Sharp R-2397 Control Unit, Power Supply Circuit, ACL Circuit, Clock Circuit, IC1 Main Processor

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R-2397

TOUCH CONTROL PANEL ASSEMBLY

OUTLINE OF TOUCH CONTROL PANEL

The touch control section consists of the following units as shown in the touch control panel circuit.

(1)Control Unit

(2)Key Unit

The principal functions of these units and the signals commu- nicated among them are explained below.

1.Control Unit

Signal of key touch and oven function control are all processed by one microcomputer.

1)Power Supply Circuit

This circuit changes output voltage at the secondary side of the low voltage (T1) transformer to volatges required at each part by full wave rectifying circuit, constant voltage circuit, etc..

2)ACL Circuit

This AC voltage is then half wave rectified by D61/D62 and smoothed (filtered) by C61/C62.

This AC voltage is the input to the IN3 and IN5 ports of IC1, which determines if there is a magnetron / high voltage problem.

HIGH VOLTAGE TRANSFORMER

 

 

 

 

HIGH VOLTAGE CIRCUIT

 

 

 

 

MAIN BODY SIDE

CT1 or CT2

 

 

 

T/C SIDE

 

 

 

 

RY3 or RY4

 

 

 

R61 or

R65 or

 

 

R62

R66

 

 

 

 

 

 

C61 or C62

 

 

 

 

IC1

D61 or

R63 or

D63 or

IN3 or

IN5 PORT

D62

R64

D64

 

 

 

This is an Auto-clear Circuit, i.e., a reset circuit, which enables IC1 to be activated from initial state.

Vc

3)Power SYNC Signal Generating Circuit

This is a circuit for generating power SYNC signal by virtue of the secondary side output of transformer T1. This signal is used for a basic frequency to time process- ing and so on.

4)Clock Circuit

This is a circuit for controlling clock frequency required for operating IC1.

5)IC1 (Main Processor)

This is a one-chip microcomputer, responsible for con- trolling the entire control unit.

6)IC2 (Memory Processor)

This is a memory IC, responsible for memory function.

7)Display Circuit

This is a circuit for driving display tubes by IC1 output.

8)Key Input Circuit

This is a circuit for transmitting key input information to IC1.

9)Sound-body Driving Circuit

This is a circuit for driving sound body by IC1 output.

10) Relay Driving Circuit

This is a circuit for driving output relay by IC1 output.

11) Stop Switch Circuit

This is a circuit for driving IC1 to detect door opening/ closing.

12) Exhaust Air Temperature Detecting Circuit

This is a circuit for transmitting output change of thermistor (Exhaust Air Temperature Sensor) to IC1.

13) High Voltage Monitoring Circuit.

This circuit detects problems in the magnetron / high voltage circuit by sensing a variation in the current flowing through the primary winding of the high voltage transformer.

During heating, the primary current of the high voltage transformers also flows through the primary winding of the current transformers CT1 and CT2. This causes a current to be induced in the secondary windings of CT1/ CT2 and results in an AC voltage which is determined by R61/R62.

Figure T-1. High Voltage Monitoring Circuit

14)Magnetron Temperature Circuit. (Detect Noload or Fan Lock)

This is a circuit for transmitting output change of thermistor (Magnetron Temperature Sensor) to IC1.

15) Intake Air Temperature Detecting Circuit.

This is a circuit for transmitting output change of thermistor (Intake Air Sensor) to IC1.

2. Key Unit

The key unit is composed of a matrix circuit in which when a key it touched, one of signals P11, P12, P15, P16 and P17 generated by the LSI, is passed through the key and returned to the LSI as one of signals R0--R3. This model has 20 Memory pads. When the oven is shipped, Memory pad 1 to 10 are set as follows: fig.1.

Memory No.

Cook Time

Output Power

1

5sec.

100%

2

10sec.

100%

3

20sec.

100%

4

30sec.

100%

5

40sec.

100%

6

50sec.

100%

7

1min.

100%

8

1min.15sec.

100%

9

1min.30sec.

100%

10

2min.

100%

 

 

 

 

(fig. 1)

 

This model has a double quantity pad. When the oven is shipped, Magnification "1.8" is preset in the double quantity pad. This model has an defrost pad. When the oven is shipped, defrost is set as follows: fig.2.

 

 

1 STAGE

POWER

 

10%

OVEN ON/OFF

 

ON

 

 

 

 

(fig. 2)

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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 TestMin Cx ± 20% Cy ± 20% 5mH Touch Control Panel Assembly TestKEY Unit Test 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 RemovalRe-install Power Supply Cord ReplacementAfter adjustment, make sure of the following 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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