Samsung ME1240SC Specifications
Contents
1. No Code No Description Specification Q ty Remark B001 3405 001055 SWITCH MICRO 125 250VAC 16A 200GF SPST N 1 PRI S W B002 3405 001033 SWITCH MICRO 125 250VAC 16A 200GF SPST N 1 MONITOR B004 3405 001034 SWITCH MICRO 125 250VAC 16A 200GF SPST N 1 DOOR S W 006 DE72 00138A BODY LATCH NC2000 0 6 0 8 1 2 PP 1 B009 DE66 00088A LEVER SWITCH NC2000 0 6 0 8 1 2 PP 1 B018 DE96 00115D ASSY BODY LATCH MW1255WA NC2000 BUTTON 1 001 DE70 00185G PANEL OUTER ME1260SA XAA PET PCM TO 6 1 M015 DE39 00040E ASSY POWER CORD MW1255WA XAA SJT AWG14 1 M018 DE47 40025A HOLDER FUSE KFSN L 16 15A NYLON 66 5G 1 M019 3601 001198 FUSE CARTRIDGE 250V 20A SLOW BLOW CERAMI 1 M020 DE96 00100A ASSY MOTOR FAN SMF NC2UA1 120V60HZ 2800R 1 M029 DE47 20033A THERMOSTAT PW 2N 80 70 125V15A 250V7 5A 1 031 DE47 20173A THERMOSTAT PW 2N 90 60 30 187Y 250V7 5A 1 M034 DE67 00106A COUPLER PPS 8g BRN MW1250WA NC 1 2 1 M035 OM75P 31 ESS ASSY MAGNETRON OM75P 31 ESS 1 M036 4713 001012 LAMP INCANDESCENT 130V 40W ORG BIL 2 1 M037 DE71 00164A COVER AIR MW1250WA NC 12 PP TB53 T1 7 1 M038 DE26 00090A TRANS H V SHV U12KA 120V 60HZ 2350V 3 0V 1 M039 2501 001015 C OIL 1 0uF 2100V BK 35X54X80 20mm 1 M040 DE61 50106A BRACKET HVC SECC T0 8 W31 L125 8 d M042 DE59 40001A DIODE H V HVR 1X 32B 12 1 M048 DE80 00024D BASE PLATE ME1260SB XAA SGCC1 T0 6 ENAME 12. 2 Specifications 2 1 Table of Specifications TIMER 99 MINUTES 99SECONDS POWER SOURCE 120V 60Hz AC POWER CONSUMPTION MICROWAVE 1 650W OUTPUT POWER 1200W 10 LEVEL POWER OPERATING FREQUENCY 2 450MHz MAGNETRON OM75P 31 ESS COOLING METHOD COOLING FAN MOTOR OUTSIDE DIMENSIONS 20 W x 11 5 H x 16 D NET WEIGHT 36 0 Ibs SHIPPING WEIGHT 40 0 Ibs 3 Operating Instructions 3 1 Control Panel EN One Minute Auto Auto NT Defrost Reheat 2Casserole 3 Pasta Reheat One Touch Instant Cook Popcorn Potato VEL Beverage Fresh Soften Vegetables Clock Sound Pizza Baby Frozen lMekthocolate 1 Chicken Nuggets 1Nachos Gear 2 Hot Dogs 2 chicken Wings Set user 3 French Fri Potato Skins A irozenSan wich Cheese Sticks 7 9 Power 0 Kitchen Level Timer Pause Cancel ME12405C 3 2 Features 8 External Views Door Ventilation Holes Light Safety Interlock Holes Control Pane Guge Rollen Open Door Push Button A 297mm ASM 249mm Le gt 413mm 4 Disassembly and Reassembly 4 1 Replacement of Magnetron Motor Assembly and Lamp Remove the magnetron including the shield case permanent magnet choke coils and capacitors all of which are contained in one assembly Disconnect all lead wires from the magnetron and l
3. OPTIONI p Kg cz OPTION 9 OPTION 4 GJ 10 E 4 51 oPTIONI OPTION 10 OPTION 5 9 MOFE JEE weg 107110 a a a af a 9 9 9 A KEY MATRIX E E ag C04 ECOLA 9 O PEE l c04 o I x o l D24 2 e m fem l ovp o Co 2 OPTION y 1N4148M SeLED 1 SCHEMAT G 8 2 P C B Parts List Code No Description Specification Q ty Remark 3501 001155 RELAY MINIATURE 24VDC 200MW 3000MA 1FORMA 10MS 10MS 1 RY01 3501 001188 RELAY POWER 24V DC 0 53W 1FormA 9 3ms 10mS 1 RY02 3708 001551 CONNECTOR FPC FFC PIC 14P 1 25mm STRAIGHT SN 1 CNO4 DE07 00021K LED DISPLAY CSQ 4246G 10 NC2000 CMO 40SEG 5 1 LED1 09 00054 IC MICOM TPM87CH47U OTP 16K QFP 44PIN 1 IC01 DE26 00037A TRANS L V SLV 4290U 120V 60Hz AC17V 7V 35 10 PIN 1 LVT1 DE30 20016A BUZZER CBE2220BA STICK 1 BUZ1 DE92 01089A ASSY PCB AUTO 120V60HZ LED1 RA S2LED1 00 MS1040WB 1 0401 001083 DIODE SWITCHING MM4148 100V 150MA LL 34 TP 14 D08 D12 D15 D23 0402 001080 DIODE RECTIFIER GF1G 400V 1A DO 214BA TP 3 D01 D03 0402 001298 DIODE BRIDGE DF06S 600V 1A SMD 4 TP 1 BDO1 0403 001288 DIODE ZENER ZMM55C5V1 4 8 5 4V 500MW LL 34 TP 1 2001 0501 000465 TR SMALL SIGNAL MMBT3904 NPN 350MW SOT 23 TP 30 300 1 TRO
