NN-SD698S / NN-ST678S / NN-ST658W 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 pad is tapped: High Voltage Inverter Power Supply (U) controls output power 1.
NN-SD698S / NN-ST678S / NN-ST658W Explanation of the Auto Sensor Cooking process 2.5. Sensor reheat 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-SD698S / NN-ST678S / NN-ST658W 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.
NN-SD698S / NN-ST678S / NN-ST658W 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-SD698S / NN-ST678S / NN-ST658W 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 A on the magnetron.
NN-SD698S / NN-ST678S / NN-ST658W 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.
NN-SD698S / NN-ST678S / NN-ST658W 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.
NN-SD698S / NN-ST678S / NN-ST658W 6. Press 1 encircled locking tab and then slide 4 locking tabs 4.8. Inverter power supply of Inverter bracket at the bottom of the base in direction of CAUTIONS arrows. 1. Always leave the grounding plate in place.
NN-SD698S / NN-ST678S / NN-ST658W 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-SD698S / NN-ST678S / NN-ST658W 5.5. Inverter power supply (U) 5. Program oven at High power for 1 minute and press [Start] DO NOT try to REPAIR H.V. Inverter power supply (U). pad. Replace complete H.V. Inverter(U) Unit. a. After approximately 3 seconds, oven stops operating.
NN-SD698S / NN-ST678S / NN-ST658W 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-SD698S / NN-ST678S / NN-ST658W 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-SD698S / NN-ST678S / NN-ST658W 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-SD698S / NN-ST678S / NN-ST658W 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-SD698S / NN-ST678S / NN-ST658W 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-SD698S / NN-ST678S / NN-ST658W 8.4. 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-SD698S / NN-ST678S / NN-ST658W 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-SD698S / NN-ST678S / NN-ST658W Ref. No. Part No. Part Name & Description Pcs/Set Remarks F65856K50AP INVERTER BRACKET F03347D00RP MENU LABEL SD698S F03347G50RP MENU LABEL ST678S,ST658W F40264T60APG AIR GUIDE B F00066G00RP CAUTION LABEL SD698S RPH,ST678S RPH...
NN-SD698S / NN-ST678S / NN-ST658W 9.4. DOOR ASSEMBLY Ref. No. Part No. Part Name & Description Pcs/Set Remarks F30186P40AG DOOR KEY A SD698S,ST678S F30184Y30XN DOOR KEY A ST658W F301A8X00SCP DOOR A (U) SD698S F301A8M00SAP DOOR A (U) ST678S F302K5L00AP DOOR E (U)