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

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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 Ω

approximately 1.2 Ω

b. Secondary winding

approximately 75 Ω

approximately 75 Ω

c. Filament winding

less than 1 Ω

 

 

 

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 kΩ in 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 10MΩ after it has been charged.

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

E.An open capacitor constantly shows a resistance about 10 MΩ because of its internal 10MΩ resistance.

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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Contents Commercial Microwave Oven Table of ContentsRemember to Check 4R Remember to Check 3DCommercial Microwave Oven Sharp Corporation OSAKA, Japan22AT/ R-24AT General Important InformationDescription SpecificationThis Appliance Must be Earthed Brown LiveDisplay and Indicators Installation InformationAppearance View Auto Touch Control PanelIdle Condition Operation SequenceMicrowave Cooking Condition Microwave Variable CookingFigure B-1. High Voltage Circuit TWO Magnetron Operation SystemFunction of Important Components Troubleshooting Guide EEP ROM KEY Unit Touch Control Transformer T3 Possible Cause and Defective PartsProcedure Letter Component Test Magnetron Test Test ProceduresMicrowave Output Power 1 litre water load Power Test Procedures Letter Component TestMicrowave Output Power 2000 cc alternative method Switch Test High Voltage Rectifier Assembly Test Carry OUT 3D ChecksCarry OUT 4R Checks Carry OUT 4R ChecksTemperature Fuse TF1, TF2, TF3 Test Procedure Letter Component TestWeak Point F3 Test Carry OUT 3D Checks Fuse F1, F2 F10A Test Carry OUT 3D ChecksMotor Winding Test Touch Control Panel Assembly TestNoise Filter Test High Voltage Fuse F4, F5 Test Carry OUT 3D ChecksRelay Test KEY Unit TestRY1 RY3Occurrence Cause or Correction Touch Control Panel Assembly LSIIXA222DR Description of LSISignal synchronized with commercial power source frequency Signal to sound buzzerInternal clock oscillation frequency setting input Power source voltageKey strobe signal Digit selection signalSound Voltage level control terminal Shapes of Electronic Components ServicingServicing of Touch Control Panel Servicing Tools Other PrecautionsPAD Order Display Phone Other Checking and Clearing PROCE- Dure for Procedure for Entering toDefrost SET Number Double Quantity Check Signal Precautions for Using LEAD-FREE SolderUsing lead-free wire solder Employing lead-free solderOuter CASE, Rear Cabinet and Power Supply Cord Removal Component Replacement and Adjustment ProcedureHigh Voltage Transformers Removal Re-install Magnetron Thermistor ReplacementMagnetrons Removal RemovalTerminal Insulator Replacement HOW to Release the Positive Lock ConnectorBlower Motor Removal Stirrer Motors Upper and Lower RemovalPower Supply Cord Replacement Control Panel Assembly and Control Unit RemovalControl Panel Assembly Removal HOW to Attach Membrane Switch and Graphic SheetAfter adjustment, make sure of the following Door Replacement and AdjustmentRemoval Choke Cover Removal Door DisassemblyDoor Components Removal Upper and Lower Latch Heads Removal Service InformationDoor Case Removal Door Glass RemovalMicrowave Measurement ProcedurePreparation Figure O-1 Oven Schematic-OFF Condition Figure O-3 Oven Schematic-Cooking Condition Figure S-1. Pictrorial Diagram DG1 PanelCircuitFigure S-3. Printed Wiring Board Parts marked * are used in voltage more than Parts ListElectoric Parts Cabinet PartsRH-IXA222DRZZ LSI RH-IXA298DRZZ Eeprom Oven PartsMiscellaneous Door PartsSCRE,NUTS and Washers Packing and Accessories HOW to Order Replacement PartsModel Number 2. REF. no Description Oven and Cabinet Parts Control Panel Parts Door Parts Miscellaneous
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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.
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