WARNING This product should be serviced only by trained qualified personnel. This service manual covers products for following markets. When troubleshooting or replacing parts, please refer to the country identifications shown below for your applicable product specification. ……For ……For Peru, Chile Panama, Mexico SAFETY PRECAUTIONS This device is to be serviced only by properly qualified service personnel. Consult the service manual for proper service procedures to assure continued safety operation and for precautions to be taken to avoid possible exposure to excessive microwave energy.
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POWER LEVEL & ACCESSORIES ITEM DESCRIPTION Control Complement Microwave Power for Variable Cooking Power level 800 Watts H G i gh 550 Watts M G e dium 440 Watts 220 Watts De G f rost 80 Watts L G o w Rating Label Location Inside Accessories...
CAUTIONS Unlike other appliances, the microwave oven is MICROWAVE RADIATION high-voltage and high-current equipment. Personnel should not be exposed to the Though it is free from danger in ordinary use, microwave energy which may radiate from the extreme care should be taken during repair. magnetron or other microwave generating device if it is improperly used or connection.
INSTALLATIONS BEFORE YOU BEGIN, READ THE FOLLOWING INSTRUCTIONS COMPLETELY AND CAREFULLY. INSTALLING EARTHING INSTRUCTIONS 1. Empty the microwave oven and clean inside it with This microwave oven is designed to be used in a fully a soft, damp cloth. Check for damage such as earthed condition.
OPERATING INSTRUCTIONS FEATURES Oven Front Plate See-Through oven window Door C Control Panel Safety Door Lock System Glass Tray Roller Ring CONTROL PANEL NN- ST342M (RPM) (1) Display Window (2) Micro Power Pad (3) Time Pads (4) Turbo Defrost Pads (5) Auto Reheat Pad (6) Auto Cook Pads (7) Serving/Weight Pad...
CONTROL PANEL NN- ST342M (RPH) Tecla de Palomitas de maiz Tecla de Recalentamiento Automático Tecla de Cocción Automática Tecla de Potencia Tecla de Descongelación Automática Tecla de Porciones/Peso Tecla de Minuto Automático Tecla de Más/Menos Teclas numéricas (10) Tecla de Cronómetro (11) Tecla de Reloj (12)
CIRCUIT DESCRIPTION power of microwave oven as POWER LEVEL. GENERAL DETAILS (refer to page 1-1) • The low voltage transformer supplies the necessary voltage to the micom controller when power cord is WHEN THE DOOR IS OPENED DURING plugged in. COOKING •...
SERVICE INFORMATION TOOLS AND MEASURING INSTRUMENTS NECESSARY TOOLS NECESSARY MEASURING INSTRUMENTS Tools normally used for TV servicing are sufficient. • TESTER(VOLTS-DC, AC., Ohmmeter) Standard tools are listed below. • Microwave survey meter • Diagonal pliers - Holaday HI-1500 • Long nose pliers HI-1501 •...
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MEASUREMENT WITH OUTER CASE NOTES WHEN MEASURING REMOVED • Do not exceed meter full scale deflection. • The test probe must be removed no faster than • When you replace the magnetron, measure for 1 inch/sec (2.5 cm/sec) along the shaded area, microwave energy leakage before the outer case is otherwise a false reading may result.
MEASUREMENT OF MICROWAVE POWER OUTPUT • Microwave power output measurement is made with is measured while the microwave generator is the microwave oven supplied at its rated voltage and operating at full power. Magnetron filament heat-up operated at its maximum microwave power setting with time is not included.
D. DOOR ASSEMBLY REMOVAL E. HIGH VOLTAGE TRANSFORMER REMOVAL 1) Open the door. 2) Remove two screws holding the Hinge 1) Discharge the high voltage capacitor. to the Cavity Ass'y. 2) Disconnect the leadwire from magnetron, high voltage CAUTION : Be careful not to damage Door C transformer, and capacitor.
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H. AIR GUIDE ASSEMBLY REMOVAL J. REMOVING THE TURNTABLE MOTOR 1) Disconnect the leadwire from lamp, A.C Relay and 1) Remove the glass tray monitor resistor and magnetron. 2) Remove the pully shaft VERY CAREFULLY 3) Lay the unit down on its back. 2) Remove the screw to the cavity.
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K. PCB ASSEMBLY REMOVAL L. INTERLOCK SYSTEM 1) Remove the control panel assembly from the 1) INTERLOCK MECHANISM cavity. The door lock mechanism is a device which has been specially designed to eliminate completely 2) Remove screws which hold the PCB to microwave activity when the door is opened during control panel.
INTERLOCK CONTINUITY TEST WARNING : FOR CONTINUED PROTECTION AGAINST EXCESSIVE RADIATION EMISSION, REPLACE ONLY WITH IDENTICAL REPLACEMENT PARTS. TYPE NO. KW3A FOR SWITCHS B. SECONDARY INTERLOCK SWITCH TEST A. PRIMARY INTERLOCK SWITCH TEST Disconnect the wire lead from the secondary When the door release button is depressed slowly switch.
