NN-DF383B 2 DESCRIPTION OF OPERATING SEQUENCE 2.1. Variable power cooking 2.3. Turbo defrost, Auto cook control When the Auto Control feature is selected and the Start pad is tapped: High Voltage Inverter Power Supply (U) controls output power by the signal from Digital Programmer Circuit (DPC). Power 1.
NN-DF383B Explanation of the Auto Sensor Cooking process 2.6. Grill cooking control 1. During the first 10 second period there is no microwave Grill cooking is accomplished by upper heaters only. One grill activity. When calculating the T2 time by using the cooking cycle is 33 seconds.
NN-DF383B 3 CAUTIONS TO BE OBSERVED WHEN TROUBLESHOOTING Unlike many other appliances, the microwave oven is a high WARNING DISCHARGE HIGH VOLATGE voltage, high current device. It is free from danger in ordinary CAPACITORS use, though extreme care should be taken during repair.
NN-DF383B Discharging the high voltage capacitors 3.6. Verification after repair WARNING 1. After repair or replacement of parts, make sure that the There is high voltage present with high current capabilities screws of the oven, etc. are neither loosen or missing.
NN-DF383B 4 DISASSEMBLY AND PARTS REPLACEMENT PROCEDURE CAUTION 4.1. H.V. Inverter To prevent electric shock, do not touch the metal bar connected to the heaters. CAUTION 1. Always leave the grounding plate in place. 2. Always securely tighten the ground screw through the bottom of the chassis (base).
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NN-DF383B 7. Remove 4 screws on inverter reinforcement bracket. 6. Remove 1 screw holding lamp bracket. 8. Remove 1 screw holding oven thermistor on the oven cavity.
NN-DF383B 9. Disconnect connector from oven lamp and fan motor 4.2. Magnetron terminals. 1. Steps same as disassembly of H.V. Inverter step 1 to step 2. Remove 1 screw holding thermistor on magnetron. 10. Take out the inverter reinforcement bracket A, inverter bracket and H.V.
NN-DF383B 5. Remove 4 screws holding the magnetron. 4.3. Digital programmer circuit (D.P.C) & Membrane Sheet NOTE: Be sure to ground any static electric charge built up on your body before handling the D.P.C. 1. Remove 1 screw holding escutcheon base on oven cavity front plate.
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NN-DF383B To replace membrane sheet To remove dial 8. Use tools such as kinfe etc. to lift the edge of membrane Insert the ruler (wrapped with a glove) as a lever to release sheet and peel off membrane sheet completely from the dial.
NN-DF383B 4.4. Low voltage transformer 4.5. Fan motor and/or power relays 1. Disconnect 2 lead wires from fan motor terminals. 2. Remove 2 screws holding fan motor and detach fan motor CAUTION: from oven assy. Be sure to ground any static electric charge built up in your body before handling the DPC.
NN-DF383B 4.6. Upper Heater (Heater BU) 4.7. Door assembly 1. Disconnect lead wires from right side of upper heater. 1. Remove left and right door key springs from door arm with plier. NOTE: Support door before removing door springs. 2. Remove 2 screws holding air guide B on oven cavity left side.
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NN-DF383B • Remove the left side screw. Release catch hooks. • Loose the right side screw. NOTE: (NOTE: Do not take out the screw) After replacement of the defective component parts of the door, reassemble it properly and adjustment so as to prevent an excessive microwave leakage.
NN-DF383B 4.8. Stirrer motor 4.9. Lower Heater (Heater AU) 1. Remove the motor cover by breaking off at the 8 spots 1. Remove left and right door key springs from door arm. indicated by arrows with a cutter or the like.
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NN-DF383B 6. Remove 1 screw holding orifice on base plate. 9. Release the catch hook holding orifice and then remove the orifice. 7. Remove base plate from oven assy. 8. Remove 4 screws holding lower heater panel on the bottom of oven cavity.
NN-DF383B 5 COMPONENT TEST PROCEDURE 5.3. Magnetron WARNING 1. High voltage is present at the output terminals of the High Voltage Inverter (U) including aluminum heat sink during any cook cycle. Continuity checks can only indicate an open filament or a 2.
NN-DF383B 5.5. Inverter power supply (U) a. After approximately 3 seconds, oven stops operating. b. During oven operation, input current DO NOT try to REPAIR H.V. Inverter power supply approximately 0.4A. (U).Replace complete H.V. Inverter(U) Unit. INPUT CURRENT FAILURE CODE Unplug CN701 0.4A...
NN-DF383B 6 MEASUREMENTS AND ADJUSTMENTS 6.1. Adjustment of Primary latch switch, Secondary latch switch and Short switch. 1. Mount the Primary latch switch, the Secondary latch switch and the Short switch to the door hook assembly as shown in illustration.
NN-DF383B 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.
NN-DF383B 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.
NN-DF383B 7.1. (Troubleshooting) Oven stops operation during cooking SYMPTOM CAUSE CORRECTIONS 1. Oven stops in 3 seconds after No input AC is supplied to H.V.Inverter (U) Latch Switch pressing [start] pad. CN702 terminals Power relay RY1 Loose lead wire connector CN701, CN702 Oven stops in 23 seconds after H.V.Inverter (U) operates by the control signals...
NN-DF383B 7.2. (Troubleshooting) Other problems SYMPTOM CAUSE CORRECTIONS 1. Oven is dead. 1. Open or loose lead wire harness Fuse is OK. 2. Open thermal cutout / thermistor Check thermal cutout is defective. No display and no operation at all.
NN-DF383B 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-DF383B 7.4. Trouble related to Digital Programmer Circuit SYMPTOM STEP CHECK RESULT CAUSE/CORRECTIONS →Step2 No display when oven is first plugged Fuse pattern of D.P.C. Normal Open Replace D.P.C. or Fuse Pattern IC10 pin4 voltage Abnormal 0V IC26 →Step3 Normal=12V...
NN-DF383B 7.5. 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.
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NN-DF383B 7.7. H.V. INVERTER MAIN PARTS LIST (F606YBA00QP/F606YBA00HP) Ref. No. Part No. Part Name & Description Pcs/Set Remarks Q701 B1JAEV000003 IGBT C701 ECWHC3B104JA FILM CAPACITOR 0.1µF,1000VDC C702 ECWF4305N851 FILM CAPACITOR 3µF,250VDC DB701 B0FBBQ000006 RECTIFIER BRIDGE L701 F5020W100AP CHOKE COIL R702...
NN-DF383B 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.
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NN-DF383B Ref. No. Part No. Part Name & Description Pcs/Set Remarks F00066W10MP CAUTION LABEL F00068H00YT CAUTION LABEL F1140BG00XP STOPPER XTWFL4+12T SCREW FOR MAGNETRON XTT4+8RDN SCREW FOR CABINET BODY F0284BG40YP NO. LABEL F00069K90HP CAUTION LABEL F01509K90HP NO TOUCHING LABEL F1221-1R40 CUSHION RUBBER...
NN-DF383B 8.4. DOOR ASSEMBLY Ref. No. Part No. Part Name & Description Pcs/Set Remarks F302ABG30BEP DOOR A (U) F3044-1R40 DOOR ARM (RIGHT) F3085BG00XP DOOR C J301PBG00XP DOOR E (U) F3044-1R40 DOOR ARM (LEFT) F3231BG00XP DOOR KEY SPRING A (THIN ONE)