R-22AT

R-24AT

 

TEST PROCEDURES

PROCEDURE

 

LETTER

COMPONENT TEST

BHIGH VOLTAGE TRANSFORMER TEST

WARNING: High voltage and large currents are present at the secondary winding and filament winding of the high voltage transformer. It is very dangerous to work near this part when the oven is on. NEVER make any voltage measurements of the high-voltage circuits, including the magnetron filament.

CARRY OUT 3D CHECKS.

Disconnect the leads to the primary winding of the high voltage transformer. Disconnect the filament and secondary winding connections from the rest of the HV circuitry. Using an ohmmeter, set on a low range, it is possible to check the continuity of all three windings. The following readings should be obtained:

 

R-22AT

R-24AT

 

 

 

a. Primary winding

approximately 1.8

approximately 1.2

b. Secondary winding

approximately 75

approximately 75

c. Filament winding

less than 1

 

 

 

If the readings obtained are not stated as above, then the high voltage transformer is probably faulty and should be replaced.

CARRY OUT 4R CHECKS.

CHIGH VOLTAGE RECTIFIER ASSEMBLY TEST CARRY OUT 3D CHECKS.

Isolate the high voltage rectifier assembly from the HV circuit. The high voltage rectifier can be tested using an ohmmeter set to its highest range. Connect the ohmmeter across the terminal B+C of the high voltage rectifier and note the reading obtained. Reverse the meter leads and note this second reading. The normal resistance is infinite in one direction and more than 100 kin the other direction.

CARRY OUT 4R CHECKS.

B

 

 

C

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

HIGH VOLTAGE RECTIFIER

NOTE: FOR MEASUREMENT OF THE RESISTANCE OF THE RECTIFIER, THE BATTERIES OF THE MEASURING INSTRUMENT MUST HAVE A VOLTAGE AT LEAST 6 VOLTS, BE- CAUSE OTHERWISE AN INFINITE RESISTANCE MIGHT BE SHOWN IN BOTH DIREC- TIONS.

DHIGH VOLTAGE CAPACITOR TEST CARRY OUT 3D CHECKS.

A.Isolate the high voltage capacitor from the circuit.

B.Continuity check must be carried out with measuring instrument which is set to the highest resistance range.

C.A normal capacitor shows continuity for a short time (kick) and then a resistance of about 10Mafter it has been charged.

D.A short-circuited capacitor shows continuity all the time.

E.An open capacitor constantly shows a resistance about 10 Mbecause of its internal 10Mresistance.

F.When the internal wire is opened in the high voltage capacitor shows an infinite resistance.

G.The resistance across all the terminals and the chassis must be infinite when the capacitor is normal.

If incorrect reading are obtained, the high voltage capacitor must be replaced.

CARRY OUT 4R CHECKS.

ESWITCH TEST

CARRY OUT 3D CHECKS.

Isolate the switch to be tested and using an ohmmeter check between the terminals as described in the following table.

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Sharp R-22AT, R-24AT Carry OUT 4R Checks, High Voltage Rectifier Assembly Test Carry OUT 3D Checks, Switch Test

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.