voltage is present during any cook cycle Before touching any components or wiring always unplug the oven and discharge the high voltage capacitor See Figure 1 1 2 The high voltage capacitor remains charged about 30 seconds after disconnection Short the negative terminal of the high voltage capacitor to the oven chassis Use a screwdriver...

Page 4: ...NDS POWER SOURCE 120V 60HZ AC POWER CONSUMPTION MICROWAVE 1 450W OUTPUT POWER FROM 100W TO 1000W 10 LEVEL POWER IEC 705 TEST PROCEDURE OPERATING FREQUENCY 2 450MHz MAGNETRON OM75PH 31 ESS COOLING METHOD COOLING FAN MOTOR OUTSIDE DIMENSIONS 217 8 W x 125 16 H x 1621 32 D NET WEIGHT 38 6 lbs SHIPPING WEIGHT 43 lbs ...

Page 5: ...r Button Auto Defrost Auto Reheat Pause Cancel Start Clock Kitchen Timer One Minute Popcorn Diet Cook Frozen Dinner 1 2 3 4 5 6 7 8 9 0 More Less Power Level MW7490W Baby Food Potato Fresh Vegetable 3 Operating Instructions 3 1 Control Panel 3 2 Features External Views Door Ventilation Holes Light Safety Interlock Holes Control Panel Open Door Push Button Guide Roller Glass Tray Door Latches 556mm...

Page 6: ...e back panel of fan motor assembly 6 Take out the fan motor assembly 7 Remove the oven lamp by pulling out from hole of air cover NOTE1 When removing the magnetron make sure that its antenna does not hit any adjacent parts or it may be damaged NOTE2 When replacing the magnetron be sure to remount the magnetron gasket in the correct position and make sure the gasket is in good condition 1 Discharge...

Page 7: ... a thin metal plate between Door E and Door A until you hear the tick sound Insertion depth of the thin metal plate should be 0 5mm or less Insert flat screwdriver into the gap between Door A and Door C to remove Door C Be careful when handling Door C because it is fragile Then remove the door assembly 4 3 1 Removal of Door C 4 3 2 Removal of Door E Disassembly and Reassembly Door C Door A Door E ...

Page 8: ...defective component parts of the door reassemble it and follow the instructions below for proper installation and adjustment so as to prevent an excessive microwave leakage 1 When mounting the door to the oven be sure to adjust the door parallel to the bottom line of the oven face plate by moving the upper hinge and lower hinge in the direction necessary for proper alignment 2 Adjust so that the d...

Page 9: ...e Ass y control box 4 When reconnecting the FPC connector make sure that the holes on the connector are properly engaged with the hooks on the Plastic Fastener 1 Window display should not be disassembled as its mounting tabs will be broken If repair work is difficult replace with Ass y control panel 2 The membrane key board is attached to the escutcheon base with doublefaced adhesive tape Therefor...

Page 10: ...and magnetron case should read open 1 The low voltage transformer is located on the control circuit board 2 Remove the low voltage transformer from the PCB Ass y and check continuity 3 Normal resistor reading is shown in the table PRECAUTION 1 High voltage is present at the high voltage terminals during any cook cycle 2 It is neither necessary nor advisable to attempt measurement of the high volta...

Page 11: ...n assembly adjust the Latch Body by moving it so that the oven door will not have any play in it Check for play in the door by pulling the door assembly Make sure that the latch keys move smoothly after adjustment is completed Completely tighten the screws holding the Latch Body to the oven assembly 4 Reconnect to Monitor switch and check the continuity of the monitor circuit and all latch switche...

Page 12: ...tir the water again with the thermometer and measure the temperature T2 5 Subtract T1 from T2 This will give you the water temperature rise T 6 The output power is obtained by the following formula 7 Normal temperature rise for this model is 9 9 C to 10 5 C at HIGH NOTE 1 Variations or errors in the test procedure will cause a variance in the temperature rise Additional power test should be made i...

Page 13: ...r of a radiarion preventing device make a repair record for the measured values and keep the data 2 If the radiation leakage is more than 5 mW cm2 after determining that all parts are in good condition functioning properly and the identical parts are replaced as listed in this manual notift that fact to CENTRAL SERVICE CENTER 5 12 2 At least once a year have the microwave energy survey meter check...

Page 14: ...r sensing switch 3 Defective monitor switch NOTE1 4 Shorted HVCapacitor 5 Shorted HVTransformer NOTE2 NOTE 1 All of these switches must be replaced at the same time refer to adjustment instructions Check continuity of power relay contacts and if it has continuity replace power relay also NOTE 2 When HVTransformer is replaced check diode and magnetron also Oven does not accept 1 Key input is not in...

