Sharp R-3A54 - MICROWAVE OUTPUT POWER (1 LITRE WATER LOAD)

R-3A54
R-3E54
TEST PROCEDURES (CONT’D)
PROCEDURE
LETTER
COMPONENT TEST
CAUTION: 1 “C CORRESPONDS TO 65 WATTS.
REPEAT MEASUREMENT IF THE POWER IS INSUFFICIENT.
(Tl “C)
(T2 W
(T2 OC,*
Heat up for 2min. 8 sec.
MICROWAVE OUTPUT POWER (1 LITRE WATER LOAD)
(RD82A02J)
The following test procedure should be carried out with the microwave oven in a fully assembled
condition (outer case fitted). Microwave output power from the magnetron can be measured by
way of IEC 705, i.e. it can be measured by using water load how much it can be absorbed by the
water load. To measure the microwave output power in the microwave oven, the relation of cal-
orie and watt is used. When P(W) heating works for t(second), approximately P x t/4.1 87 calorie
is generated. On the other hand, if the temperature of the water with V(ml) rises AT (“C) during
this microwave heating period, the calorie of the water is V x AT.
The formula is as follows;
Pxt/4.‘l87=VxAT P(W)=4.187xVxAT/t
I Our condition for the water load is as follows:
Room temperature... . . . . . . . . . . . . . . . . . . around
20°C
Power supply Voltage . . . . . . . . . . . . . Rated
voltage
Water load . . . . . . . . 1000
g
Initial temperature . . . . . . . 10+2”C
Heating time . . . . . . . . . . . . . . . . 52 sec.
P=80xAT
Measuring condition:
1. Container
The water container must be a cylindrical borosilicate glass vessel having a maximum material
thickness of 3 mm and an outside diameter of approximately 190 mm.
2. Temperature of the oven and vessel
The oven and the empty vessel are at ambient temperature prior to the start of the test.
3. Temperature of the water
The initial temperature of the water is (10 + 2)“C.
4. Select the initial and final water temperature so that the maximum difference between the final
water temperature and the ambient temperature is 5K.
5. Select stirring devices and measuring instruments in order to minimize addition or removal of
heat.
6. The graduation of the thermometer must be scaled by O.l”C at minimum and an accurate
thermometer.
7. The water load must be (1000 f. 5) g.
8. “t” is measured while the microwave generator is operating at full power. Magnetron filament
heat-up time is not included.
NOTE: The operation time of the microwave oven is “t + 2” sec. 2 sec. is magnetron filament
heat-up time.
Measuring method:
1. Measure the initial temperature of the water before the water is added to the vessel.
(Example: The initial temperature Tl, = 11 “C)
2. Add the 1 litre water to the vessel.
3. Place the load on the centre of the shelf.
,
4. Operate the microwave oven at HIGH for the temperature of the water rises by a value A T of
10 + 2°C
5. Stir the water to equalize temperature throughout the vessel.
6. Measure the final water temperature. (Example: The final temperature T2 = 21 “C)
7. Calculate the microwave power output P in watts from above formula.
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