MODEL 721.67902 721.67903 721.67909
DIVISION 20
BASIC FIELD MANUAL
FOR
MICROWAVE OVEN
MODEL 721.67902600 721.67903600 721.67909600
JUNE, 2006
CAUTION
WARNING TO SERVICE TECHNICIANS
PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICING TO AVOID POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY
a.Do not operate or allow the oven to be operated with the door open.
b.Make the following safety checks on all ovens to be serviced before activating the magnetron or other microwave source, and make repairs as necessary; (1) Interlock operation, (2) proper door closing, (3) seal and sealing surfaces (arcing, wear, and other damage), (4) damage to or loosening of hinges and latches, (5) evidence of dropping or abuse.
c.Before turning on microwave for any service test or inspection within the microwave generating compartments, check the magnetron, wave guide or transmission line, and cavity for proper alignment, integrity, and connections.
d.Any defective or misadjusted components in the interlock, monitor, door seal, and microwave generation and transmission systems shall be repaired adjusted by procedures described in this manual before the oven is released to the owner.
e.A Microwave leakage check to verify compliance with the Federal performance standard should be performed on each oven prior to release to the owner.
•Proper operation of the microwave ovens requires that the magnetron be assembled to the wave guide and cavity. Never operate the magnetron unless it is properly installed.
•Be sure that the magnetron gasket is properly installed around the dome of the tube whenever installing the magnetron.
•Routine service safety procedures should be exercised at all times.
•Untrained personnel should not attempt service without a thorough review of the test procedures and safety information contained in this manual.
CONTENTS
MODEL 721.67902 721.67903 721.67909
(Page)
SAFETY PRECAUTIONS - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Inside front cover
SPECIFICATIONS - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1-1
CAUTIONS - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2-1
INSTALLATIONS - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 3-1
OPERATING INSTRUCTIONS - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-1
FEATURES - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-1 CONTROL PANEL - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-1 OPERATING SEQUENCE - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-2 SCHEMATIC DIAGRAM - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-3 CIRCUIT DESCRIPTION - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-4
SERVICE INFORMATION - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 5-1
TOOLS AND MEASURING INSTRUMENTS - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 5-1 MICROWAVE LEAKAGE TEST - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 5-1 MEASUREMENT OF MICROWAVE POWER OUTPUT - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 5-3 DISASSEMBLY AND ADJUSTMENT - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 5-3 INTERLOCK CONTINUITY TEST - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 5-8 COMPONENT TEST PROCEDURE - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 5-9 TROUBLE SHOOTING - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 5-14
EXPLODED VIEW - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 6-1 REPLACEMENT PARTS LIST - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 7-1
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SPECIFICATIONS |
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Rated Power Consumption - - - - - - - - - - - - - - - - - |
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- - - - - - 1500W |
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Output |
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Microwave - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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- - - - - - 1000W (*IEC60705 Rating standard) |
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Adjustable 100W through 1000W, 10 steps |
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Convection - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
- - - - - - - - - - - |
- - - - - - 1500W |
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Combination - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
- - - - - - - - - - - |
- - - - - - 1500W |
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Frequency - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
- - - - - - - - - - - |
- - - - - - 2450 MHz |
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Power Supply - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
- - - - - - - - - - - |
- - - - - - 120 V AC, 60 Hz |
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Rated Current - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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- - - - - - 13 Amp. |
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Magnetron Cooling - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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- - - - - - Forced Air Cooling |
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Microwave Stirring - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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- - - - - - Turntable |
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Rectification - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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- - - - - - Rectification Voltage Doubler Half-Wave |
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Door Sealing - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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- - - - - - Choke Cover and Choke System |
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Safety Devices - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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- - - - - - Thermostat: |
