R-22AT

R-24AT

 

TEST PROCEDURES

PROCEDURE

 

LETTER

COMPONENT TEST

AMAGNETRON TEST

NEVER TOUCH ANY PART IN THE CIRCUIT WITH YOUR HAND OR AN INSULATED TOOL WHILE THE OVEN IS IN OPERATION.

CARRY OUT 3D CHECKS.

Isolate the magnetron from high voltage circuit by removing all leads connected to filament terminal.

To test for an open circuit filament use an ohmmeter to make a continuity test between the magnetron filament terminals, the meter should show a reading of less than 1 ohm.

To test for short circuit filament to anode condition, connect ohmmeter between one of the filament terminals and the case of the magnetron (ground). This test should be indicated an infinite resistance. If a low or zero resistance reading is obtained then the magnetron should be replaced.

MICROWAVE OUTPUT POWER (1 litre water load)

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 60705, i.e. it is measured by how much power the water load can absorb. To measure the microwave output power in the microwave oven, the relation of calorie and watt is used. When P(W) heating works for t(second), approximately P x t/4.187 calorie is generated. On the other hand, if the temperature of the water with V(ml) rises T (°C) during this microwave heating period, the calorie of the water is V x T.

The formula is as follows;

 

 

 

 

 

P x t / 4.187 = V x T+ 0.55 x mc (T2-T0)

P (W) = 4.187 x V x T / t + 0.55 x mc (T2-T0)/t

Our condition for water load is as follows:

 

 

 

Room temperature (T0)

......

around 20°C

Power supply Voltage

Rated voltage

Water load

1000 g

Initial temperature (T1)

10±1°C

Heating time

28 sec. [R-22AT] / 22sec. [R-24AT] Mass of container (mc)

..... 330 g

T2

Final Temperature

P = 150 x T [R-22AT] / P = 190 x T [R-24AT]

 

 

 

 

 

 

 

 

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 the test.

3.Temperature of the water

The initial temperature of the water is (10±1)°C.

4.Select the initial and final water temperature so that the maximum difference between the final water temperature and the ambient temperature is 5°C.

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 0.1°C at minimum and be an accurate thermometer.

7.The water load must be (1000±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 + 3” sec. (3 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 T1 = 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 until the temperature of the water rises by a value T of (10 ± 2) K.

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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Sharp R-22AT Test Procedures, Procedure Letter Component Test Magnetron Test, Microwave Output Power 1 litre water load

R-22AT, R-24AT specifications

The Sharp R-24AT and R-22AT microwave ovens are advanced kitchen appliances designed to enhance cooking convenience, efficiency, and versatility. Both models incorporate innovative technologies and features that cater to modern cooking needs.

The Sharp R-24AT boasts a robust 900 watts of cooking power, enabling users to prepare a wide variety of meals quickly and effectively. Its spacious 24-liter capacity is suitable for families and those who enjoy entertaining. One of the standout features of the R-24AT is its intelligent sensor technology, which automatically detects humidity levels in the cooking food. This innovative feature ensures optimal cooking times and temperatures, resulting in perfectly cooked dishes without the guesswork.

Another key technology in the R-24AT is the inverter cooking system. This system provides a seamless flow of power throughout the cooking process, allowing for more precise temperature control. Unlike traditional microwaves that operate in full power or off, inverter technology ensures consistent heat, which is particularly beneficial for tasks such as defrosting, reheating, and simmering.

The Sharp R-22AT, while slightly more compact with a 22-liter capacity, also delivers impressive performance with 800 watts of power. It features a similar inverter cooking system that guarantees even cooking results. Both models come with multiple auto-cook presets, providing users with a selection of quick options for common dishes such as popcorn, pizza, and oatmeal. This feature streamlines meal preparation and reduces the time spent on planning meals.

In addition, the user-friendly control panel on both models includes a combination of push-button and rotary dial controls for easy navigation. The inclusion of a bright LED display further enhances usability, allowing cooks to monitor cooking times and settings easily.

Safety is another critical aspect of the Sharp R-24AT and R-22AT. Both models come equipped with a child lock feature, ensuring peace of mind in homes with young children. The stainless steel interiors of these microwaves facilitate easy cleaning, while their sleek design adds a modern touch to any kitchen.

In summary, the Sharp R-24AT and R-22AT microwave ovens stand out for their advanced cooking technologies, user-friendly features, and thoughtful design. They empower home cooks to prepare meals with precision and ease, making them a valuable addition to any kitchen.