Sharp R-2397 service manual Shapes of Electronic Components, Servicing of Touch Control Panel

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R-2397

Pin No.

Signal

I/O

Description

1-3

A0-A2

IN

Connected to GND.

4

VSS

IN

Connected to VC(-5V).

5

SDA

IN/OUT

Serial data input/output : input/outputs data to IC1.

6

SCL

IN

Clock signal input : input/outputs sireal data at every one pulse.

7

TEST

IN

Connected to VC(-5V).

8

VCC

IN

Connected to GND.

SERVICING

1.Precautions for Handling Electronic Components This unit uses CMOS LSI in the integral part of the circuits. When handling these parts, the following pre- cautions should be strictly followed. CMOS LSI have extremely high impedance at its input and output termi- nals. For this reason, it is easily influenced by the surrounding high voltage power source, static electricity charge in clothes, etc, and sometimes it is not fully protected by the built-in protection circuit.

In order to protect CMOS LSI.

1)When storing and transporting, thoroughly wrap them in aluminium foil. Also wrap all PW boards containing them in aluminium foil.

2)When soldering, ground the technician as shown in the figure and use grounded soldering iron and work table.

approx. 1M ohm

2. Shapes of Electronic Components

Transistor

Transistor

 

 

Transistor

2SB953

2SA1561

 

 

DTA114YS

 

2SB1238

 

 

DTB143ES

E C B

E C B

 

 

DTD143ES

E

C

B KRA101M

 

 

 

 

 

 

 

3.Servicing of Touch Control Panel

We describe the procedures to permit servicing of the touch control panel of the microwave oven and the precautions you must take when doing so. To perform

the servicing, power to the touch control panel is avail- able either from the power line of the oven itself or from an external power source.

(1)Servicing the touch control panel with power supply of the oven:

CAUTION: THE HIGH VOLTAGE TRANSFORMER OF THE MICROWAVE OVEN IS STILL LIVE DURING SERVICING PRESENTS A HAZ- ARD.

Therefore, when checking the performance of the touch control panel, put the outer cabinet on the oven to avoid touching the high voltage transformer, or unplug the primary terminal (connector) of the high voltage trans- former to turn it off; the end of such connector must be insulated with an insulating tape. After servicing, be sure to replace the leads to their original locations.

A. On some models, the power supply cord between the touch control panel and the oven itself is so short that the two can’t be separated. For those models, check and

repair all the controls (sensor-related ones included) of the touch control panel while keeping it connected to the oven.

B. On some models, the power supply cord between the touch control panel and the oven proper is long enough that they may be separated from each other. For those models, therefore, it is possible to check and repair the controls of the touch control panel while keeping it apart from the oven proper; in this case you must short both ends of the door sensing switch (on PWB) of the touch control panel with a jumper, which brings about an operational state that is equivalent to the oven door being closed. As for the sensor-related controls of the touch control panel, checking them is possible if dummy resistor(s) with resistance equal to that of the controls are used.

(2)Servicing the touch control panel with power supply from an external power source:

Disconnect the touch control panel completely from the oven proper, and short both ends of the door sensing switch (on PWB) of the touch control panel, which brings about an operational state that is equivalent to the oven door being closed. Connect an external power source to the power input terminal of the touch control panel, then it is possible to check and repair the controls of the touch control panel it is also possible to check the sensor- related controls of the touch control panel by using the dummy resistor(s).

4.Servicing Tools

Tools required to service the touch control panel assem- bly.

1) Soldering iron: 30W

(It is recommended to use a soldering iron with a grounding terminal.)

2)Oscilloscope: Single beam, frequency range: DC-10MHz type or more advanced model.

3)Others: Hand tools

5. Other Precautions

1)Before turning on the power source of the control unit, remove the aluminium foil applied for preventing static electricity.

2)Connect the connector of the key unit to the control unit being sure that the lead wires are not twisted.

3)After aluminium foil is removed, be careful that abnormal voltage due to static electricity etc. is not applied to the input or output terminals.

4)Attach connectors, electrolytic capacitors, etc. to PWB, making sure that all connections are tight.

5)Be sure to use specified components where high preci- sion is required.