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Open at 90°c ± 5°c |
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Close at 75°c ± 5°c |
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Fuse(20A) |
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Primary Interlock Switch |
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Secondary Interlock Switch |
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Interlock Monitor Switch |
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Magnetron - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
- - - - - - - - - - - |
- - - - - - 2M246 |
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High Voltage Capacitor - - - - - - - - - - - - - - - - - - - - - |
- - - - - - - - - - - |
- - - - - - Capacitor: 1.0 µF, 2.1 KV AC |
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High Voltage Diode - - - - - - - - - - - - - - - - - - - - - - - - - - |
- - - - - - - - - - - |
- - - - - - 350 mA, 9.0 KV |
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Cavity Lamp - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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- - - - - - 125 V, 20 W |
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Tray - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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- - - - - - Tempered Safety Glass |
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Overall Dimensions - - - - - - - - - - - - - - - - - - - - - - - - - - |
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- - - - - - 225/8"(W)x20"(H)x147/8"(D) |
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Oven Cavity Size - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
- - - - - - - - - - - |
- - - - - - 151/4"(W)x151/4"(H)x107/8"(D) |
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Effective Capacity of Oven Cavity - - - - - - |
- - - - - - - - - - - |
- - - - - - 1.5 Cu.ft. |
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Accessories - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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- - - - - - Use and Care Manual, Glass Turntable, |
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Rotating Ring, Metal Rack |
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SWITCH CHART |
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PRIMARY |
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SECONDARY |
INTERLOCK |
SWITCH MODE |
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INTERLOCK |
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INTERLOCK |
MONITOR |
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SWITCH |
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SWITCH |
SWITCH |
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CONDITIONS |
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NC |
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DOOR OPEN |
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DOOR CLOSED |
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NOTE: Use the above switch chart with circuit diagram on page 4-4. “•” represents the connection of the terminal of each switch.
1-1
CAUTIONS
Unlike other appliances, the microwave oven is high-voltage and high-current equipment. Though it is free from danger in ordinary use, extreme care should be taken during repair.
•DO NOT operate on a 2-wire extension cord during repair and use.
•NEVER TOUCH any oven components or wiring during operation.
•BEFORE TOUCHING any parts of the oven, always remove the power plug from the outlet.
•For about 30 seconds after the oven stops, an electric charge remains in the high voltage capacitor. When replacing or checking, you must discharge the high voltage capacitor by shorting across the two terminals with an insulated screwdriver.
•Remove your watches whenever working close to or replacing the Magnetron.
•DO NOT touch any parts of the control panel circuit. A resulting static electric discharge may damage this P.C.B.
•NEVER operate the oven with no load.
•NEVER injure the door seal and front plate of the oven cavity.
•NEVER put iron tools on the magnetron.
•NEVER put anything into the latch hole and the interlock switches area.
MICROWAVE RADIATION
Personnel should not be exposed to the microwave energy which may radiate from the magnetron or other microwave generating device if it is improperly used or connected. All input and output microwave connections, waveguide, flange, and gasket must be secured never operate the device without a microwave energy absorbing load attached. Never look into an open waveguide or antenna while the device is energized.
•Proper operation of the microwave oven requires that the magnetron be assembled to the waveguide and cavity. Never operate the magnetron unless it is properly installed.
•Be sure that the magnetron gasket is properly installed around the dome of the tube whenever installing the magnetron.
ANTENNA
GASKET
COOLING FIN
FILAMENT
TERMINALS
MAGNETRON
CHASSIS GROUND
MAGNETRON
THE OVEN IS TO BE SERVICED ONLY BY PROPERLY QUALIFIED SERVICE TECHNICIANS.
2-1
INSTALLATIONS
BEFORE YOU BEGIN, READ THE FOLLOWING INSTRUCTIONS COMPLETELY AND CAREFULLY.
INSTALLING
1.Empty the microwave oven and clean inside it with a soft, damp cloth. Check for damage such as misaligned door, damage around the door, dents inside the cavity, or on the exterior.
2.Put the oven on a counter, table, or shelf at least 39.4 inches(100cm) from floor that is strong enough to hold the oven and the food and utensils you put in it. (The control panel side of the oven is the heavy side. Use care when handling.)
3.Do not block the vent and the air intake openings. Blocking vent or air intake openings can cause damage to the oven and poor cooking results. Make sure the microwave oven legs are in place to ensure proper air flow.