4. um MICROWAVE OVEN ME1240SC SERVICE Manual EEE 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 SEA 5 0015 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 c Before turning on microwave power operated with the door open for any service test or inspection within b Make the following safety checks on the microwave generating all ovens to be serviced before activating compartments check the magnetron the magnetron or other microwave wave guide or transmission line and source and make repairs as necessary cavity for proper alignment integrity 1 Interlock operation and connections 2 proper door closing d Any defective or misadjusted 3 seal and sealing surfaces arcing components in the interlock monitor wear and other damage door seal and microwave generation 4 damage to or loosening of hinges and transmission systems shall be and latches repaired replaced or adjusted by 5 evidence of dropping or abuse procedures described in this manual before the oven is released to the owner e A microwave leakage check to verify compliance with the Federal performance s
5. lt CX Y g r _Je Sz z E H E pcp PATTERN Eom om m A w e WHT HT EN 9 0 a UN o 77 MGT TCO PRIMARY INTERLOCK DOOR S W GRN 086 POWER RELAY ORG EZI SENSOR OXG ASSY P C BOARD BLK BLU MAGNETRON HIGH VOLTAGE 9 DIODE BLK WM TO CHASSIS m BLK Paras SECONDARY SWITCH TOP A ug RED H Q ORG RED T ORG HIGH VOLTAGE CAPACITOR Le N BLU BLU A RED __ RED WHT A RED F DOOR SENSING SWITCH MONITOR SWITCH BLK BOTTOM CENTER 1 HIGH VOLTAGE WHT TRANSFORMER RED WHT POWER RELAY 21 This Service Manual is a property of Samsung Electronics Co Ltd Any unauthorized use of Manual can be punished under applicable International and or domestic law ELECTRONICS Samsung Electronics Co Ltd June 2003 Printed in Korea Code No DE68 03188A
6. C 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 3 Removal of Door E Following the procedure as shown in the figure insert and bend a thin metal plate between Door E and Door A until you hear the tick sound 1 Insertion depth of the thin metal plate should be 0 5mm or less 4 3 4 Removal of Key Door amp Spring Remove pin hinge from Door E Detach spring from Door E and key door Upper Hinge Key Door 4 3 4 Reassembly Test After replacement of the 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 door has no play between the inner door surface and oven front surface
7. If the door assembly is not mounted properly microwave energy may leak from the space between the door and oven 3 Do the microwave leakage test 4 4 Replacement of Fuse 1 Disconnect the oven from the power source 2 When 20A fuse blows out by the operation of interlock monitor switch failure replace the primary interlock switch door sensing switch monitor switch and power relay 3 When the above three switches operate properly check if any other part such as the control circuit board blower motor or high voltage transformer is defective 4 5 Replacement of Drive Motor 1 Take out the glass tray guide roller from cavity 2 Turn the oven upside down to replace the drive motor 3 Remove a screw securing the drive motor cover or disconnect the drive motor cover from base 0 plate by nipper 4 Disconnect all the lead wires from the drive motor dl 5 Remove screws securing the drive motor to the cavity 6 ii 9 Z PA IZ 2 2 288 AL TA 2 ZJE Drive Motor Cover Base Plate Remove the drive motor and the coupler When replacing the drive motor be sure to remount it in the correct position with the coupler 8 Connect all the leads to the drive motor 9 Screw the drive motor cover to the base plate with a screw driver Drive Motor 4 6 Replacement of Control Circuit Board 4
8. M049 DE31 10154A MOTOR SYNCHRONOUS M2HJ49ZR02 ST 16 50 60 1 051 DE71 00015A COVER CEILING CE2933 T0 3 W114 2 L121 1 M056 DE63 00021A CUSHION HVT MW6693G EPDM EPDM T10 5 W30 1 M099 DE66 90113A LEVER DOOR PP TB53 GH41 T2 5 12g NT 1 M132 DE61 40066A FOOT PP BLK 2 T001 DE74 20015G TRAY COOKING 3RD 1 0 T6 1150G 1 T017 DE97 00222A ASSY GUIDE ROLLER NC 1 2CUFT SPS C832 B 1 W002 DE39 00278A WIRE HARNESS A MW1255WA 7 1 16 7 3 Control and Door Parts List No Code No Description Specification Q ty Remark C003 RA N2LED1 50 ASSY PCB PARTS ME1240SC 120V60HZ 1 C004 DE34 00145F SWITCH MEMBRANE ME1240SC XAA SILVER ENGL 1 C005 DE64 00528D CONTROL PANEL ME1240SC XAA ABS VE0855 1 C006 DE61 70076A SPRING BUTTON HSWR PIO 6 OD19 L23 5T 1 C007 DE64 00532E BUTTON PUSH ME1240SC ABS HG0760SR S 1 C009 DE64 00533A WINDOW DISPLAY E DESIGN ABS SMOG 1 C082 ASSY CONTROL BOX 120V60Hz ME1240SC SILVE 1 S N A D002 DE64 00529E DOOR A ME1240SC XAA ABS HGO760SR 1 0003 DE63 00042A SCREEN DOOR CLEAR MW1250WA NC 12 PET TO 1 D004 DE94 00428A ASSY DOOR E COATING MW1250WA NC 12 BLK 1 D005 DE64 00248A FILM DOOR PE PC T0 15 178 5 306 1 0006 DE64 00184A DOOR C MW1250WA PP BLK 1 2CUFT NC200 1 D007 DE61 00193A SPRING KEY MW1255 HSWR PIO 6 D5 5 L19 1 D009 DE61 00246A HINGE DOOR UPPER MW8103SS SCP1