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Contents Commercial Microwave Oven Table of Contents2397 General Important Information Sharp Corporation OSAKA, JapanCommercial 2397Description SpecificationProduct Description General InformationOperating Keys Installation InformationDisplay and Indicators Appearance ViewMicrowave Variable Cooking Operation SequenceOFF Condition Microwave Cooking ConditionFunction of Important Components Magnetron Thermistor Asymmetric RectifierExhaust Thermistor Intake ThermistorRemember to Check 4R Troubleshooting GuideServicing Remember to Check 3DPlugged into wall outlet Test Procedure Possible Cause Defective PartsTemperature of Intake Thermistor is High Around 20 C Power supply Voltage Rated voltage Test ProceduresProcedure Component Test Letter Magnetron Test Microwave Output Power IEC-705-1988Carry OUT 4R Checks Procedure Letter Component TestHigh Voltage Transformer Test Carry OUT 3D ChecksWeak Point A018 Procedure Component Test LetterSwitch Test High Voltage Capacitor Test Carry OUT 3D ChecksMonitor Resistor Test Carry OUT 3D Checks Fuse F6.3A TestThermal CUT-OUT Test Carry OUT 3D Checks Table Thermal Cut-out TestMotor Winding Test Procedure Component Test Letter Magnetron Thermistor TestExhaust Thermistor Test Intake Thermistor TestKEY Unit Test Touch Control Panel Assembly TestMin Cx ± 20% Cy ± 20% 5mH Circuity Test Procedures ContdTo determine if the control unit or key pad is at fault Relay TestExhaust Air Temperature Detecting Circuit Power Supply CircuitPower Sync Signal Generating Circuit Stop Switch CircuitDescription of LSI LSIIZA646DR Signal coming from touch key Pin No Signal DescriptionInternal clock oscillation frequency setting input Power source voltageSound Voltage level control terminal Servicing of Touch Control Panel Other PrecautionsServicing Shapes of Electronic ComponentsPractice for checking total service counts eg 234,567 Counts Procedure for Entering to IC-2Other Checking and Clearing PRO Cedure To check the contents of defrost Flicker / 0.1 sec BuzzerTo remove the components, proceed as follows Component Replacement and Adjustment ProcedureOuter Case Removal High Voltage Components RemovalStirrer Motor Upper Removal Magnetron RemovalHigh Voltage Transformer Removal Blower Motor RemovalProcedure Control Panel Assembly and Control Unit RemovalHOW to Release the Positive Lock Connector Control Panel Assembly RemovalAfter adjustment, make sure of the following Power Supply Cord ReplacementRe-install Choke Cover Removal Door Replacement and AdjustmentDoor Replacement Door AdjustmentRequirement Service InformationPreparation for Testing Microwave MeasurementFigure O-1. Oven SChematic-OFF Condition High Voltage Components C d e CircuitFigure S-3. Printed Wiring Board Cabinet Parts Parts ListParts marked * are used in voltage more than Electric PartsVCEAB31HW104M Door Parts Oven PartsSCRE, Nuts and Washers MiscellaneousDescription HOW to Order Replacement PartsModel Number REF. noOven and Cabinet Parts Control Panel Parts Door Parts Not replaceable items 2397

R-2397 specifications

The Sharp R-2397 is a high-performance microwave oven that combines advanced technology with user-friendly features, making it a popular choice for modern kitchens. This model stands out due to its sleek design and efficient functionality, catering to both cooking enthusiasts and busy households alike.

One of the most notable features of the Sharp R-2397 is its powerful microwave cooking capabilities. With a wattage rating of 900 watts, it ensures that food is cooked evenly and quickly, allowing users to prepare meals in a fraction of the time compared to conventional ovens. The unit also offers multiple power levels, enabling precise cooking adjustments for various types of food, from defrosting to reheating and everything in between.

Another key characteristic of the R-2397 is its spacious interior. With a generous capacity of 23 liters, this microwave can accommodate larger dishes, making it suitable for families or individuals who enjoy hosting gatherings. The turntable feature promotes even cooking by rotating food continuously, ensuring that every inch is heated uniformly.

Additionally, the Sharp R-2397 is equipped with a range of convenient presets and auto-cook functions. These pre-programmed settings allow users to optimize cooking times for common dishes, such as popcorn, vegetables, and frozen meals, simplifying meal preparation and enhancing user experience. The intuitive control panel is designed to be user-friendly, ensuring that anyone can operate the microwave with ease.

Safety is also a significant consideration in the design of the Sharp R-2397. The unit comes with a child lock function, preventing accidental operation and ensuring that the oven is used safely in households with young children. This feature adds peace of mind for parents while using the appliance in their daily routines.

Moreover, the R-2397 incorporates a modern aesthetic that can fit into various kitchen styles. Its polished exterior and compact design make it both attractive and practical, with the added advantage of easy cleaning and maintenance.

In summary, the Sharp R-2397 is a versatile microwave oven that offers a blend of power, efficiency, and user-centric features. With its high wattage, spacious interior, smart presets, and safety measures, it is an excellent addition to any kitchen, catering to everyday cooking needs and helping to simplify meal times. Whether reheating leftovers or cooking a new recipe, the Sharp R-2397 sets itself apart as a reliable kitchen companion.
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