Sharp R-409js User manual

R-409JS

In the interest of user-safety the oven should be restored to its original condition and only parts identical to those specified

should be used.

WARNING TO SERVICE PERSONNEL: Microwave ovens contain circuitry capable of producing very high voltage and

current, contact with following parts may result in a severe, possibly fatal, electrical shock. (High Voltage Capacitor,

High Voltage Power Transformer, Magnetron, High Voltage Rectifier Assembly, High Voltage Harness etc..)

TABLE OF CONTENTS

Page

PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICING TO

AVOID POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY .................. INSIDE FRONT COVER

BEFORE SERVICING ..................................................................................................... INSIDE FRONT COVER

WARNING TO SERVICE PERSONNEL .............................................................................................................. 1

MICROWAVE MEASUREMENT PROCEDURE .................................................................................................. 2

FOREWORD AND WARNING ............................................................................................................................. 3

PRODUCT SPECIFICATIONS ............................................................................................................................. 4

GENERAL INFORMATION ...................................................................................................................................4

KEY UNIT TEST....................................................................................................................................................6

TOUCH CONTROL PANEL ASSY..................................................................................................................7

CPU UNIT CIRCUIT ............................................................................................................................................. 12

PARTS LIST ........................................................................................................................................................ 13

PACKING AND ACCESSORIES ......................................................................................................................... 17

S44M236R409JE

R-409JS

MICROWAVE OVEN

MODEL

SUPPLEMENTAL SERVICE MANUAL

SHARP ELECTRONCS CORPORATION

This document has been published to be used for after

sales service only.

The contents are subject to change without notice.

Service Headquarters: Sharp Plaza, Mahwah, New Jersey, 07430-2135

R-409JS

This is a supplemental Service Manual for Microwave Oven model R-409JS. This model is quite similar to the base models

R408JK/JW; (S24M231R408JE).

This supplemental manual must be used in conjunction with the base model service manual for complete operation,

service, safety and replacement parts information.

R-409JS

PRECAUTIONS TO BE OBSERVED BEFORE AND

DURING SERVICING TO AVOID POSSIBLE

EXPOSURE TO EXCESSIVE MICROWAVE

ENERGY

(a) Do not operate or allow the oven to be operated with the door open.

(b) Make the following safety checks on all ovens to be serviced before activating the magnetron or other

microwave source, and make repairs as necessary: (1) interlock operation, (2) proper door closing, (3)

seal and sealing surfaces (arcing, wear, and other damage), (4) damage to or loosening of hinges and

latches, (5) evidence of dropping or abuse.

compartments, check the magnetron, wave guide or transmission line, and cavity for proper alignment,

integrity, and connections.

(d) Any defective or misadjusted components in the interlock, monitor, door seal, and microwave generation

and transmission systems shall be repaired, replaced, or adjusted by procedures described in this

manual before the oven is released to the owner.

(e) A microwave leakage check to verify compliance with the Federal Performance Standard should be

performed on each oven prior to release to the owner.

BEFORE SERVICING

Before servicing an operative unit, perform a microwave emission check as per the

Microwave Measurement Procedure outlined in this service manual.

If microwave emissions level is in excess of the specified limit, contact SHARP

ELECTRONICS CORPORATION immediately @1-800-237-4277.

If the unit operates with the door open, service person should 1) tell the user

not to operate the oven and 2) contact SHARP ELECTRONICS CORPORATION and Food and

Drug Administration's Center for Devices and Radiological Health immediately.

Service personnel should inform SHARP ELECTRONICS CORPORATION of any certified unit

found with emissions in excess of 4mW/cm2. The owner of the unit should be instructed

not to use the unit until the oven has been brought into compliance.

R-409JS

WARNING TO SERVICE PERSONNEL

Microwave ovens contain circuitry capable of pro-

ducing very high voltage and current, contact with

following parts

may result in a severe, possibly

fatal, electrical shock.

(Example)

High Voltage Capacitor, High Voltage Power Trans-

former, Magnetron, High Voltage Rectifier Assem-

bly, High Voltage Harness etc..

Read the Service Manual carefully and follow all

instructions.

Before Servicing

1. Disconnect the power supply cord , and then

remove outer case.

2. Open the door and block it open.

3. Discharge high voltage capacitor.

WARNING:RISK OF ELECTRIC SHOCK.

