Dacor MMD24S, Service Manual

Page 1: ...y high voltage and current Contact with the following parts may result in a severe possibly fatal electrical shock High Voltage Capacitor High Voltage Power Transformer High Voltage Rectifier and Heat...

Page 2: ...r seal and microwave generation and transmission systems shall be repaired replaced or adjusted by procedures described in this manual before the oven is released to the owner e A microwave leakage ch...

Page 3: ...neccessary covers 2 Open the drawer and keep it open 3 Discharge high voltage capacitor 4 Disconnect the leads to the primary of the power transformer 5 Ensure that the leads remain isolated from othe...

Page 4: ...275 15 ml 9 8 oz of tap water initially at 20 5O C 68O F in the center of the oven cavity The water container shall be a low form of 600 ml 20 oz beaker with an inside diameter of approx 8 5 cm 3 1 2...

Page 5: ...he door brackets and hinges are not defective C The door packing is not damaged D The door is not deformed or warped E There is no other visible damage with the oven Servicing and repair work must be...

Page 6: ...ull power throughout the cooking time P 90 approx 90 of Full Power P 80 approx 80 of Full Power P 70 approx 70 of Full Power P 60 approx 60 of Full Power P 50 approx 50 of Full Power P 40 approx 40 of...

Page 7: ...vided When installing this appliance observe all applicable codes and ordinances Where a two pronged wall receptacle is encountered it is the personal responsibility and obligation of the customer to...

Page 8: ...to the stir fan motor the cooling fan motor and the high voltage componentsarede energized theovenlampremainson and the digital read out displays the time still remaining in the cook cycle when the d...

Page 9: ...ooking Sequence 1 Touch one of the SENSOR pads NOTE The oven should not be operated on sensor immediately after plugging in the unit Wait two minutes before cooking on SENSOR 2 The coil of shut off re...

Page 10: ...TO SOURCE TO LOAD TO LOAD TO SOURCE SWITCHING SWITCH DOOR SENSING SENSOR FAN MOTOR HUMDITY F3 F2 F1 SM FM OL A3 COM N O STIRRER MOTOR OVEN LAMP SECONDARY INTERLOCK SWITCH RY3 RY1 RY2 CAPACITOR xxx F A...

Page 11: ...covers 2 Open the drawer and block it open 3 Discharge high voltage capacitor 4 Replace the Keyboard unit 5 Reconnect all leads removed from components during testing 6 Re install the covers 7 Reconn...

Page 12: ...regurator for drawer motor 8 Disconnect the power supply cord and then remove outer case 9 Open the door and block it open 10 Discharge high voltage capacitor 2 Open the drawer and block it open 3 Dis...

Page 13: ...tor has been burned replace the power unit 7 Examine the touch control transformer with a tester for the presence of layer short circuit check the primary coil resistance which is approximately 151 6...

Page 14: ...n cavity 3 Close the drawer 4 Touch the TIMER CLOCK pad once the POWER LEVEL pad twice and the START pad once And touch the number pads 1 once and the number pad 4 once Now the oven is in the sensor c...

Page 15: ...supply cord 9 Check the sensor cook operation proceed as follows 9 1 Close the door Touch the TIMER CLOCK pad once the POWER LEVEL pad twice and the START pad once And touch the number pads 1 once an...

Page 16: ...igital read out countdown 3 Remove the cup from the oven and again measure the temperature making sure to stir the thermometer or thermocouple through the water until the maximum temperature is record...

Page 17: ...meter should indicate a closed circuit When the monitor switch actuator is pushed by a screw driver through the lower latch hole on the front plate of the oven cavity with the drawer opened in this co...

Page 18: ...E FILAMENT AND HIGH VOLTAGE 2 Open the drawer and block it open 3 To discharge high voltage capacitor wait for 60 seconds 4 If the monitor fuse is blown when the drawer is opened check the primary int...

Page 19: ...n power is supplied 5 Indicator Circuit A circuit to drive the Liquid Crystal Displays LCD1 6 Power Source Circuit This circuit generates voltages necessary in the control unit from the AC line voltag...

Page 20: ...k oscillation frequency control output Output to control oscillation input of Xin 14 VCC IN Power source voltage 5V VC voltage of power source circuit input 15 P60 IN Plus signal coming from the Micro...

Page 21: ...line key on matrix is touched 39 P15 OUT Key strobe signal Signal applied to touch key section A pulse signal is input to P20 P23 terminal while one of J 10 line key on matrix is touched 40 P14 OUT Ke...

