Panasonic NN-K153WF Service Manual page 28

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
POWER POWER(
SETTING
APPROX.
HIGH 100%
MEDIUM-HIGH
MEDIUM
MEDIUM-LOW
LOW
DEFROST
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
POWER POWER(
SETTING
APPROX.
HIGH 100%
MEDIUM-HIGH
MEDIUM
MEDIUM-LOW
LOW
DEFROST
6.3. Turbo defrost, Auto reheat, Auto cook control
ON-OFF TIME OF
POWER RELAY B (RY1)
%)
ON(SEC)
22
70% 17
50% 13
30% 8
15% 5
30% 8
ON-OFF TIME OF
POWER RELAY B (RY1)
%)
ON(SEC)
30
70% 23.5
55% 16.5
30% 9.0
10% 5
30% 9.0
OFF(SEC)
0
5
9
14
17
14
OFF(SEC)
0
6.5
13.5
21.0
25
21.0
10