Page 15: ... 1 Loose fan and fan motor Tighten screws of fan motor 2 Loose screws on H V Transformer Tighten screws of H V Transformer 3 Shorted H V Diode Replace H V Diode Turntable motor does not rotate 1 Open or loose wiring of turntable motor Check the wire of turntable motor 2 Defective turntable motor Replace turntable motor Oven stops operation during cooking 1 Open or loose wiring of primary Adjust do...

Page 16: ...ics 7 Exploded Views and Parts List 7 1 Exploded Views 7 1 M1 M2 M21 M22 M26 M25 M11 M13 M14 M15 M12 M16 M17 M18 M19 M20 M3 M4 M5 M6 M7 M8 M9 M10 B1 B2 B2 B4 B3 M27 M23 C1 C2 C3 C4 C5 C6 C7 C8 M24 D1 D2 D3 D5 D6 D4 D7 ...

Page 17: ...3RD W 1 M12 DE26 00006A TRANS H V SHV 5593UC 120V60HZ 2195V 3 60V DY 1 M13 2501 001105 C OIL 950nF 2 1KV BK 54x35x80 20 1 M14 DE61 50106A BRACKET HVC SECC T0 8 W31 L125 8 1 M15 DE59 40001A DIODE H V HVR 1X 32B 12 1 M16 DE74 20002A TRAY COOKING GLASS T6 PI360 1 2CUFT NEG 1 M17 DE97 00009A ASSY GUIDE ROLLER MW7896W D16 5 BLK XARAC 1 M18 DE67 60082A COUPLER PPS T5 3XL24 1 BRN 3RD W 1 3 MW7896W 1 M19 ...

Page 18: ... 20010A BUTTON PUSH ABS VH 080 WHT 17 6G MW4370W 1 C 2 DE61 70076A SPRING BUTTON HSWR PI0 6 1 C 3 DE34 10207T SWITCH MEMBRANE PET MW7490W XAC 3RD 1 3 1 C 4 DE72 70162A CONTROL PANEL ABS 250G T2 5 1 C 5 RA W3LCD2 01 ASSY PCB PARTS 1 C 6 DE93 30405J ASSY CONTROL PANEL MW7490W WHT 3RD 1 3CU FT NEWGUARD 1 C 7 DE64 00044A WINDOW COVER HIDDEN ABS HR0370U BLK MW4390W LCD N G 1 C 8 DE67 40003E WINDOW DISP...

Page 19: ...DE60 10082H SCREW A 2S 4X12 TOOTHED 2 MO FAN DE60 10082H SCREW A 2S 4X12 TOOTHED 1 P C EA DE60 10082H SCREW A 2S 4X12 TOOTHED 5 PN OUT DE60 10082H SCREW A 2S 4X12 TOOTHED 1 S M EA DE60 10088A SCREW TAP PH PH M3 L8 FEFZY PLAIN 1 MGT TCO DE60 10098A SCREW ASSY TAP TITE PH TC M4X8 SWRCH18A ZPC2 GLD W 2 M DRIV DE60 10088A SCREW TAP PH PH M3 L8 FEFZY PLAIN 2 DE60 10098A SCREW ASSY TAP TITE PH TC M4X8 S...

Page 20: ...8 P C B Diagrams 8 1 P C B Diagrams Samsung Electronics 8 1 ...

Page 21: ...3 R31 R32 R33 P20 2001 000435 R CARBON 1MOHM 5 1 8W AA TP 1 8X3 2MM 1 R25 P21 2001 000515 R CARBON 220OHM 5 1 8W AA TP 1 8X3 2MM 1 R15 P22 2001 000577 R CARBON 2KOHM 5 1 8W AA TP 1 8X3 2MM 2 R05 R13 P23 2001 000613 R CARBON 3 9KOHM 5 1 8W AA TP 1 8X3 2MM 1 R11 P24 2001 000780 R CARBON 470OHM 5 1 8W AA TP 1 8X3 2MM 1 R09 R12 P25 2001 000841 R CARBON 51OHM 5 1 4W AA TP 2 4X6 4MM 1 R01 P26 2011 00107...

Page 22: ...IGH VOLTAGE LEADS OR AS NOTED ON SPECIAL LEADS POWER MUST BE DISCONNECTED BEFORE SERVICING THIS APPLIANCE C1 120V 20A C2 C3 0 1uF 500kohm 0 9mH 200pF 200pF BLK BLU BLK R RED RED ORG RED BLK BLU RED ORG ORG BLU BLK MAGNETRON HIGH VOLTAGE DIODE TO CHASSIS FA F HIGH VOLTAGE TRANSFORMER POWER RELAY DOOR SENSING SWITCH BOTTOM MONITOR SWITCH CENTER BLK PRIMARY SWITCH TOP HIGH VOLTAGE CAPACITOR BLK RED O...

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