Page 22: ...IN Signal to synchronize LSI with commercial power source frequency This is the basic timing for all real time processing of LSI 61 AVSS IN A D converter power source voltage The power source voltage...

Page 23: ...as to change the resistance values in parallel with R45 R49 Changing HUMIDITY SENSOR CIRCUIT the resistance values results in that there is the same potential at both F 3 terminal of the absolute humi...

Page 24: ...l and the oven itself is so short that the two can t be separated For those models check and repair all the controls sensor related ones included of the touch control panel while keeping it connected...

Page 25: ...alloy solder it is recommend that a dedicated bit is used and that the iron temperature is adjusted accordingly 3 Soldering As the melting point of lead free solder Sn Ag Cu is higher and has poorer...

Page 26: ...rts Ovenlamp Magnetron Highvoltagetransformerand Oven cavity WARNING FOR WIRING 1 Disconnect the power supply cord 2 Make sure that a definite click can be heard when the microwave oven drawer is unla...

Page 27: ...s the 4 mounting screws holding the unit on to the wall or cabinet opening Fig 1 3 Close Drawer and carefully pull the unit out from opening and unplug the power supply cord 4 Remove top cover Fig 2 5...

Page 28: ...the black and white AC terminals from the Noise Filter PWB and green ground wire from the back plate Fig 4 2 Attach the black and white AC terminals from the new Power Cord to the Noise Filter as sho...

Page 29: ...r and lower position of the latch hook should be less than 0 5mm The vertical position of the latch hook should be adjusted so that the secondary interlock switch is activated with the drawer closed T...

Page 30: ...wing A Make sure that drawer sensing switch secondary interlock switch and monitor switch are operating properly Refer to chapter Test Procedures B An approved microwave survey meter should be used to...

Page 31: ...SWITCH ANGLE REMOVAL Fig S 1 Fig S 2 ACTUATOR REMOVAL ADJUSTMENT 1 Follow the Microwave Drawer disassembly as previously stated 2 Open the drawer and keep it open 3 To discharge the high voltage capac...

Page 32: ...ation 1 Proceed in reverse to reinstall the Auto Drawer Gear taking care that the gear teeth are set into the cavity angle correctly Fig G 2 RACK GEAR REMOVAL 1 Follow the Microwave Drawer disassembly...

Page 33: ...G or YLW RED RED GRY BLK WHT NOISE FILTER BOARD N H WHT COM YLW or BLK RED THIRD DOOR SWITCH N O YLW or ORG WHT ORG CONTROL UNIT CNK CNM CNN CNE SWITCHING POWER SUPPLY CN501 CN502 T1 1 2 3 4 5 GRN BLU...

Page 34: ...O D7 RY1 COM N O D10 RY3 D11 RY4 D12 RY5 H 1 H 3 H 2 H 4 H 5 H 7 H 6 AC 120V MICRO COM O L FM SM 0 1uF 50V NOTE IF NOT SPECIFIED 1SS270A 10G471K A 5 A 1 H 8 1 3 8 5 B 1 C10 C11 NOT INSERT PARTS T1 VR...

Page 35: ...1 K 5 4 7K R56 C52 M 5 4 7K 10K 10K R58 C51 R55 R57 SP D19 D20 Q22 Q21 C20 C21 Q20 AN5 CF1 4MHz 1 2 3 7 5 6 CONTROL UNIT 4 7K R13 4 7K R12 P05 P51 P57 C3 S22 S23 SEG22 SEG23 COM2 10uF 35V VR GND INT 4...

Page 36: ...C D E F G H A B C D E F G H Figure S 4 Printed Wiring Board of Power Unit 2 5A 3 1 2 FUSE T1 4 8 D3 ZD1 J10 RY1 D12 RY5 DIP CNH Q1 R1 D2 D1 1 11 D4 1 1 R10 C10 RY2 1 3 P 3 D11 D10 7 CNA CNB C11 R11 RY...

Page 37: ...S0 S0 S24 C4 C5 R29 CF2 S24 C4 C5 C3 S0 C0 SP C90 C8 C6 C5 C3 C21 R27 R26 R28 C90 C90 R98 R96 R99 R95 D96 K D95 K D97 K Q97 R97 R41 J2 J1 J4 J6 K J3 C5 C6 D19 K D20 K ZD2 R7 1 1 8 6 Q26 WHA Q23 Q21 Q...

Page 38: ...INC ALL RIGHTS RESERVED Nopartofthispublicationmaybereproduced stored in retrieval systems or transmitted in any form or by any means electronic mechanical photocopying recording or otherwise without...