9. ventilation slots Inform the manufacturer of any oven found to have emission in excess of 5 mW cm Make repairs to bring the unit into compliance at no cost to owner and try to determine cause Instruct owner not to use oven until it has been brought into compliance CENTRAL SERVICE CENTER Service technicians 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 If the fuse is blown by the Interlock Monitor Switch Replace all of the following at the same time Secondary door sensing switch and power relay as well as the Interlock Monitor Switch The correct adjustment of these switches is described elsewhere in this manual Make sure that the fuse has the correct rating for the particular model being repaired Design Alteration Warning Use exact replacement parts only i e only those that are specified in the drawings and parts lists of this manual This is especially important for the Interlock switches described above Never alter or add to the mechanical or electrical design of the MWO Any design changes or additions will void the manufacturer s warranty Always unplug the unit s AC power cord from the AC power source before attempting to remove or reinstall any component
10. 1 0504 001008 TR DIGITAL RN2427 PNP 200MW 2 2K 10K SOT 23 TP 5 TRO9 TR13 0504 001080 TR DIGITAL KRC246S NPN 200mW 2 2K 10K SOT 23 TP 3 02 05 08 1202 000141 IC VOLTAGE 7033 SOT 89 3P SINGLE OV P 1 IC03 1203 001037 IC VOLTAGE REGULATOR 78L05 SOT 89 3P 185MIL PLASTIC 1 IC02 1405 000001 VARISTOR 470V 1250A 14x7 5mm TP 1 ZNR1 2007 000033 R CHIP 00HM 5 1 8W DA TP 3216 4 J11 J12 J13 J16 2007 000282 R CHIP 100KOHM 5 1 10W DA TP 2012 2 R27 R28 2007 000300 R CHIP 10KOHM 5 1 10W DA TP 2012 3 R07 R08 R09 2007 000346 R CHIP 1200HM 5 1 8W DA TP 3216 9 R19 R26 2007 000468 R CHIP 1KOHM 5 1 10W DA TP 2012 6 R01 R03 R05 R10 R13 2007 000546 R CHIP 20KOHM 5 1 10W DA TP 2012 1 R32 2007 000671 R CHIP 2KOHM 5 1 10W DA TP 2012 1 R02 2007 000931 R CHIP 4700HM 5 1 10W DA TP 2012 1 R06 2007 000941 R CHIP 47KOHM 5 1 10W DA TP 2012 5 R14 R18 2007 008496 R CHIP 19 1MOHM 1 1 8W DA TP 2012 2 R41 R43 2007 008497 R CHIP 30 9MOHM 1 1 10W DA TP 2012 2 R42 R44 2203 000192 C CERAMIC CHIP 100nF 80 20 50V Y5V TP 2012 7 08 12 20 22 2203 000444 1nF 10 50V X7R TP 2012 5 C13 C17 2401 000151 C AL 1000uF 20 25V GP TP 10x20 5 1 C02 2401 000244 C AL 100uF 20 10V GP TP 6 3x7 5 1 C03 2401 000911 C AL 22uF 20 16V GP TP 5x7 5 2 C04 C06 2401 002075 C AL 4 7uF 20 50V GP TP 5x11 5 1 C05 2401 002598 C AL 220uF 20 50V GP TP 10x16 5 1 C01 2802 000188 RESONATOR CERAMIC 8MHz 0 5 TP 10 0x5 0x8 0mm 1 XTL1 3711 000881 CONNE
11. 12 0 1 D010 DE61 00247A HINGE DOOR LOWER MW8103SS SCP1 12 0 1 D011 DE64 00210A KEY DOOR NC2000 0 6 0 8 1 2 PP BLK 1 D015 DE94 00427A ASSY DOOR SUB MW1250WA NC 12 BLK DOOR E 1 D049 ASSY DOOR ME1240SC SILVER 1 2 E DESIGN 1 S N A S N A SERVICE NOT AVAILABLE 17 7 4 Standard Parts List Code No Description Specification Q ty Remark DE60 10082H SCREW A 7 7 7 228 AX12 TOOTHED 1 P C EA DE60 10082H SCREW A 75 7 228 AX12 TOOTHED 3 PN OUT DE60 10098A SCREW ASSY TAP TITE GLD SWRCH18A ZPC2 PH TC M4X8 WT 2 M DRIV DE60 10098A SCREW ASSY TAP TITE GLD SWRCH18A ZPC2 PH TC M4X8 WT 1 HVD DE60 10195A SCREW STAR POLE SWCH18A 4 12 TH 2 ZNC 2 O PANEL DE60 10088A SCREW TAP PH FEFZY PLAIN PH M3 L8 2 ASSY C BOX DE60 10059A SCREW TAP TH SUS410 CR TH M4 L8 2 C CEILING DE60 10070A SCREW TAP TH FEFZY 2 SLOT TH M4 L12 3 B PLTE DE60 10070A SCREW TAP TH FEFZY 2 SLOT TH M4 L12 2 BD LAT DE60 10070A SCREW TAP TH FEFZY 2 SLOT TH M4 L12 2 CN BOX DE60 10070A SCREW TAP TH FEFZY 2 SLOT TH M4 L12 1 CV AIR DE60 10070A SCREW TAP TH FEFZY 2 SLOT TH M4 L12 2 MGT TCO DE60 10070A SCREW TAP TH FEFZY 2 SLOT TH M4 L12 2 MO FAN DE60 10070A SCREW TAP TH FEFZY 2 SLOT TH M4 L12 1 S M EA DE60 10012A SCREW TAP TITE SWR10 M4 L10 TH 3 ZPC2 1 O P
