Sharp R-203CW User Manual

17
R-203CW
The touch control section consists of the following units as
shown in the touch control panel circuit.
(1) Key Unit
(2) Control Unit
The principal functions of these units and their related
signals are explained below.
Key Unit
The key unit is composed of a matrix, signals generated in
the LSI are sent to the key unit through R81, R82, R83, R90,
R91 and R92.
When a key pad is touched, a signal is completed through
the key unit and passed back to the LSI through R60, R61,
R62, R63 to perform the function that was requested.
Control Unit
Control unit consists of LSI, ACL circuit, indicator circuit,
power source circuit, relay circuit, buzzer circuit and syn-
chronizing signal circuit.
1) ACL
This circuit generates a signal which resets the LSI to the
initial state when power is supplied.
2) Indicator Circuit
This circuit consists of 4-digits, 12-segments and 3-
common electrodes using a Liquid Crystal Display.
TOUCH CONTROL PANEL ASSEMBLY
OUTLINE OF TOUCH CONTROL PANEL
3) Power Source Circuit
This circuit generates voltage necessary in the control
unit from the AC line voltage. In addition, the synchronizing
signal is available in order to compose a basic standard
time in the clock circuit.
Symbol Voltage Application
VC -5V LSI(IC1)
4) Relay Circuit
To drive the magnetron, fan motor, turntable motor and
light the oven lamp.
5) Buzzer Circuit
The buzzer is responsive to signals from the LSI to emit
audible sounds (key touch sound and completion sound).
6) Synchronizing Signal Circuit
The power source synchronizing signal is available in
order to compose a basic standard time in the clock
circuit. It accompanies a very small error because it
works on commercial frequency.
7) Door Sensing Switch
A switch to "tell" the LSI if the door is open or closed.

Sharp R-203CW Specifications

General

Brand	Sharp
Model	R-203CW
Category	Microwave Oven
Language	English

Summary

Safety Precautions for Servicing

Before Servicing

Procedures to follow before starting any servicing.

Service Personnel Warnings

Pre-Service Procedures

Steps to disconnect power and discharge capacitor.

Post-Test Procedures

Steps after completing tests.

Post-Repair Procedures

Steps after completing repairs.

Microwave Measurement Procedure

Test Requirements

Specifies limits for microwave leakage.

Test Preparation

Steps for preparing the oven and equipment.

Leakage Test Steps

Detailed steps for performing the leakage test.

Product Overview

Specifications

Lists technical specifications of the microwave oven.

General Information

Grounding Instructions

Explains proper grounding procedures for safety.

Operation Details

Operating Sequence

Details the sequence of operation for the oven.

Variable Power Cooking

Explains variable power cooking levels.

Schematics and Component Functions

Oven Schematics

Electrical diagrams for oven operation states.

Component Descriptions

Explains functions of key components.

Troubleshooting Guide

Problem Diagnosis

Table linking problems to potential causes/parts.

Component Test Procedures

Magnetron Assembly Test

Procedure to test the magnetron.

Microwave Output Power Test

Procedure to measure microwave power output.

Power Transformer Test

Procedure to test the power transformer.

High Voltage Rectifier Test

Procedure to test the HV rectifier.

High Voltage Capacitor Test

Procedure to test the HV capacitor.

Magnetron Thermal Cut-Out Test

Procedure to test the magnetron thermal cut-out.

Secondary Interlock Switch Test

Procedure to test the secondary interlock switch.

Door Sensing Switch Test

Procedure to test the door sensing switch.

Primary Interlock Relay Test

Procedure to test the primary interlock relay.

Monitor Switch Test

Procedure to test the monitor switch.

Blown C/T Fuse Test

Procedure to test for a blown C/T fuse.

Touch Control Panel Testing

Key Unit Test

Procedure to test the key unit of the control panel.

Control Unit Diagnosis

Symptoms indicating a defective control unit.

Specific Component Tests

Relay Test

Checks the operational voltage and function of relays.

Compu Defrost Test

Checks the operation of the Compu Defrost function.

Printed Wiring Board Test

Foil Pattern Test

Inspects and repairs foil patterns on the PWB.

Control Panel Assembly Details

Key Unit Function

Explains the function of the key unit.

Control Unit Functions

Details functions of the control unit components.

LSI Description

LSI Signal Details

Lists and describes LSI pin signals and functions.

Servicing Guidelines

Component Handling Precautions

Guidelines for safely handling electronic components.

Touch Control Panel Servicing

Procedures for servicing the touch control panel.

Component Replacement & Adjustment

Outer Case Removal

Steps to remove the outer case of the oven.

Magnetron Removal

Procedure to remove the magnetron.

High Voltage Components Removal

Procedure to remove HV capacitor and rectifier.

Power Transformer Removal

Procedure to remove the power transformer.

Oven Lamp Removal

Procedure to remove the oven lamp and socket.

Connector Removal

Procedure to remove positive lock connectors.

Control Panel Removal

Procedure to remove the control panel assembly.

Turntable Motor Removal

Procedure to remove the turntable motor.

Cooling Fan Motor Removal

Procedure to remove the cooling fan motor.

Switch Removal

Procedure to remove door safety switches.

Switch Adjustment

How to adjust door safety switches.

Door Replacement

Procedure for replacing the oven door.

Door Disassembly

Steps to disassemble the oven door.

Sealer Film Installation

Procedure for installing the door sealer film.

Parts List

Electric Parts

Lists electrical components and their part numbers.

Cabinet Parts

Lists cabinet components and their part numbers.

Control Panel Parts

Lists control panel components and their part numbers.

Oven Parts

Lists oven cavity and related parts.

Door Parts

Lists parts specific to the oven door.

Miscellaneous Parts

Lists miscellaneous items like harnesses and manuals.

Screws and Washers

Lists various screws and washers used in the unit.

Packing and Accessories

Included Accessories

Lists items included with the microwave oven.