COMPONENT TEST PROCEDURE CAUTIONS 1. DISCONNECT THE POWER SUPPLY CORD FROM THE OUTLET WHENEVER REMOVING THE OUTER CASE FROM THE UNIT. PROCEED WITH THE TEST ONLY AFTER DISCHARGING THE HIGH VOLTAGE CAPACITOR AND REMOVING THE WIRE LEADS FROM THE PRIMARY WINDING OF THE HIGH VOLTAGE TRANSFORMER.
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COMPONENTS TEST PROCEDURE RESULTS Antenna Gasket Chassis Filament NOTE: When testing the magnetron, be sure to install the magnetron gasket in the correct position and be sure that the gasket is in good condition. HIGH VOLTAGE Measure the resistance. Normal: Momentarily indicates CAPACITOR (Ohm-meter scale: Rx1000) several ohms, and then...
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COMPONENTS TEST PROCEDURE RESULTS FUSE Check for continuity of the fuse with an Normal Abnormal multi-meter. NOTE: If the fuse is blown, check the primary, the secondary, and the monitor switches, H.V.D. and H.V.C. before replacing the fuse. If the fuse is blown by improper switch operation replace the defective switch and the fuse at the same time.
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COMPONENTS TEST PROCEDURE RESULTS Ω FAN MOTOR Measure the resistance. Normal: 00~500 Abnormal: ∞ or several Ω (Wire leads removed) (Ohm-meter scale: R x 100) Ω Measure the resistance. TURNTABLE Normal: Approx. 100~200K Abnormal: ∞ or several Ω (Ohm-meter scale: R x 1000) MOTOR (Wire leads removed) NOTE : •...
TROUBLE SHOOTING WHEN YOU GET A COMPLAINT FROM YOUR CUSTOMER, EVALUATE THE COMPLAINT CAREFULLY. IF THE FOLLOWING SYMPTOMS APPLY, PLEASE INSTRUCT THE CUSTOMER IN THE PROPER USE OF THE MICROWAVE OVEN. THIS CAN ELIMINATE AN UNNECESSARY SERVICE CALL. CAUTIONS 1. Check grounding before checking for trouble. 2.
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(TROUBLE 1) The following visual conditions indicate a probable defective control circuit. 1. Incomplete segments. • Segment missing. • Partial segment missing. • Digit flickering (NOTE: Slight flickering is normal.) 2. Colon does not turn on or blink. 3. A distinct change in the brightness of one or more numbers in display. 4.
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(TROUBLE 2) Oven does not operate at all ; Display window does not display any figures and no input is accepted. CONDITION CHECK RESULT CAUSE REMEDY Replace primary Malfunction of the Check continuity 1. Fuse blows. Continuity. and monitor monitor switch. of monitor switches.
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(TROUBLE 3) Display shows all figures set, but oven does not start cooking while desired program times are set and START pad is touched. CONDITION CHECK RESULT CAUSE REMEDY Defective Replace Check continuity 1.Setting time does No continuity. secondary switch. secondary switch.
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(TROUBLE 5) No microwave oscillation even though oven lamp and fan motor run (Display operates properly) CONDITION CHECK RESULT CAUSE REMEDY Defective P.C.B No microwave Disconnect the Replace P.C.B No continuity. oscillation. wire leads from assembly assembly relay 2 and check continuity Continuity.
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(TROUBLE 6) Oven does not cook properly when programmed for the set power level (Operates properly on HIGH) CONDITION CHECK RESULT CAUSE REMEDY Output is full when Defective P.C.B. Replace P.C.B. Disconnect the Abnormal. you set lower assembly. assembly. wire leads from power level.
REPLACEMENT 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. For Model:NN-ST3 4 2M(RPM) Ref.No.
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REPLACEMENT PARTS LIST For Model:NN-ST3 4 2M(RPM) A632641V0ZP TURNTABLE MOTOR ! A302041V0ZP DOOR HOOK A ! A614141V0ZP MICROSWITCH MICROSWITCH(MONITOR ! A614241V0ZP SWITCH) A313641V0ZP HOOK SPACER ! ! A614541T0ZP THERMAL CUTOUT(OVEN) 120℃/0℃ 120℃/0℃ A402541V0ZP AIR GUIDE A A612E7W50BP LAMP(U) ! A900C41T0ZP AC CORD W/PLUG A030A41T0ZP LEAD WIRE HARNESS...
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REPLACEMENT 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. For Model:NN-ST3 4 2M(RPH ) Ref.No.
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REPLACEMENT PARTS LIST For Model:NN-ST3 4 2M(RPH ) 632641T0RP TURNTABLE MOTOR ! A302041V0ZP DOOR HOOK A ! A614141V0ZP MICROSWITCH MICROSWITCH(MONITOR ! A614241V0ZP SWITCH) A313641V0ZP HOOK SPACER ! A614541T0ZP THERMAL CUTOUT(OVEN) 120℃/0℃ A402541V0ZP AIR GUIDE A A612E41T0RP LAMP(U) ! A900C41T0RP AC CORD W/PLUG A030A41T0ZP LEAD WIRE HARNESS !...