DISCHARGE THE HIGH-VOLTAGE

CAPACITOR BEFORE SERVICING.

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 the connecting lead of the high-

voltage rectifier) against the chassis with the use of an

insulated screwdriver.

Whenever troubleshooting is performed the power supply

must be disconnected. It may, in some cases, be necessary

to connect the power supply after the outer case has been

removed, in this event:

1. Disconnect the power supply cord, and then remove

outer case.

2. Open the door and block it open.

3. Discharge high voltage capacitor.

4. Disconnect the leads to the primary of the power

transformer.

5. Ensure that the leads remain isolated from other

components and oven chassis by using insulation tape.

6. After that procedure, reconnect the power supply cord.

When the testing is completed,

1. Disconnect the power supply cord, and then remove

outer case.

2. Open the door and block it open.

3. Discharge high voltage capacitor.

4. Reconnect the leads to the primary of the power

transformer.

5. Reinstall the outer case (cabinet).

6. Reconnect the power supply cord after the outer case is

installed.

7. Run the oven and check all functions.

After repairing

1. Reconnect all leads removed from components during

testing.

2. Reinstall the outer case (cabinet).

3. Reconnect the power supply cord after the outer case is

installed.

4. Run the oven and check all functions.

Microwave ovens should not be operated 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 power to HIGH and set the microwave timer for two

(2) minutes. When the two minutes has elapsed (timer at

zero) carefully check that the water is now hot. If the water

remains cold carry out Before Servicing procedure 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 a microwave leakage test should be carried out.

Don't Touch !

Danger High Voltage

R-409JS

MICROWAVE MEASUREMENT PROCEDURE

A. Requirements:

1) Microwave leakage limit (Power density limit): The power density of microwave radiation emitted by a microwave oven

should not exceed 1mW/cm2at any point 5cm or more from the external surface of the oven, measured prior to acquisition

by a purchaser, and thereafter (through the useful life of the oven), 5 mW/cm2at any point 5cm or more from the external

surface of the oven.

2) Safety interlock switches:

Primary interlock relay switch shall prevent microwave radiation emission in excess of the requirement as above

mentioned. Secondary interlock relay and door sensing switch shall prevent microwave radiation emission in excess of

5 mW/cm2 at any point 5cm or more from the external surface of the oven.

B. Preparation for testing:

Before beginning the actual measurement of leakage, proceed as follows:

1) Make sure that the actual instrument is operating normally as specified in its instruction booklet.

Important:

Survey instruments that comply with the requirement for instrumentation as prescribed by the performance standard for

microwave ovens, 21 CFR 1030.10(c)(3)(i), must be used for testing.

2) Place the oven tray in the oven cavity.

3) Place the load of 275±15 ml (9.8 oz) of tap water initially at 20±5O

C (68OF) in the center of the oven cavity.

The water container shall be a low form of 600 ml (20 oz) beaker with an inside diameter of approx. 8.5 cm (3-1/2 in.) and

made of an electrically nonconductive material such as glass or plastic.

The placing of this standard load in the oven is important not only to protect the oven, but also to insure that any leakage

is measured accurately.

4) Set the cooking control on Full Power Cooking Mode.

5) Close the door and select a cook cycle of several minutes. If the water begins to boil before the survey is completed, replace

it with 275 ml of cool water.

C. Leakage test:

Closed-door leakage test (microwave measurement):

1) Grasp the probe of the survey instrument and hold it perpendicular to the gap between the door and the body of the oven.

2) Move the probe slowly, not faster than 1 in./sec. (2.5 cm/sec.) along the gap, watching for the maximum indication on the

meter.

3) Check for leakage at the door screen, sheet metal seams and other accessible positions where the continuity of the metal

has been breached (eg., around the switches, indicator, and vents).

While testing for leakage around the door, pull the door away from the front of the oven as far as is permitted by the closed

latch assembly.

4) Measure carefully at the point of highest leakage and make sure that the highest leakage is no greater than 4mW/cm2, and

that the primary interlock switch/secondary interlock relay does turn the oven OFF before any door movement.

NOTE: After servicing, record data on service invoice and microwave leakage report.