12. 6 1 Removal of Control Box 1 Be sure to ground any static electric charge in your body and never touch the control circuit 2 Disconnect the connectors from the control circuit board 3 Remove screws securing the control box assembly 4 Remove the screw securing the ground tail of the keyboard 4 6 2 Removal of P C B Assembly 1 Pull the lever end of the plastic fastener and remove the Flexible Printed Circuit FPC of membrane panel Screw 2 Remove screws securing the control circuit board 3 Lift up the control circuit board from the 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 gt 4 6 3 Removal of Window Display amp Membrane Panel 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 double faced adhesive tape Therefore applying hot air such as using of hair dryer is recommended for smoother removal 3 When installing new membrane key board make sure that the surface of escutcheon base is cleaned sufficiently so that any problems shorted contacts or uneven surface can be avoided 5 Alignment and Adjustments PRECAUTIO
13. CTOR HEADER BOX 3P 1R 2 5mm STRAIGHT SN 1 CNO3 3711 000939 CONNECTOR HEADER BOX 4P 1R 2 5mm STRAIGHT SN 1 CNO5 3711 004143 CONNECTOR HEADER BOX 2P 3P 1R 5mm 2 5mm STRAIGH 1 CNO2 DE39 60001A WIRE SO COPPER PI0 6 SN T 52MM TAPING WIRE 10 J01 J10 DE41 00247A PCB MAIN RA S2LED1 FR 1 1 T1 6 W197 L247 1 DE60 60012A PIN EYELET ID2 1 0D2 5 L3 0 SN BSP T0 25 2 20 9 Schematic Diagrams 9 1 Schematic Diagrams This Document can not be used without Samsung s authorization NOTE CIRCUIT SHOWN WITH DOOR IS OPENED POSITION WARNING NOTE FOR SERVICE REPLACEMENT USE 16 GA 105 C THERMOPLASTIC COVERED WIRE EXCEPT POWER MUST BE DISCONNECTED FOR HIGH VOLTAGE LEADS OR AS NOTED ON SPECIAL LEADS BEFORE SERVICING THIS APPLIANCE FUSE CAVITY TCO BLK SECONDARY S W SR PA 9 0 H V TRANS YEL BLE BLU O O P 5 BLK a ia O 2 I cs 27 B c ds 120V60Hz x gt SX WHT x Q FA FZ
14. DE60 10012A SCREW TAP TITE SWR10 M4 L10 TH 3 ZPC2 1 DE60 10080B SCREW WASHER 2S SWRCH18A ZP2 PH PI5 L10 4 MGT DE60 10080B SCREW WASHER 2S SWRCH18A ZP2 PH PI5 L10 4 TNS HV 18 8 P C B Diagrams 8 1 P C B Diagrams This Document can not be used without Samsung s authorization JR RELAY SENSI USA OPTION ue ag ES 25 4 Pa EM E WA in I 1 dis E 18 P amp 5 2 V FF 1 4148 D11 15 X IN P76 42 P75 43 P74 44 1 P713 P77 41 a o m P61 20 P65 24 21 CSQ 42466 TR44 KRA 26S 01 TR12 APA KRA2265S DOV A IR13 KRA2265 e ze e 45 S 777 1N4148M INA 1 4BM INA 148M 1N4 1 4BM BM 1N4148M j x XQ 015 016 017 D18 D20 SL SL S l 44 5 2 J J gy COMBI GRILL OPTION 6 a a Si a OPTION IS INSTANT INSTANT CANCEL TOOK AEHEAT 1 OPTZONI FROZEN v OPTION 3 HANDY PIZZA T pu
15. N 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 voltage 3 Before touching any oven components or wiring always unplug the oven from its power source and discharge the high voltage capacitor 5 1 High Voltage Transformer 1 Remove connectors from the transformer terminals and check continuity 2 Normal resistance readings are as follows SHV U12KA Secondary 84 50 5 Filament Shows Continuity Primary 0 3050 5 Room temperature 20 C Primary 5 2 Low Voltage Transformer Terminals 1 The low voltage transformer is located on the Resistance control circuit board Terminals 2 Remove the low voltage transformer from the SLV 4290U PCB Ass y and check continuity 3 Normal resistor reading is shown in the table 1 2 Input 3799 3 4 Output7V 10 2302 5 6 Output17V 31 912 5 3 Magnetron 1 Continuity checks can indicate only an open filament or a shorted magnetron To diagnose an open filament or shorted magnetron 2 Isolate the magnetron from the circuit by disconnecting its leads 3 A continuity check across the magnetron filament terminals should indicate one ohm or less 4 A continuity check between each filament terminal and magnetron case should read open Cooling Fins 5 4 High Voltage Capacitor 1 Check continuity of the capacitor with the meter s
