Panasonic NN-K153WF, Service Manual

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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
OUTPUT ON-OFF TIME OF
POWER
SETTING
POWER(
%)
POWER RELAY B (RY1)
APPROX. ON(SEC) OFF(SEC)
HIGH 100% 22 0
MEDIUM-HIGH 70% 17 5
MEDIUM 50% 13 9
MEDIUM-LOW 30% 8 14
LOW 15% 5 17
DEFROST 30% 8 14
6.2. Variable power cooking control (NN-K102WF)
The vari-power controller controls the ON-OFF time of the vari-power switch to vary the output
power of the microwave oven from “Low” to “High”. The vari-power controller is a part of the
timer assembly. The timer assembly consists of timer motor, timer switch, vari-power switch
and the combination of gears, cam and actuater level.
One complete cycle of the vari-power controller is 30 senconds, in which the vari-power switch
is turned “ON” or “OFF” by the cam rotation in the 30 ± 2 second period.
By controlling the timing of the vari-power switch “ON” period, the 230 - 240V AC supplied to
the high voltage transformer is interrupted intermittently so that the average output power of
the microwave oven is varied.
Table shows the timing chart of vari-power switch operation in response to the power setting on
the control panel.
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
OUTPUT ON-OFF TIME OF
POWER
SETTING
POWER(
%)
POWER RELAY B (RY1)
APPROX. ON(SEC) OFF(SEC)
HIGH 100% 30 0
MEDIUM-HIGH 70% 23.5 6.5
MEDIUM 55% 16.5 13.5
MEDIUM-LOW 30% 9.0 21.0
LOW 10% 5 25
DEFROST 30% 9.0 21.0
6.3. Turbo defrost, Auto reheat, Auto cook control
10