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MOP0408003S2 Microwave Oven NN-A774SBEPG NN-A734MBEPG NN-A764WBEPG NN-A764WBWPG ! WARNING This service information is designed for experienced repair technicians only and is not designed for use by the general public. It does not contain warnings or cautions to advise non-technical individuals of potential dangers in attempting to service a product.
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Power source 230 V AC Single Phase 50Hz Power requirements Microwave 1250W Grill 1350W Convection 1470W Combi 2770W Output (IEC60705) Microwave 1000W Grill1300W Convection 1400W Microwave frequency 2450Mhz Timer 99 min 99 second Oven cavity size Outside dimensions 510mm(W) x 477mm(D) X 304MM (H) Inside dimensions 359mm(W) X 352mm(D) x 217mm(H) Weight...
3 Control Panel NN-A774/NN-A734/NN-A764* Display Window Time Pads Microwave Power Pad Grill Power Pad Convection Pad Grill Convection Pad Combination Pad Auto Defrost Pad Weight Select Pads (10) Clock Pad AUTO / (11) Delay/Stand Pad (12) Auto Weight Program Pads 10min (13) Panacrunch Program Pads (14) Start Pad:...
4 Inverter Warnings The inverter circuit board supplies the magnetron tube with a very high voltage (4000 volts). HIGH VOLTAGE AREA *1 HEAT SINK DO NOT TOUCH RECTIFIER BRIDGE HOT/HIGH VOLTAGE *2 FILM CAPACITORS CHOKE COIL CN 702 SAND BAR RESISTOR HIGH VOLTAGE CURRENT TRANSFORMER DIODES...
5 Schematic Diagram MAGNETRON MAGNETRON 2M236-M42 Note : Door is closed. Note : Door is closed. Unit is not operated Unit is not operated NOISE FILTER NOISE FILTER CN703 CN701 2.0mH THERMAL CUT OUT THERMAL CUT OUT 8A 0R 10A 8A 0R 10A (OVEN) (OVEN)
6 Wiring Diagram NOTE WHEN REPLACIN ANY COMPONENT S RECONNECT THE WIRE HARNESS ACCORDIN T O THE COLOURS BELOW COL OURS INDICATED INSIDE BRACKETS () INDICATE THE COLOUR O THE CONNECTOR HOUSIN MA NETRON PRIMARY LATCH SWITCH CAUTION HEAT SINK (WH) (YE) (HOT LI E)
7 Description of the Operating Sequence 7.1 Variable power cooking control pad pressed: The output power is controlled by the inverter power 1. The digital programmer circuit determines the supply. The level of output from the inverter circuit is power level and the cooking time and indicates the controlled by a pulse width modulated signal from the operating state in the display.
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Auto Weight Cook Category 1st Touch weight Cooking time 1. Reheat 300g 3 Min 00 Sec 2. Frozen Reheat 300g 7 Min 00 Sec 3. Vegetables 500g 10 Min 20 Sec 4. Fish 500g 5 Min 00 Sec 5. Rice 200g 14 Min 45 Sec 6.
8 Cautions to be Observed when Troubleshooting The microwave oven is a high voltage, high current This high voltage inverter power supply supplies very device. Although it is free from danger in ordinary use, high voltage and current to the magnetron. Though it extreme care should be taken during repair.
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work on or near these inverter circuit components. DO NOT measure the voltage in the high voltage circuit including the filament voltage of the magnetron. H.V.INVERTER(U) WARNING Never touch any circuit wiring during operation. GROUNDING PLATE 8.3 Part replacement CHECK GROUNDING When replacing any component in the microwave oven, always ensure that the power cord is removed from the...
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When the appliance is operated with the door hinges or magnetron fixed incorrectly, the microwave leakage can reach more than 5mW/cm . After repair or replac- ing parts, it is very important to check if the magnetron and the door hinges are correctly fixed. 8.7 Sharp edges Please use caution when unpacking, installing or mov- ing the unit, as some exposed edges may be sharp to...
9 Parts Replacement Procedure 9.1 Magnetron 4. Remove the 1 screw holding the earth wire to the magnetron. 1. Discharge the high voltage capacitors on the 5. Remove the connector CN701 and CN702 from the inverter circuit. inverter PCB.figure 8 2.
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9.3 Digital Programmer Circuit (DPC) 1. Carefully remove all solder from the terminal pins of and membrane key board. the low voltage transformer / power relays using a NOTE: Ground any static electric from your body before 30W soldering iron and a solder sucker. handling the digital programmer circuit (DPC).
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After replacing component parts of the door, fol- low the instructions below for proper installation and adjustment of the door, this is to prevent microwave leakage. 1. When mounting the door to the oven, adjust the door parallel to the bottom of the oven face plate by adjusting the upper hinge.
10 Component Test Procedure Caution 3. Check the continuity between each filament termi- nal and the magnetron case, a good magnetron ∞ • The inverter circuit operates at high voltages. indicates infinite resistance. • Never attempt to measure the high voltage on the inverter circuit.
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DANGER HIGH VOLTAGE AND HIGH TEMPERATURE (HOT/LIVE) HEAT SINK HEAT SINK RECTIFIER BRIDGE FILM CAPACITORS CHOKE COIL CN 702 SAND BAR RESISTOR HIGH VOLTAGE CURRENT TRANSFORMER DIODES PRESET VOLUME *4 (DO NOT ADJUST) HIGH VOLTAGE CAPACITORS CONTROL BOARD WITH CUSTOM IC CN 703 PHOTOCOUPLER HIGH VOLTAGE TRANSFORMER...