16. SINCE STATIC DISCHARGE MAY DAMAGE IT ALWAYS TOUCH GROUND WHILE WORKING ON IT TO DISCHARGE ANY STATIC CHARGE BUILT UP 6 1 Electrical Malfunction SYMPTOM CAUSE CORRECTIONS Oven is dead Fuse is OK No display and no operation at all Open or loose lead wire harness Open thermal cutout Magnetron Open low voltage transformer Check fan motor when thermal cutout is defective Check Ass y PCB when LVT is defective No display and no operation at all Fuse is blown Shorted lead wire harness Defective Secondary latch switch NOTE 1 3 Defective monitor switch NOTE1 4 Shorted HVCapacitor 5 Shorted HVTransformer NOTE2 1 2 3 4 Defective Ass y PCB 1 2 Check adjustment of Secondary interlock monitor power relay door sensing switch 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 key input Program Key input is not in Sequence Open or loose connection of membrane key pad to Ass y PCB Shorted or open membrane panel Defective Ass y PCB Nea RO Refer to operation procedure Replace PCB main Timer starts countdown but no microwave oscillation No heat while oven lamp and fan motor turn on O
17. amp Remove a screw securing air cover Remove the air cover Remove screws securing the magnetron to the wave guide Take out the magnetron very carefully Remove tow from the back panel of fan motor assembly Take out the fan motor assembly Remove the oven lamp by rotating to pull out from hole of air cover 5 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 4 2 Replacement of High Voltage Transformer 1 Discharge the high voltage capacitor 2 Disconnect all the leads PRECAUTION 3 Remove the mounting bolts Servicemen should remove their watches whenever 4 Reconnect the leads correctly and firmly working close to or replacing the magnetron PRECAUTION There exists HIGH VOLTAGE ELECTRICITY with high current capabilities in the circuits of the HIGH VOLTAGE TRANSFORMER secondary and filament terminals It is extremely dangerous to work on or near these circuits with the oven energized DO NOT measure the voltage in the high voltage circuit including filament voltage of magnetron 4 3 Replacement of Door Assembly 4 3 1 Removal of Door Assembly Remove hex bolts securing the upper hinge and lower hinge Then remove the door assembly 4 3 2 Removal of Door
18. en Door Closed Secondary Interlock switch 0 6 Interlock Switch Replacement When Monitor switch COM NC 0 oo replacing faulty switches be sure switch mounting Door Sensing switch 0 tabs not bent broken or otherwise deficient their ability to secure the switches in place Primary Interlock 10 5 8 Output Power of Magnetron CAUTION MICROWAVE RADIATION PERSONNEL SHOULD NOT ALLOW EXPOSURE TO MICROWAVE RADIATION FROM MICROWAVE GENERATOR OR OTHER PARTS CONDUCTING MICROWAVE ENERGY The output power of the magnetron can be measured by performing a water temperature rise test Equipment needed Two 1 liter cylindrical borosilicate glass vessel Outside diameter 190 mm One glass thermometer with mercury column NOTE Check line voltage under load Low voltage will lower the magnetron output Make all temperature and time tests with accurate equipment 1 Fill the one liter glass vessel with water 2 Stir water in glass vessel with thermometer and record glass vessel s temperature T1 10 1 3 After moving the water into another glass vessel place it in the center of the cooking tray Set the oven to high power and operate for 41seconds exactly 3 seconds included as a holding time of magnetron oscillation 4 When heating is finished stir the water again with the thermometer and measure the temperature T2 5 Subtract T1 from T2 This will give you the wate
19. et at the highest resistance scale 2 Once the capacitor is charged a normal capacitor shows continuity for a short time and then indicates 9M9 3 A shorted capacitor will show continuous continuity 4 An open capacitor will show constant 9M 5 Resistance between each terminal and chassis should read infinite 5 5 High Voltage Diode Isolate the diode from the circuit by disconnecting its leads With the ohm meter set at the highest resistance scale measure across the diode terminals Reverse the meter leads and read the resistance A meter with 6V 9V or higher voltage batteries should be used to check the front to back resistance