4.The oven should not be installed in any area where heat and steam are generated, because they may damage the electronic or mechanical parts of the unit. Do not install the oven next to a conventional surface unit or above a conventional wall oven.
5.Use microwave oven in an ambient temperature less than 104°F(40°C).
6.Place the microwave oven on a sturdy and flat surface at least 2 inches(5 cm) from the wall.
7.Place the microwave oven as far away as possible from TV, RADIO, COMPUTER, TELEPHONE, etc., to prevent interference.
GROUNDING INSTRUCTIONS
For personal safety, this appliance must be fully grounded at all times.
In the event of an electrical short circuit, grounding reduces the risk of electrical shock.
The plug must be plugged into an outlet that is properly installed and grounded.
WARNING
Improper use of the grounding plug can result in a risk of electric shock.
Do not, under any circumstances, cut or remove the third ground prong from the power cord plug.
PREFERRED METHOD
ENSURE PROPER GROUND
EXISTS BEFORE USE
5cm
Counter, |
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3-1
OPERATING INSTRUCTIONS
FEATURES
Oven Front Plate
Window Door Screen
Door Seal
Metal Rack
Display Window
Control Panel
Glass Tray
Safety Interlock |
Rotating Ring |
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CONTROL PANEL
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1.DISPLAY. The Display includes a clock and indicators to tell you time of day, cooking time settings and cooking functions selected.
2.MICRO. Touch this pad when setting microwave cooking.
3.CONV. Touch this pad to operate the oven for convection cooking only.
4.COMBI. Touch this pad to program the amount roasting time and heat for a cooking cycle using both microwave energy and convection energy.
5.CONVECTION AUTO BAKE. Touch this pad to automatically bake frozen pizza, muffins, biscuits and frozen French fries using both microwave and convection energy alternately.
6.CONVECTION AUTO ROAST. Touch this pad to automatically roast beef, chicken, turkey breasts and pork using both microwave and convection energy alternately.
7.SENSOR COOK. Touch this pad to cook 10 types of foods. The oven's sensor will tell the oven how long to cook depending on the amount of humidity coming from the food.
8.SENSOR POPCORN. Touch this pad when popping commercially packaged popcorn in your microwave oven. The oven's sensor will tell the oven how long to cook depending on the amount of humidity it detects from the popcorn.
9.SENSOR REHEAT. Touch this pad to reheat precooked, room-temperature or refrigerated foods. The oven's sensor will tell the oven how long to cook depending on the amount of humidity coming from the food.
10.AUTO DEFROST. Touch this pad once to automatically defrost Meat, Poultry, Fish or Bread according to weight. Touch this pad twice to defrost most other frozen foods by time.
11.EXPRESS DEFROST. Touch this pad for rapid defrosting of one pound of frozen food.
12.WARM HOLD. Touch this pad to keep hot, cooked foods warm in your microwave oven.
13.MORE. Touch this pad to add 10 seconds of cooking time each time it is pressed.
14.LESS. Touch this pad to subtract ten seconds of cooking time each time it is pressed.
15.NUMBER. Touch number pads to enter cooking times, cook powers, quantities, weights, or food categories.
16.ADD MINUTE. Touch this pad to set and start cooking at 100% power.
17.POWER. Touch this pad to select a cooking power level.
18.STOP/CLEAR. Touch this pad to cancel a currently running program or erase a cooking cycle being programmed.
19.START/PAUSE. Touch this pad to start a program or to pause the oven during cooking or defrosting.
20.OPTION. Touch this pad to change the oven's default settings for volume, clock, scroll speed, units of weight and language.
21.CLOCK. Touch this pad to enter the time of day.
22.KITCHEN TIMER. Touch this pad to set the kitchen timer.
4-1
OPERATING SEQUENCE
The following is a description of component functions during oven operation.
1. SETTING THE CLOCK
Stop/ |
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Clock |
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Enter time |
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Start/Pause |
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Clear |
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of day |
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2.START/PAUSE and CANCEL FUNCTION
1)Touch Start/Pause pad to start oven or pause the oven temporarily during cooking.
