Sharp R-480J Servicing, Troubleshooting Guide, Remember to Check 3D, Remember to Check 4R

Page 9

R-480J

SERVICING

WARNING TO SERVICE PERSONNEL

Microwave ovens contain circuitry capable of pro- ducing very high voltage and current, contact with any part of the high voltage circuit will result in electrocution. High voltage capacitor, Power trans- former, Magnetron, High voltage rectifier assem- bly, High voltage fuse, High voltage harness.

REMEMBER TO CHECK 3D

1)Disconnect the supply.

2)Door opened, and wedged open.

3)Discharge high voltage capacitor.

WARNING: AGAINST THE CHARGE OF THE HIGH-VOLTAGE CAPACITOR

The high-voltage capacitor remains charged about 60 seconds after the oven has been switched off. Wait for 60 seconds and then short-circuit the connection of the high-voltage capacitor (that is, of the connecting lead of the high-voltage rectifier) against the chassis with the use of an insulated screwdriver.

Sharp recommend that wherever possible fault-finding is carried out with the supply disconnected. It may, in some cases, be necessary to connect the supply after the outer case has been removed, in this event carry out 3D checks and then disconnect the leads to the primary of the power transformer. Ensure that these leads remain isolated from other components and the oven chassis. (Use insulation tape if necessary.) When the testing is completed carry out 3D checks and reconnect the leads to the primary of the power trans- former.

REMEMBER TO CHECK 4R

1)Reconnect all leads removed from components during testing.

2)Replace the outer case (cabinet).

3)Reconnect the supply.

4)Run the oven. Check all functions.

Microwave ovens should not be run empty. To test for the presence of microwave energy within a cavity, place a cup of cold water on the oven turntable, close the door and set the microwave timer for two (2) minutes. Set the power level to HIGH and push the START button. When the two minutes has elapsed (timer at zero) carefully check that the water is now hot. If the water remains cold carry out 3D checks and re- examine the connections to the component being tested.

When all service work is completed and the oven is fully assembled, the microwave power output should be checked and microwave leakage test should be carried out.

TROUBLESHOOTING GUIDE

When troubleshooting the microwave oven, it is helpful to

IMPORTANT: If the oven becomes inoperative because

follow the Sequence of Operation in performing the

of a blown fuse F10A in the 1st. latch

checks. Many of the possible causes of trouble will require

switch - 2nd. interlock relay - monitor switch

that a specific test be performed. These tests are given a

circuit, check the 1st. latch switch, 2nd.

procedure letter which will be found in the “Test Procedure

interlock relay and monitor switch before

“section.

replacing the fuse F10A.

7

Image 9
Contents Microwave Oven Model R-480J Table of Contents480J Microwave Oven Sharp Corporation OSAKA, Japan480J General Important InformationGeneral Information Product SpecificationsDescription This Appliance Must be EarthedTouch Control Panel Appearance ViewOFF Condition Operation SequenceMicrowave Cooking Condition Variable CookingPower Output Reduction Cooking SequenceSensor Instant Reheat Function of Important Components Servicing Troubleshooting GuideRemember to Check 3D Remember to Check 4RProblem Test Procedure Possible Cause Defective PartsTest Procedures Procedure Component Test Letter Magnetron TestMicrowave Output Power 1 litre water load Power Transformer Test Test Procedures Letter Component TestHigh Voltage Rectifier Assembly Test High Voltage Capacitor TestSwitch Test Procedure Component Test LetterNoise Filter Test Carry OUT 3D Checks Thermal CUT-OUT TestTouch Control Panel Assembly Test Blown Fuse F10A Carry OUT 3D ChecksHigh Voltage Fuse Test Relay Test KEY Unit TestOmif Carry OUT 3D Checks Steps Occurrence Cause or CorrectionAH Sensor Test Checking the initial sensor cooking conditionTesting Method for AH Sensor AND/OR Control Unit Test Procedures LetterChecking Control Unit Sensor Dummy Resistor CircuitIndicator Circuit Reset CircuitPower Source Circuit Synchronizing Signal CircuitLSI Signal coming from touch key Pin No Signal DescriptionSignal similar to P17 Power source voltage GND0VCommon data signal COM7 Common data signal COM8Common data signal COM6 Common data signal COM5Structure of Absolute Humidity Sensor Absolute Humidity Sensor CircuitTouch Control Panel Servicing Other PrecautionsShapes of Electronic Components Servicing of Touch Control PanelComponent Replacement and Adjustment Procedure Power Transformer RemovalOuter Case Removal HOW to RE-INSTALL the Turntable Motor Cover Positive Lock Connector NO-CASE Type RemovalMagnetron Removal Turntable Motor RemovalCPU Unit and Power Unit Control Panel Assembly RemovalInstallation Oven Lamp and Lamp Socket RemovalAfter adjustment, check the following Power Supply Cord ReplacementRear View Side ViewRE-INSTALL Door ReplacementRemoval View back side of door frameAfter any service, make sure of the following InstallationSealer Film Microwave Measurement Preparation for TestingRequirement Holaday HI Simpson 380MFigure O-1. Oven Schematic-OFF Condition High Voltage Components Figure S-1. Pictorial DiagramFigure S-2. Power unitl Circuit FigureS3.CPU UnitZD1 SP1 VRB RY2 CN CCN a CN D D10 RY1 RY3 TTMParts List Miscellaneous Packing and AccessoriesSCREWS, Nuts and Washers Not replaceable items84-21 Control Panel Parts Door Parts Miscellaneous Copyright 2004 by Sharp Corporation ALL Rights Reserved

R-480J specifications

The Sharp R-480J is a notable microwave oven that combines advanced technology with practical design, catering to both everyday cooking needs and more complex culinary tasks. This model is designed for consumers seeking reliability and efficiency in their kitchen appliances.

One of the standout features of the Sharp R-480J is its powerful 900-watt output. This high wattage allows for faster cooking times, making meal preparation a breeze. The microwave also offers multiple power levels, which provides the user with the flexibility to cook a variety of dishes. Whether you are reheating leftovers, defrosting meats, or cooking fresh vegetables, the R-480J delivers consistent and thorough results.

The microwave is equipped with a spacious interior, accommodating larger dishes with ease. Its turntable design ensures even cooking by allowing food to rotate during the cooking process. This feature minimizes cold spots in the food, ensuring that meals are heated uniformly.

User-friendliness is a key aspect of the Sharp R-480J. The appliance comes with an intuitive control panel featuring pre-programmed settings for common food items such as popcorn, pizza, and dinner plates, making it easy for users to select the right cooking time and power level with just a few button presses. Additionally, the digital display shows cooking times and power levels clearly, enhancing the overall cooking experience.

The R-480J also incorporates advanced sensor cooking technology. This innovative feature detects humidity levels emitted by food and adjusts cooking time accordingly. This means users can achieve perfect results without constantly monitoring the microwave, allowing for greater convenience and efficiency in daily cooking.

Moreover, the microwave's sleek and modern design fits well into various kitchen aesthetics. Its easy-to-clean surfaces minimize maintenance efforts, while the compact build allows it to be placed in smaller kitchens without taking up too much space.

In conclusion, the Sharp R-480J microwave oven stands out for its powerful performance, user-friendly features, and practical design. Its combination of high wattage, multiple power levels, and sensor cooking technology makes it a versatile appliance for any kitchen. Whether tackling daily meals or experimenting with new recipes, the R-480J is equipped to meet diverse cooking needs with ease and efficiency.