of the diode otherwise an infinite resistance may be read in both directions The resistance of a normal diode will be infinite in one direction and several hundred in the other direction Ne 5 6 Main Relay and Power Control Relay 1 The relays are located on the PCB Ass y Isolate them from the main circuit by disconnecting the leads 2 Operate the microwave oven with a water load in the oven Set the power level set to high 3 Check continuity between terminals of the relays after the start pad is pressed 5 7 Adjustment of Secondary Switch Door Sensing Switch and Monitor Switch Precaution For continued protection against radiation hazard replace parts in accordance with the wiring diagram and be sure to use the correct part number for the following switches Primary and secondary in
20. ff alignment of latch switches Open or loose connection of high voltage circuit especially magnetron filament circuit NOTE Large contact resistance will bring lower magnetron filament voltage and cause magnetron to lower output and or intermittent oscillation 3 Defective high voltage components H V Transformer H V Capacitor H V Diode Magnetron 4 Open or loose wiring of power relay 5 Defective Secondary latch switch 6 Defective power relay or Ass y PCB Ne Adjust door and latch switches Check high voltage component according to component test procedure and replace if it is defective Replace PCB main 13 6 1 Electrical Malfunction continued SYMPTOM CAUSE CORRECTIONS Oven lamp and fan motor turn on 1 Misadjustment or loose wiring of secondary latch switch 2 Defective Secondary latch switch Adjust door and latch switches Oven can program but timer does not start 1 Open or loose wiring of secondary interlock switch 2 Off alignment of Secondary interlock 3 Defective secondary interlock S W Adjust door and interlock Switches Microwave output is low Oven takes longer time to cook food 1 Decrease in power source voltage 2 Open or loose wiring of magnetron filament circuit Intermittent oscillation 3 Aging of magnetron Consult electrician Fan motor turns on when plugged in Loose wiring of door sensing switch Check wire of d
21. ons 1 High Voltage Warning Do not attempt to measure any of the high voltages 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 to the oven chassis Use a screwdriver 3 High voltage is maintained within specified limits by close tolerance safety related components and adjustments If the high voltage exceeds the specified limits check each of the special components PRECAUTION There exists HIGH VOLTAGE ELECTRICITY with high current capabilities in the circuits of the HIGH VOLTAGE TRANSFORMER secondary and filament terminals It is extremely dangerous to work on or near these circuits with the oven energized DO NOT measure the voltage in the high voltage circuit including filament voltage of magnetron H V Capacitor Touch chassis ground first then short to the high voltage capacitor terminal by using screwdriver or jumper wire Fig 1 1 Discharging High Voltage Capacitor PRECAUTION Never touch any circuit wiring with your hand nor with uninsulated tool during operation PRECAUTION Servicemen should remove their watches whenever working close to or replacing the magnetron
22. oor sensing Switch Oven does not operate and return to the plugged in mode Defective Ass y PCB Replace PCB main Loud buzzing noise can be heard 1 Loose fan and fan motor 2 Loose screws on H V Transformer 3 Shorted H V Diode Tighten screws of fan motor Tighten screws of H V Transformer Replace H V Diode Turntable motor does not rotate 1 Open or loose wiring of turntable motor 2 Defective turntable motor Replace turntable motor Oven stops operation during cooking 1 Open or loose wiring of Secondary interlock switch 2 Operation of thermal cutout Magnetron Adjust door and latch switches Sparks 1 Metallic ware or cooking dishes touching on the oven wall 2 Ceramic ware trimmed with gold or silver powder also causes sparks Inform the customer Do not use any type of cookware with metallic trimming Uneven cooking Uneven intensity of microwave due to its characteristics Wrap thinner parts of the food with aluminum foil Use plastic wrap or cover with a lid Stir once or twice while cooking foods such as soup cocoa or milk Noise from the turntable motor when it starts to operate Noise may result from the motor Replace turntable motor 14 7 Exploded Views and Parts List 7 1 Exploded Views D006 M132 hm ij 19 7 2 Main Parts List
