16
5. Alignment and Adjustments
5-8 Output Power of Magnetron
MICROWAVE RADIATION
PERSONNEL SHOULD NOT ALLOW EXPOSURE TO MICROWAVE RADIATION FROM MICROWAVE
GENERATOR OR OTHER PARTS CONDUCTING MICROWAVE ENERGY.
The output power of the magnetron can be measured by performing a water temperature rise test.
Equipment needed :
•
Two 1-liter cylindrical borosilicate glass vessel (Outside diameter 190 mm)
•
One glass thermometer with mercury column
NOTE:
Check line voltage under load. Low voltage will lower the magnetron output. Make all temperature and
time tests with accurate equipment.
1.
Fill the one liter glass vessel with water.
2.
Stir water in glass vessel with thermometer, and record glass vessel’s temperature (“T1”, 10±1°C).
3.
After moving the water into another glass vessel, place it in the center of the cooking tray. Set the oven to high
power and operate for 50 seconds exactly. (3 seconds included as a holding time of magnetron oscillation:)
4.
When heating is finished, stir the water again with the thermometer and measure the temperature (“T2”).
5.
Subtract T1 from T2. This will give you the water temperature rise. (∆T)
6.
The output power is obtained by the following formula;
Output Power =
4.187 x 1000 x ∆T+0.55xMcx(T2 -T1)
50
: Heating Time (sec)
47
: Counting Time (sec)
4.187 : Coefficient for Water
1000 : Water (cc)
∆T
: Temperature Rise (T2-T1)
To
: Room Temperature
Mc
: Cylindrical borosilicate glass weight
47
7.
Normal temperature rise for this model is 9°C to 11°C at ‘HIGH’.
NOTE
1: Variations or errors in the test procedure will cause a variance in the temperature rise. Additional power
test should be made if temperature rise is marginal.
NOTE
2: Output power in watts is computed by multiplying the temperature rise (step 5) by a factor of 91 times the
of centigrade temperature.
