NN-SN968B / NN-SN968BT 2 DESCRIPTION OF OPERATING SEQUENCE 2.1. Variable power cooking 2.3. Inverter defrost control When the Auto Control feature is selected and the Start button is tapped: High Voltage Inverter Power Supply (U) controls output power 1. The digital programer circuit determines the power level and by the signal from Digital Programmer Circuit (DPC).
NN-SN968B / NN-SN968BT 2.5. Sensor reheat Explanation of the Auto Sensor Cooking process 1. During the first 10 second period there is no microwave Auto Sensor Reheat is a quick and easy way to reheat activity. When calculating the T2 time by using the refrigerated and room temperature foods.
NN-SN968B / NN-SN968BT 3 CAUTIONS TO BE OBSERVED WHEN TROUBLESHOOTING Unlike many other appliances, the microwave oven is a high voltage, high current device. Though it is free from danger in ordinary use, extreme care should be taken during repair.
NN-SN968B / NN-SN968BT 3.6. Verification after repair Discharging the high voltage capacitors 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-SN968B / NN-SN968BT 4 DISASSEMBLY AND PARTS REPLACEMENT PROCEDURE 4.1. Magnetron 4.2. Digital programmer circuit (D.P.C) 1. Discharge high voltage charge. 2. Remove 1 screw holding air guide A on the oven cavity. CAUTION: 3. Remove 1 screw holding air guide B.
NN-SN968B / NN-SN968BT 4.3. Low voltage transformer 4.5. Door assembly and/or power relays (RY1, 1. Remove door C from door E by carefully pulling outward, RY2) starting from upper right hand corner using a flat blade screwdriver. CAUTION: 2. Separate door E from tabs on door A and remove door A.
NN-SN968B / NN-SN968BT 4.6. Turntable motor 4.7. Steam sensor 1. Remove the motor cover by breaking off at the 8 spots 1. Disconnect connector CN2 from digital programmer circuit indicated by arrows with a cutter or the like. board. 2. Disengage catch hooks on sensor cover C from orifice.
NN-SN968B / NN-SN968BT 4.8. Inverter power supply 6. Press 1 encircled locking tab and then slide 4 locking tabs of Inverter bracket at the bottom of the base in direction of CAUTIONS arrows. 1. Always leave the grounding plate in place.
NN-SN968B / NN-SN968BT 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-SN968B / NN-SN968BT 5.4. Inverter power supply (U) 5. Program oven at High power for 1 minute and press [Start] button. DO NOT try to REPAIR H.V. Inverter power supply (U). a. After approximately 3 seconds, oven stops operating. Replace complete H.V. Inverter(U) Unit.
NN-SN968B / NN-SN968BT 6 MEASUREMENTS AND ADJUSTMENTS 6.1. Adjustment of primary latch switch, secondary latch switch and monitor interlock switch. 1. Mount the Primary latch switch, the Secondary latch switch and the Monitor interlock switch to the door hook assembly as shown in illustration.
NN-SN968B / NN-SN968BT 7 PROCEDURE FOR MEASURING MICROWAVE ENERGY LEAKAGE 7.2.1. Measurement with the outer panel removed. Whenever you replace the magnetron, measure for radiation leakage before the outer panel is installed and after all necessary components are replaced or adjusted. Special care should be taken in measuring around the magnetron.
NN-SN968B / NN-SN968BT 8 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-SN968B / NN-SN968BT 8.2. (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-SN968B / NN-SN968BT 8.3. 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-SN968B / NN-SN968BT 8.4. Trouble related to Digital Programmer Circuit SYMPTOM STEP CHECK RESULT CAUSE/CORRECTIONS No display when oven is first plugged Fuse pattern of D.P.C. Normal →Step2 Open Replace D.P.C. or Fuse Pattern Low voltage transforment (L.V.T.) Abnormal 0V L.V.T.
NN-SN968B / NN-SN968BT 8.5. SIMPLE WAY OF H.V. INVERTER/MAGNETRON TROUBLESHOOTING Purpose: Simple way (3/37 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.
NN-SN968B / NN-SN968BT 9.2. 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.
NN-SN968B / NN-SN968BT 9.3. ESCUTCHEON BASE ASSEMBLY Ref. No. Part No. Part Name & Description Pcs/Set Remarks F603L8W70AP D.P.CIRCUIT (AU) F603Y8W70AP D.P.CIRCUIT (DU) F80347B00BAP ESCUTCHEON BASE F66164W20AP FLAT CABLE F82987D60KAP BUTTON F80726G40BAP DOOR OPENING BUTTON F82565W00AP DOOR OPENING LEVER F80375K00AP...
NN-SN968B / NN-SN968BT 9.4. DOOR ASSEMBLY Ref. No. Part No. Part Name & Description Pcs/Set Remarks F30186P40AG DOOR KEY A F30016G40BAP DOOR A F302K4U00AP DOOR E (U) F30215G10XN DOOR KEY SPRING F30854U00AP DOOR C F31454U00AP DOOR SCREEN A F31468P40BAP DOOR SCREEN B...
NN-SN968B / NN-SN968BT 10.2. PARTS LIST Ref. No. Part No. Part Name & Description Pcs/Set Remarks BZ310 L0DDEA000014 BUZZER 2.0KHz F2A1V471B281 AL CHEM CAPACITOR 470µF/35V C13,C16 F2A1C220B624 AL CHEM CAPACITOR 22µF/16V C482 F2A1H1R0B574 AL CHEM CAPACITOR 1µF/50V C483 F2A1HR47B574 AL CHEM CAPACITOR 0.47µF/50V...