23. or assembly Never defeat any of the B voltage interlocks Do not apply AC power to the unit or any of its assemblies unless all solid state heat sinks are correctly installed Some semiconductor solid state devices are easily damaged by static electricity Such components are called Electrostatically Sensitive Devices ESDs Examples include integrated circuits and field effect transistors Immediately before handling any semiconductor components or assemblies drain the electrostatic charge from your body by touching a known earth ground 16 Always connect a test instrument s ground lead to the instrument chassis ground before connecting the positive lead always remove the instrument s ground lead last 1 2 Special Servicing Precautions Continued 17 When checking the continuity of the witches or transformer always make sure that the power is OFF and one of the lead wires is disconnected 18 Components that are critical for safety are indicated in the circuit diagram by shading N or 19 Use replacement components that have the same ratings especially for flame resistance and dielectric strength specifications A replacement part that does not have the same safety characteristics as the original might create shock fire or other hazards NOTE Connect the oven to a 20A When connecting the oven to a 15A make sure that circuit breaker can operate 1 3 Special High Voltage Precauti
24. r temperature rise T 6 The output power is obtained by the following formula Output Power 4 187 x 1000 x 0 55 To 41 Heating Time sec 38 38 Counting Time sec 4 187 Coefficient for Water 1000 Water cc ANT Temperature Rise T1 T2 To Room Temperature Mc Cylindrical borosilicate glass weight 7 Normal temperature rise for this model is 9 3 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 if temperature rise is marginal 5 9 Sensor Error Cord Cause Countermeasure 1 Let oven cool for at least 5minutes error1 Shorted sensor s circuit 2 Check connection of the sensor if the sensor s circuit was shorted or not by the alien substance error2 Open sensor s circuit 1 Check connection of sensor s wire On the cooling mode sensors Vot was error3 1 Let oven cool for at least 5minutes not less than 4 7V within 3minutes 4 On the way to sensing the door was 1 Press the pause cancel pad and then you have to do error 11 5 10 Procedure for Measurement of Microwave Energy Leakage 1 Pour 275 15cc of 20 5 C 68 9 F water in a beaker which is graduated to 600cc and place the beaker in 2 Start to operate the oven and measure the leakage by the center of the oven using a microwave energy survey meter 3 Set survey meter
25. t 1 Do not exceed the limited scale 2 The test probe must be held on the grip of the handle otherwise a false reading may result when the operator s hand is between the handle and the probe 3 When high leakage is suspected do not move the probe horizontally along the oven surface this may cause damage to the probe 4 Follow the recommendation of the manufacturer of the microwave energy survey meter 5 13 Leakage Measuring Procedure 5 12 1 Record keeping and notification after measurement 1 After adjustment and repair of a radiation preventing device make a repair record for the measured values and keep the data 2 If the radiation leakage is more than 4mW cm after determining that all parts are in good condition functioning properly and the identical parts are replaced as listed in this manual notify that fact to CENTRAL SERVICE CENTER 5 12 2 At least once a year have the microwave energy survey meter checked for accuracy by its manufacturer 12 6 Troubleshooting PRECAUTION CHECK GROUNDING BEFORE CHECKING FOR TROUBLE BE CAREFUL OF THE HIGH VOLTAGE CIRCUIT DISCHARGE THE HIGH VOLTAGE CAPACITOR WHEN CHECKING THE CONTINUITY OF THE SWITCHES OR TRANSFORMER DISCONNECT ONE LEAD WIRE FROM THESE PARTS AND THEN CHECK CONTINUITY WITHOUT THE POWER SOURCE ON TO DO OTHERWISE MAY RESULT IN A FALSE READING OR DAMAGE TO YOUR METER DO NOT TOUCH ANY PART OF THE CIRCUIT OR THE CONTROL CIRCUIT BOARD
