Inverter NN-T551CB, Service Manual

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6.3. One touch Auto sensor cooking NN-T591 NN-T571
Auto sensor cook is a revolutionary way to cook by microwave 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 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 humidity sensor element, senses the
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 the power select and time features. Please consult variable power microwave
cook book for procedures.
Explanation of the auto sensor cooking process
1. The shaded columns in figure 1 indicate when the humidity sensor heater is on.
2. During this 30 second period there is no microwave activity. When calculating the
T2 time by using the formula below, make sure this 30 seconds is subtracted from
the T0 time.
3. T1 time = T0 time - 30 seconds.
4. T2 time. When the steam escapes from the cooking container placed in the oven,
the humidity sensor detects it and the microprocessor calculates the balance of
cooking time. This T2 time is then shown in the display and begins counting down.
Balance of cooking (T2 time)
The balance of cooking time which is called T2 time, can be calculated by the
following formula.
T2 time (in sec.) = T1 time x K factor
NOTE: Remember, the T1 time starts after the start pad is tapped. The coefficient K is
programmed into the microprocessor memory and they are listed in the following
tables along with the P1 and P2 powe r.
NOTE: When “More” or “Less” pad is selected, the K factor varies resulting in T2
time to be increased or decreased.
Calculating the T2 time
Example 1: If the T1 time is measured to be 2 minutes and 40 seconds, and the auto
sensor program is selected to sensor reheat. Fresh Fish (Program 3)
T2 = T1 x K
= 2 min 40 sec. X. 0.1
= 16 sec.