1 SCHEMATIC DIAGRAM 5
2 DESCRIPTION OF OPERATING SEQUENCE
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2.1. Variable power cooking control
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2.2. Inverter power supply circuit
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2.3. Turbo defrost, Auto cook
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2.4. Sensor cooking
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2.5. Steam sensor and digital programmer circuit
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3 CAUTIONS TO BE OBSERVED WHEN TROUBLESHOOTING
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3.1. Check the grounding
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3.2. Inverter warnings
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3.3. Part replacement.
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3.4. When the 10A fuse is blown due to the malfunction of the
short switch:
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3.5. Avoid inserting nails, wire etc. through any holes in the
unit during operation.
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3.6. Verification after repair
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3.7. Sharp edges
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4 DISASSEMBLY AND PARTS REPLACEMENT PROCEDURE
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4.1. Magnetron
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4.2. Digital programmer circuit (D.P.C)
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4.3. Low voltage transformer and/or power relays (RY1, RY2)
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4.4. Fan motor
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4.5. Door assembly
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4.6. Turntable motor
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4.7. Steam sensor
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4.8. Inverter power supply
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5 COMPONENT TEST PROCEDURE
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5.1. Primary, Secondary Latch Switch interlocks & Power
Relay RY1
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5.2. Short Switch
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5.3. Magnetron
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5.4. key board membrane (Membrane switch assembly)
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5.5. Inverter power supply (U)
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5.6. Temperature thermistor
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6 MEASUREMENTS AND ADJUSTMENTS
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6.1. Adjustment of primary latch switch, secondary latch switch
and short switch.
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6.2. Measurement of microwave output
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7 TROUBLESHOOTING GUIDE
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7.1. (Troubleshooting) Oven stops operation during cooking
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7.2. (Troubleshooting) Other problems
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7.3. Troubleshooting of inverter circuit (U) and magnetron
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7.4. Simple way of H.V. Inverter/magnetron troubleshooting
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7.5. How to check the semiconductors using an OHM meter
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7.6. H.V. INVERTER MAIN PARTS LIST (Z606YBA00QP)
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8 EXPLODED VIEW AND PARTS LIST
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8.1. EXPLODED VIEW
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8.2. PARTS LIST
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8.3. ESCUTCHEON BASE ASSEMBLY
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8.4. DOOR ASSEMBLY
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8.5. WIRING MATERIALS
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8.6. PACKING AND ACCESSORIES
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9 DIGITAL PROGRAMMER CIRCUIT
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9.1. SCHEMATIC DIAGRAM (NN-SD452W)
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9.2. SCHEMATIC DIAGRAM (NN-ST462M, ST452W)
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CONTENTS
Page Page
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NN-SD452W / NN-ST462M / NN-ST452W