ORDER NO.PAPMOSH1201015CE Microwave Oven NN-SD452W NN-ST462M NN-ST452W BPQ (U.K.) EPG (Continental Europe) © Panasonic Appliances (Shanghai) Co., Ltd. 2012.
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NN-SD452W / NN-ST462M / NN-ST452W CONTENTS Page 1 SCHEMATIC DIAGRAM 5 2 DESCRIPTION OF OPERATING SEQUENCE 6 Page 5.1. Primary, Secondary Latch Switch interlocks & Power Relay RY1 15 2.1. Variable power cooking control 6 5.2. Short Switch 15 2.2. Inverter power supply circuit 6 5.3. Magnetron 15 2.3. Turbo defrost, Auto cook 6 5.4. key board membrane (Membrane switch assembly) 15 2.4. Sensor cooking 6 5.5. Inverter power supply (U) 16 2.5.
NN-SD452W / NN-ST462M / NN-ST452W 1 SCHEMATIC DIAGRAM 5
NN-SD452W / NN-ST462M / NN-ST452W 2 DESCRIPTION OF OPERATING SEQUENCE 2.1. Variable power cooking control 2.4. Auto sensor cooking without setting a power level or selecting a time. All that is necessary is to select an Auto Sensor Program before starting to cook. High Voltage Inverter Power Supply (U) controls output power by the signal from Digital Programmer Circuit (DPC). Power relay always stay on, but PWM (Pulse Width Modulation) signal controls microwave output power.
NN-SD452W / NN-ST462M / NN-ST452W Explanation of the Auto Sensor Cooking process 1. During the first 10 second period there is no microwave activity. When calculating the T2 time by using the formula below make sure this 10 seconds is subtracted from the T1 time. In other words, T1 time starts at the end of the 10 second period. 2. T1 time The total amount of time it takes the microwave oven to switch to T2 time after the 10second period. 3.
NN-SD452W / NN-ST462M / NN-ST452W 3 CAUTIONS TO BE OBSERVED WHEN TROUBLESHOOTING Unlike many other appliances, the microwave oven is a high voltage, high current device. It is free from danger in ordinary use, though extreme care should be taken during repair. CAUTION Servicemen should remove their watches & rings whenever working close to or replacing the magnetron. 3.1. Check the grounding Do not operate on a two wire extension cord. The microwave oven is designed to be grounded when used.
NN-SD452W / NN-ST462M / NN-ST452W 3.6. Discharging the high voltage capacitors WARNING 1. After repair or replacement of parts, make sure that the screws of the oven, etc. are neither loosen or missing. Microwave energy might leak if screws are not properly tightened. There is high voltage present with high current capabilities in the circuits of the primary and secondary windings, choke coil and heat sink of the inverter.
NN-SD452W / NN-ST462M / NN-ST452W 4 DISASSEMBLY AND PARTS REPLACEMENT PROCEDURE 4.1. Magnetron 1. Discharge the high voltage capacitor. 2. Remove 1 screw holding air guide A on the magnetron. 3. Remove 1 screw holding air guide A on cavity top plate. 4. Remove 1 screws holding thermistor on the magnetron. NOTE: After replacement of the magnetron, tighten mounting screws properly, making sure there is no gap between the waveguide and the magnetron to prevent microwave leakage.
NN-SD452W / NN-ST462M / NN-ST452W 4.5. Door assembly 1. Support the door, remove 3 screws holding hinge A. 4.3. Low voltage transformer and/or power relays (RY1, RY2) CAUTION: 2. Open the door, remove door(U) and hinge A from cavity. Be sure to ground any static electric charge built up in your body before handling the DPC. NOTE: Support the door before opening. 1. Replace D.P.C. board.
NN-SD452W / NN-ST462M / NN-ST452W 9. Tighten 2 mounting screws. 6. Replace other components. To re-install components: NOTE: After replacement of the defective component parts of the door, reassemble it properly and adjustment so as to prevent an excessive microwave leakage. Adjustment of the door assembly (Refer page 17). 7. Place the hole of hinge A into the door’s upper hinge pin. Be sure the gap between door E and cavity front plate will be 0.3~0.7mm.