2)Touch Clear pad to cancel a program during cooking or Erase during programming.
3.KITCHEN TIMER.
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Kitchen Timer |
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Enter time |
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Start/Pause |
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6.MORE / LESS
•The More and Less functions will adjust the cook time of many oven functions.
•More/Less will add/subtract 10 seconds to the cook time each time you press it.
NOTE:
•For convection cooking, More and Less are used as temperature selection pads.
7.MICRO COOKING
Micro 
Cooking time 
Power
Power 
Start/Pause
Level
4. CHILD LOCK |
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8. MULTI-STAGE COOKING |
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1ST STAGE |
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TO SET CHILD LOCK |
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• Touch and hold START/PAUSE pad |
Micro |
Cooking |
Power |
Enter Power |
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• Touch and hold START/PAUSE pad |
time |
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LOCKED appear on the display. |
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TO CANCEL CHILD LOCK |
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• Touch and hold START/PAUSE pad |
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LOCKED disappear in the display. |
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Cooking |
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time |
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5. WARM HOLD |
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Enter |
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Stop/ |
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Warm Hold |
Start/Pause |
Power Level |
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Clear |
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To keep hot, cooked food warm.
4-2
OPERATING SEQUENCE
9.SENSOR TOUCH COOKING
•Sensor cook and reheat
Stop/ |
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Sensor Cook |
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Select Sensor |
Clear |
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menu |
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Sensor Reheat |
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• Sensor Popcorn
Stop/ 
Popcorn
Clear
10. AUTO DEFROST
Stop/ |
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Clear |
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Defrost |
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category |
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Enter the |
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Start/Pause |
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Weight |
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Stop/ |
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Number |
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Clear |
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Defrost |
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Start/Pause |
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11. EXPRESS DEFROST
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Defrost |
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12. AUTO BAKE/ROAST
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TO PREHEAT |
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TO COOK(After preheating)
Cooking Time 
Start/Pause
14. COMBINATION
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Start/Pause
4-3
SCHEMATIC DIAGRAM
NOTE:
1.DOOR IS OPENED.
2.WIRE COLOR.
SYMBOL |
COLOR |
BN |
BROWN |
WH |
WHITE |
BK |
BLACK |
BL |
BLUE |
YL |
YELLOW |
PK |
PINK |
RD |
RED |
GN |
GREEN |
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4-4
CIRCUIT DESCRIPTION
GENERAL DETAILS
•The low voltage transformer supplies the necessary voltage to the micom controller when power cord is plugged in.
•When the door is closed, the primary switch is ON, the secondary switch is ON, and the monitor switch opens (contact COM and NO).
WHEN SELECTING COOKING POWER LEVEL AND TIME
•The micom controller memorizes the function you set.
•The time you set appears in the display window.
•Each indicator light turns on to indicate that the stage has been set.
WHEN TOUCHING THE START PAD
•The coil of the relay is energized by the micom controller.
•Power input is supplied to the high voltage transformer through the fuse to the primary switch and relay 2.
•Turntable rotates.
N |
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H.V. |
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MONITOR |
TRANS- |
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L |
SWITCH |
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FUSE |
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PRIMARY |
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SECONDARY |
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SWITCH RELAY 2 |
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SWITCH |
MICOM CONTROLLER
•The fan motor rotates and cools the magnetron by blowing the air.
•The air is also directed into the oven to exhaust the vapor in the oven through the upper plate.
•Cooking time starts counting down.
•3.15 volts AC is generated from the filament winding of the high voltage transformer. This 3.15 volts is applied to the magnetron to heat the magnetron filament through two noise-preventing choke coils.
•A high voltage of approximately 2,210 volts AC is generated in the secondary of the high voltage transformer which is increased by the action of the high voltage diode and charging of the high voltage capacitor.
•The negative 4,000 Volts DC is applied to the filament of the magnetron.
WHEN THE OVEN IS SET AT ANY LEVEL EXCEPT MAXIMUM.
