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MEASUREMENT OF THE MICROWAVE OUTPUT POWER
Microwave output power can be checked by indirectly measuring the temperature rise of a certain amount
of water exposed to the microwave as directed below.
1) Microwave power output measurement is made with the microwave oven supplied at rated voltage and
operated at its maximum microwave power setting with a load of 1,000±5cc of potable water.
2) The water is contained in a cylindrical borosilicate glass vessel having a maximum material thickness of
3 mm and an outside diameter of approximately 190mm.
3) The oven and the empty vessel are at ambient temperature prior to the start of the test.
The initial temperature of the water is 10±2°C (50±3.6°F).
It is measured immediately before the water is added to the vessel. After addition of the water to the
vessel, the load is immediately placed on the center of the shelf which is in the lowest normal position
(Fig. 1)
4) Microwave power is switched on.
5) Heating time should be exactly 44 seconds.
Heating time is measured while the microwave generator is operating at full power.
The filament heat-up time for magnetrons is not included.
6) The initial and final water temperatures are selected so that the maximum difference between the
ambient and final water temperatures is 5K.
7) The microwave power output P in watts is calculated from the following formula:
P = 4187 X
T/t
•
T is actual temperature rise.
• t is the heating time.
The power measured should be 900W±10%.
CAUTION:
1. Water load should be measured exactly to 1 liters.
2. Input power voltage should be exactly 220 volts as specified.
3. Ambient temperature should be 20±2°C (68±3.6°F)
MICROWAVE EMISSION TEST
WARNING
Make sure to check the microwave leakage before and after or adjustment.
• Always, start measuring of an unknow field to assure. Safety for operating personnel from microwave
energy.
• Do not place your hands into any suspected microwave radiation field unless the safe density level is
known.
• Care should be taken not to place the eyes in direct line with the source of microwave energy.
PROCEDURE
A) Prepare Microwave Energy Survey Meter, 600cc glass breaker, glass thermometer 100°C or 212°F.
B) Pour 275cc±15cc of tap water initially at 20±5°C (68±9°F) in the 600cc beaker with an inside diameter
of approx. 8.5 cm (3.5 in).
C) Place it at the center of the tray and set it in a cavity.
D) Close the door and operate the oven.
18
Fig.1
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