NN-SD452W / NN-ST462M / NN-ST452W 4.6. Turntable motor 4.7. 1. Remove the motor cover by breaking off at the 8 spots indicated by arrows with a cutter or the like. Steam sensor 1. Disconnect connector CN2 from digital programmer circuit board. 2. Disengage catch hooks on sensor cover C from orifice. NOTE: After removing the motor cover, be sure that cut portions are properly trimmed or bent to the inside so that no sharp edges will be exposed to outside. 3. Remove steam sensor from orifice. 2.
NN-SD452W / NN-ST462M / NN-ST452W 4.8. Inverter power supply 6. Remove 1 screw holding H.V.Inverter to Inverter bracket. CAUTIONS 1. Always leave the grounding plate in place. 2. Always securely tighten the ground screw through the bottom of the chassis (base). 3. Securely connect 3 lead wire connectors. 4. Make sure the heat sink has enough space (gap) from the oven. Take special care not to dress any lead wire over the aluminum heat sink because it is hot. 1. Discharge high voltage charge. 2.
NN-SD452W / NN-ST462M / NN-ST452W 5 COMPONENT TEST PROCEDURE 5.3. WARNING 1. High voltage is present at the output terminals of the High Voltage Inverter (U) including aluminum heat sink 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 power cord and discharge the high voltage capacitors (see page 8). 5.1.
NN-SD452W / NN-ST462M / NN-ST452W 5.5. Inverter power supply (U) 3. Plug in the oven’s AC power supply cord into outlet. 4. Program DPC. DO NOT try to REPAIR H.V. Inverter power supply (U).Replace complete H.V. Inverter(U) Unit. For SD452W model a. Press Clock button once. b. Press Timer button once. c. Press Start button once. d. Press 1000W/600W button once. For ST462M & ST452W models a. Press Timer pad twice. b. Press Start pad once. c. Press Micro Power pad once. 5.
NN-SD452W / NN-ST462M / NN-ST452W 6 MEASUREMENTS AND ADJUSTMENTS 6.1. Adjustment of primary latch switch, secondary latch switch and short switch. 6.2. Measurement of microwave output The output power of the magnetron can be determined by performing IEC standard test procedures. However,due to the complexity of IEC test procedures, it is recommended to test the magnetron using the simple method outlined below. 1.
NN-SD452W / NN-ST462M / NN-ST452W 7 TROUBLESHOOTING GUIDE DANGER: HIGH VOLTAGES 1. DO NOT RE-ADJUST PRESET CONTROL on the H.V.Inverter (U). It is very dangerous to repair or adjust without proper test equipment because this circuit generates very large current and high voltage. Operating a misaligned inverter circuit is dangerous. 2. Ensure proper grounding before troubleshooting. 3. Be careful of the high voltage circuitry, taking necessary precautions when troubleshooting. 4.
NN-SD452W / NN-ST462M / NN-ST452W 7.2. (Troubleshooting) Other problems SYMPTOM 1. Oven is dead. Fuse is OK. No display and no operation at all. 2. No display and no operation at all. Fuse is blown. 3. Oven does not accept key input (Program) 4. Fan motor turns on when oven is plugged in with door closed. 5. Timer starts count down but no microwave oscillation. (No heat while oven lamp and fan motor turn on) 1. 2. 3. 4. 1. 2. 3. 4. 1. 2. 3. 4. 1. 2. 3. 1. 2. 3. 6.
NN-SD452W / NN-ST462M / NN-ST452W 7.3. Troubleshooting of inverter circuit (U) and magnetron This oven is programmed with a self diagnostics failure code system which will help for troubleshooting. H95, H97, H98 and H99 are the provided failure codes to indicate magnetron and inverter circuit problem areas. This section explains failure codes of H95, H97, H98 and H99.