11 Measurements and Adjustments Warning 4. Stir the water again and read the temperature of the water. (Record as T2). • Only replace parts with parts from the original man- 5. The normal temperature rise at the high power posi- ufacturer.
12 Troubleshooting Guide Caution 1. Do not try to repair the H.V. Inverter power supply. Replace the inverter circuit board as a complete unit. 2. Do not adjust the preset volume on the Inverter. It is very dangerous to repair or adjust without special test equiptment, the inverter handles very high voltage and current.
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12.1 Troubleshooting (no operation) Symptom Cause Correction 1. Oven is dead. 1. Open or loose lead wire harness. Fuse is OK 2. Open low voltage transformer. No display and no operation at all. 3. Defective DPC AU or DPC DU 2.
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12.3 Troubleshooting (other problems) Symptom Cause Correction 1. Microwave output is low. 1. Decrease in power source volt- Consult electrician. Oven takes a long time to cook food. age. Refer to output test procedures. 2. Open or loose wiring of magne- tron filament circuit causing inter- mittent oscillation.
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DANGER H97, H98 appears in HIGH the display window. VOLTAGE Open Check magnetron *Check the continuity of the magnetron Magnetron* filament continuity filament. Check the fialment is not shorted to the magnetron case.. DPC board/Power relay Check Inverter input AC Loose relay wiring voltages at CN702 Latch switch...
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DANGER H97, H98 appears in HIGH the display window. VOLTAGE DPC board/Power Relay Less than 0.4A Loose wiring. Check oven input Latch Switch. current. DPC control signal More than 0.5A *Check the continuity of the magnetron Open Check magnetron filament. Check the fialment is not shorted to the Magnetron* filament continuity.
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Microwave oven shuts down Unplug CN702 connec- Abnormal 1. Latch switch between 15 - 33 seconds. tor and measure the 2. DPC/Power relay Set the microwave oven to test voltage between the Normal Step 2 mode (See page ) terminlas Set to high power 1 minute.
13 Parts List • When ordering parts quote the part number, do not use the description of the part. • Components identified by the following symbol (!) have special safety characteristics. Only replace these parts with parts supplied by the original manufacturer. Ref.
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Ref. No. Part No. Part Description Comments AEE6142-1450 Primary Latch Switch E30208000BP Door Hook AEE9108A20GN Holder XTWANE 4+ 12B Screws For Magnetron 2M236-M42G1 Magnetron E22434V00BP Adiabatic Material XTWANE 4 + 8BN Screw AEE0926000AN Cushion Rubber E66014V00GP Inverter Earth Bracket E65854V00BP Inverter Support Bracket E606Y4V00BP Inverter...
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Ref. No. Part No. Part Description Comments E67579000BP Heater bracket D E22784V00SGP Upper Heater Cover E00064080BP Warning Label...
15 Door Assembly A774SB Ref no Part Number Part name & description Remarks E302A6R10SEP DOOR A ASSEMBLY A774SB E30214000AP DOOR KEY SPRING E30184L00GS DOOR KEY (!) E302K6R00BP DOOR E ASSEMBLY E30854V00BP DOOR C NOTE: When ordering any Door component also order door C as this part may become damaged during disassembly...
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A734MB, A764WB Ref no Part Number Part name & description Remarks E302A6R10NBP DOOR A ASSEMBLY A734MB E302A6R10HBP DOOR A ASSEMBLY A764WB E30214000AP DOOR KEY SPRING E30184L00GS DOOR KEY (!) E302K6R00BP DOOR E ASSEMBLY E30854V00BP DOOR C NOTE: When ordering any Door component also order door C as this part may become damaged during disassembly.
16 Escutcheon Base NN-A774SB M ic ro p G ri ll 1 -2 -3 ti o rb o -B a in a ti o 81 3A Ref. No. Part No. Part Name & Description Remarks E80725D00SBP Door Opening Button E80378A0AG Door Opening Spring E800S6R10SBP Escutcheon Base Unit...
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NN-A754, NN-A724 Ref. No. Part No. Part Name & Description Remarks E80726R00HBP Door Opening Button A764WB E80726R00NBP Door Opening Button A734MB E80378A0AG Door Opening Spring E83376R10HEP Escutcheon Sheet A764WBEPG, A734MB E83376R10HSP Escutcheon Sheet A764WBWPG E80346R00HBP Escutcheon Base A764WB E80346R00NBP Escutcheon Base A734MB E80246R10HEP Operation Buttons...
17 Packing and Accessories Ref. No. Part No. Part Name & Description Remarks E10859040BP Pan Handle E01134N80EP Tray Styrol E290D4N00BP Roller Ring E060W9040ET Crispy Pan E01695750BP Service Centre List E00036R10EP Operating Instruction EPG Models E00036R10WP Operating Instruction WPG Model E000B6R10EP Cook Book EPG Models E000B6R10EP...
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Ref. No. Part No. Part Name & Description Remarks EE02146700BP Door Sheet E01109010GS Vinyl Bag...
18 Trim Kit Accessories Trim Model No. Top and Bottom Strip ref 1 Qty Left and Right Strip ref 2 Qty Remarks NN-TKA70AB E1603A510ABP E1601A510ABP A714AB NN-TKA70MB E1603A510NBP E1601A510NBP A734MB NN-TKA70WB E1603A510HBP E1601A510HBP A74WB E000QA820BP Installation Guide...