26. tandard should be performed on each oven prior to release to the owner 1 Precaution Follow these special safety precautions Although the microwave oven is completely safe during ordinary use repair work can be extremely hazardous due to possible exposure to microwave radiation as well as potentially lethal high voltages and currents 1 1 Safety precautions A 1 e R EA o All repairs should be done in accordance with the procedures described in this manual This product complies with Federal Performance Standard 21 CFR Subchapter J DHHS Microwave emission check should be performed to prior to servicing if the oven is operative If the oven operates with the door open Instruct the user not to operate the oven and contact the manufacturer and the center for devices and radiological health immediately Notify the Central Service Center if the microwave leakage exceeds 5 mW cm Check all grounds Do not power the MWO from a 2 prong AC cord Be sure that all of the built in protective devices are replaced Restore any missing protective shields When reinstalling the chassis and its assemblies be sure to restore all protective devices including nonmetallic control knobs and compartment covers Make sure that there are no cabinet openings through which people particularly children might insert objects and contact dangerous voltages Examples Lamp hole
27. terlock switches and the interlock monitor switch replace all together Then follow the adjustment procedures below After repair and adjustment be sure to check the continuity of all interlock switches and the interlock monitor switch When mounting Primary switch and Interlock Monitor switch to Latch Body consult the figure 2 No specific adjustment during installation of j Primary switch Secondary switch and gt Monitor switch to the latch body is necessary C Secondary d 3 When mounting the Latch Body to the oven 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 Body Latch Completely tighten the screws holding the Latch H Interlock Monitor Body to the oven assembly H z Switch 4 Reconnect to Monitor switch and check the Lever Switch continuity of the monitor circuit and all latch switches again by following the components test procedures Door Sensing Interlock Switch 5 Confirm that the gap between the switch housing and the switch actuator is no more than 0 5mm when door is closed Door Op
28. with dual ranges to 2 450MHz 4 When measuring the leakage always use the 2 inch spacer cone with the probe Hold the probe perpendicular to the cabinet door Place the spacer cone of the probe on the door and or cabinet door seam and move along the seam the door viewing window and the exhaust openings moving the probe in a clockwise direction at a rate of 1 inch sec If the leakage testing of the cabinet door seam is taken near a corner of the door keep the probe perpendicular to the areas making sure that the probe end at the base of the cone does not get closer than 5cm to any metal If it gets closer than 5cm erroneous readings may result 5 Measured leakage must be less than 4mW cm after repair or adjustment Maximum allowable leakage is 5mW cm 4mW em is used to allow for measurement and meter accuracy 5 11 Check for Microwave Leakage 1 Remove the outer panel 2 Pour 275 15cc of 20 5 C 68 9 F water in a beaker which is graduated to 600cc and place the beaker in the center of the oven Start the oven at the highest power level Set survey meter dual ranges to 2 450MHz Using the survey meter and spacer cone as described above measure near the opening of magnetron the surface of the air guide and the surface of the wave guide as shown in the following photo but avoid the high voltage components The reading should be less than 4mW cm oR OW 5 12 Note on Measuremen
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