2 DESCRIPTION OF OPERATING SEQUENCE
2.1.Variable power cooking control
High Voltage Inverter Power Supply (U) controls output power by the signal from Digital Programmer Circuit (DPC). Power relay always stay on, but PWM (Pulse Width Modulation) signal controls microwave output power.
NOTE:
The ON/OFF time ratio does not correspond with the percentage of microwave power since approximately 2 seconds are required for heating of magnetron filament.
Variable Power Cooking
POWER SETTING | OUTPUT | MANUAL MICROWAVE | ||
|
| POWER(%) | DUTY | |
|
| APPROX. | ON(SEC) | OFF(SEC) |
HIGH | P10 | 100% | 22 | 0 |
| P9 | 90% | 22 | 0 |
| P8 | 80% | 22 | 0 |
P7 | 70% | 22 | 0 | |
MEDIUM | P6 | 60% | 22 | 0 |
| P5 | 50% | 22 | 0 |
| P4 | 40% | 22 | 0 |
P3 | 30% | 22 | 0 | |
| P2 | 20% | 15 | 7 |
| P1 | 10% | 8 | 14 |
DEFROST | P3 | 30% | 22 | 0 |
2.2.Inverter power supply circuit
The Inverter Power Supply circuit powered from the line voltage, 120V 60Hz AC input supplies 4,000V DC to the magnetron tube, and functions in place ofthe H.V. transformer, the H.V. capacitor and H.V. diode.
1.The AC input voltage 120V 60Hz is rectified to DC voltage immediately.
2.DC voltage will be supplied to the switching devices called IGBT. These devices are switched
3.This drives the High voltage transformer to increase voltage up to 2,000V AC.
4.Then the
5.Output power of the magnetron tube is always monitored by the signal output from the current transformer built into the inverter circuit.
6.This signal is fed back to the microcomputer in the DPC to determine operating conditions and output necessary to control PWM signal to the Inverter Power Supply for control of the output power.
2.3.Inverter defrost
When the Auto Control feature is selected and the Start pad is tapped:
1.The digital programer circuit determines the power level and cooking time to complete cooking and indicates the operating state in the display window. Table shows the corresponding cooking times for respective serving by categories.
Inverter Turbo Defrost
SELECTED WEIGHT | COOKING TIME |
1.0 LB | 5 min.00 sec. |
2.When cooking time in the display window has elapsed, the oven turns off automatically by a control signal from the digital programmer circuit.
2.4.Sensor cooking
Auto sensor cooking without setting a power level or selecting a time. All that is necessary is to select an Auto Sensor Program before starting to cook.
Understanding Auto Sensor Cooking
As the food cooks, a certain amount of steam is produced. If the food is covered, this steam builds up and eventually escapes from the container. In Auto Sensor Cooking, a carefully designed instrument, called the steam sensor element, senses this escape of steam. Then, based upon the Auto Sensor Program selected, the unit will automatically determine the correct power level and the proper length of time it will take to cook the food.
NOTE:
Auto Sensor Cooking is successful with the foods and recipes found in the Auto Sensor Cooking Guide. Because of the vast differences in food composition, items not mentioned in the Cooking Guide should be prepared in the microwave oven using power select and time features. Please consult Variable Power Microwave Cookbook for procedures.
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