•The micom controller controls the ON-OFF time of relay 2 by the applied signal to vary the average output power of microwave oven as POWER LEVEL. (refer to page 1-1)
•One complete cycle of relay 2 is 22 seconds.
WHEN THE DOOR IS OPENED DURING COOKING
•Both the primary switch and relay 2 cut off the primary winding voltage of the high voltage transformer.
•ON-OFF of relay 2 is coupled electrically with opening and closing of the secondary switch.
•When the door is opened, the secondary switch is opened and when the door is closed, the secondary switch is closed.
•The cooking time stops counting down.
•Relay stops functioning.
•As the door is opened, if the contact of primary switch and relay 2 and/or secondary switch fail to open, the fuse opens due to the large current surge caused by the monitor switch activation, which in turn stops magnetron oscillation.
N |
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H.V. |
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MONITOR |
TRANS- |
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FORMER |
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SWITCH |
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FUSE
PRIMARY |
SECONDARY |
SWITCH RELAY 2 |
SWITCH |
MICOM CONTROLLER
WHEN TOUCHING THE START KEY WITH THE CONVECTION COOKING.
•The contacts of the primary switch and the secondary switch close the circuit.
•Damper close.
•Turntable rotates.
•Fan Motor, Circulation Motor rotate.
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RELAY 4 |
N |
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G-Y |
E |
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CONVECTION |
L |
HEATER |
4-5
SERVICE INFORMATION
TOOLS AND MEASURING INSTRUMENTS
NECESSARY TOOLS
Tools normally used for TV servicing are sufficient. Tools needed for service are listed below.
•Diagonal pliers
•Long nose pliers
•Phillips screwdriver
•Flat blade screwdriver
•Wrench (size 2 inches(5mm))
•Nutdriver (size 2 inches(5mm))
•Adjustable wrench
•Soldering iron
•Solder
•Vinyl insulation tape
•Polishing cloth
NECESSARY MEASURING INSTRUMENTS
•TESTER (VOLTS-DC, AC, Ohm meter)
•Microwave survey meter
-Holaday HI-1500
HI-1501 - Narda 8100
8200
•Inch scale
•600 cups (cc) non conductive material beaker (glass or plastic), inside diameter: approx. 31/2 inches (8.5 cm)
•Cylindrical and made of borosilicate glass vessel. max. thickness: 0.12 inches (3mm)
outside diameter: approx. 7.5 inches (190mm) height: approx. 3.5 inches (90mm)
•Glass thermometer: 212°F (100°C) (1 deg scale)
MICROWAVE LEAKAGE TEST
CAUTIONS
•Be sure to check microwave leakage prior to servicing the oven if the oven is operative prior to servicing.
•The service personnel should inform the manufacture importer, or assembler of any certified oven unit found to have a microwave emission level in excess of 5 mW/cm2 and should repair any unit found to have excessive emission levels at no cost to the owner and should ascertain the cause of the excessive leakage. The service personnel should instruct the owner not to use the unit until the oven has been brought into compliance.
•If the oven operates with the door open, the service personnel should:
-Tell the user not to operate the oven.
-Contact the manufacturer.
•The service personnel should check all surface and vent openings for microwave leakage.
•Check for microwave leakage after every servicing. The power density of the microwave radiation leakage emitted by the microwave oven should not exceed
5 mW/cm2. Always start measuring of an unknown field to assure safety for operating personnel from radiation leakage.
MEASURING MICROWAVE ENERGY LEAKAGE
•Pour 275±15cc of 20±5°C(68±9°F) water in a beaker which is graduated to 600 cc, and place the beaker on the center of the turntable.
•Set the energy leakage monitor to 2,450 MHz and use it following the manufacturer's recommended test procedure to assure correct result.
•When measuring the leakage, always use the
2 inches (5cm) spacer supplied with the probe.
•Operate the oven at its maximum output.
•Measure the microwave radiation using and electromagnetic radiation monitor by holding the probe perpendicular to the surface being measured
Move probe along shaded area
Probe scanning speed Less than 2.5 cm/sec (1 in/sec)
5-1
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