NN-SD452W / NN-ST462M / NN-ST452W 7.4. Simple way of H.V. Inverter/magnetron troubleshooting Purpose: Simple way (3/23 seconds rule) of identifying whether it’s Magnetron, Inverter, or others. Set-up: The unit under question is connected through the Ammeter as shown below. Procedure: Follow the matrix table below to identify the problem source. Note: Do not replace both Inverter board and Magnetron simultaneously and automatically without going through this procedure.
NN-SD452W / NN-ST462M / NN-ST452W 7.6. H.V. INVERTER MAIN PARTS LIST (Z606YBA00QP) Ref. No. Q701 C701 C702 DB701 L701 R702 T701 D701,D702 C706 C707 Part No. Z1JAEV000003 ZCWHC3B104JA ZCWF4305N851 Z0FBBQ000006 Z5020W100AP Z0CM562JA002 Z609ABA00GP Z0FBAZ000003 Z0C3F562A002 Z0C3F822A002 Part Name & Description IGBT FILM CAPACITOR FILM CAPACITOR RECTIFIER BRIDGE CHOKE COIL SAND BAR RESISTOR TRANSFORMER DIODE FILM CAPACITOR FILM CAPACITOR Pcs/Set 1 1 1 1 1 1 1 2 1 1 22 Remarks 0.
NN-SD452W / NN-ST462M / NN-ST452W 8 EXPLODED VIEW AND PARTS LIST 8.1.
NN-SD452W / NN-ST462M / NN-ST452W 8.2. PARTS LIST NOTE: 1. When ordering replacement part(s), please use part number(s) shown in this part list. Do not use description of the part. 2. Important safety notice: Components identified by mark have special characteristics important for safety. When replacing any of these components, use only manufacture’s specified parts. Ref. No. 1 1 2 4 5 Part No.
NN-SD452W / NN-ST462M / NN-ST452W 8.3. 8.3.1. ESCUTCHEON BASE ASSEMBLY NN-SD452W Ref. No. E1 E2 E3 E4 E5 Part No. Z603L9Y70EP Z603Y9Y70EP Z80349Y70HEP Z891P9Y00HAP Z83379Y70HEP Part Name & Description D.P.CIRCUIT (AU) D.P.
NN-SD452W / NN-ST462M / NN-ST452W 8.3.2. NN-ST462M, ST452W Ref. No. E21 E23 E23 E24 E24 E25 E25 Part No. Z603L9Y60BP Z80349Y10SHP Z80349Y10HAP Z891P9Y60SBP Z891P9Y00HAP Z630Y9Y60SBP Z630Y9Y60HBP Part Name & Description D.P.
NN-SD452W / NN-ST462M / NN-ST452W 8.4. DOOR ASSEMBLY Ref. No. D1 D2 D2 D2 D3 D4 D5 Part No.
NN-SD452W / NN-ST462M / NN-ST452W 8.5. Ref. No. W1 W2 WIRING MATERIALS Part No. Z030A9Y60BP Z030E9Y10QP Part Name & Description LEAD WIRE HARNESS H.V.
NN-SD452W / NN-ST462M / NN-ST452W 8.6. PACKING AND ACCESSORIES Ref. No. P1 P1 P2 P2 P2 P3 P4 P5 Part No. Z00039Y60BP Z00039Y70EP Z01029Y70HEP Z01029Y60SBP Z01029Y60HBP Z01049Y00AP Z01059Y00AP Z01068100XN Part Name & Description INSTRUCTION MANUAL INSTRUCTION MANUAL PACKING CASE,PAPER PACKING CASE,PAPER PACKING CASE,PAPER UPPER FILLER LOWER FILLER P.E.
NN-SD452W / NN-ST462M / NN-ST452W 9 DIGITAL PROGRAMMER CIRCUIT 9.1.
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NN-SD452W / NN-ST462M / NN-ST452W 9.2.
NN-SD452W / NN-ST462M / NN-ST452W 33 01/12 S-9Y6, S-9Y7 Printed in China