R-409JS

SHARP ELECTRONICS CORPORATION

SHARP PLAZA, MAHWAH,

NEW JERSEY 07430-2135

SERVICE MANUAL

MICROWAVE OVEN

R-409JS

FOREWORD

This supplemental Manual has been prepared to provide Sharp Electronics

Corp. Service Personnel with Operation and Service Information for the

SHARP MICROWAVE OVEN, R-409JS.

Model R-409JS, is quite similar to base models R-408JK/JW

(Ref.# S24M231R408JE).

It is recommended that service personnel carefully study the entire text of

this manual so that they will be qualified to render satisfactory customer

service.

Check the interlock switches and the door seal carefully. Special attention

should be given to avoid electrical shock and microwave radiation hazard.

WARNING

Never operate the oven until the following points are ensured:

(A) The door is tightly closed.

(B) The door brackets and hinges are not defective.

(D) The door is not deformed or warped.

(E) There is no other visible damage with the oven.

Servicing and repair work must be carried out only by trained service

personnel.

DANGER

Certain initial parts are intentionally not grounded and present

a risk of electrical shock only during servicing. Service person-

nel - Do not contact the following parts while the appliance is

energized;

High Voltage Capacitor, Power Transformer, Magnetron, High

Voltage Rectifier Assembly, High Voltage Harness;

If provided, Vent Hood, Fan assembly, Cooling Fan Motor.

All the parts marked “*” on parts list are used at voltages more than

250V.

Removal of the outer wrap gives access to voltage above 250V.

All the parts marked “∆” on parts list may cause undue microwave

exposure, by themselves, or when they are damaged, loosened or

removed.

PRODUCT DESCRIPTION

GENERAL INFORMATION

WIRING DIAGRAM

PARTS LIST

R-409JS

GENERAL INFORMATION

GROUNDING INSTRUCTIONS

This oven is equipped with a three prong grounding plug. It must be plugged into a wall receptacle that is properly installed

and grounded in accordance with the National Electrical Code and local codes and ordinances.

In the event of an electrical short circuit, grounding reduces the risk of electric shock by providing an escape wire for the electric

current.

WARNING: Improper use of the grounding plug can result in a risk of electric shock.

Electrical Requirements

The electrical requirements are a 120 volt 60 Hz, AC only,

15 or 20 amp. fused electrical supply. It is recommended that a separate circuit serving only this appliance be provided. When

installing this appliance, observe all applicable codes and ordinances.

A short power-supply cord is provided to reduce risks of becoming entangled in or tripping over a longer cord.

Where a two-pronged wall-receptacle is encountered, it is the personal responsibility and obligation of the customer to contact

SPECIFICATION

ITEM DESCRIPTION

PowerRequirements 120 Volts

14.0 Amperes, 1600 watts

60 Hertz

Single phase, 3 wire grounded

Power Output 1100 watts (IEC TEST PROCEDURE)

Operating frequency of 2450MHz

Case Dimensions Width 21-21/32"

Height 12-3/8"

Depth 18-7/16"

Cooking Cavity Dimensions Width 15-23/32

Height 9-21/32"

1.6 Cubic Feet Depth 17-7/8"

Control Complement Touch Control System

Clock ( 1:00 - 12:59 )

Timer (0 - 99 min. 99 seconds)

Microwave Power for Variable Cooking

Repetition Rate;

P-HI .................................................. Full power throughout the cooking time

P-90 .................................................................... approx. 90% of Full Power

P-80 .................................................................... approx. 80% of Full Power

P-70 .................................................................... approx. 70% of Full Power

P-60 .................................................................... approx. 60% of Full Power

P-50 .................................................................... approx. 50% of Full Power

P-40 .................................................................... approx. 40% of Full Power

P-30 .................................................................... approx. 30% of Full Power

P-20 .................................................................... approx. 20% of Full Power

P-10 .................................................................... approx. 10% of Full Power

P-0 ...................................................... No power throughout the cooking time

START, MINUTE PLUS pad, Cook pads, Defrost pads, Reheat pads, Number

selection pads, Power Level pad, Timer/Clock pad, Stop/Clear pad.

Oven Cavity Light Yes

Safety Standard UL Listed FCC Authorized

DHHS Rules, CFR, Title 21, Chapter 1, Subchapter J

R-409JS

a qualified electrician and have it replaced with a properly grounded

three-pronged wall receptacle or have a grounding adapter properly

grounded and polarized. If the extension cord must be used, it should be

a 3-wire, 15 amp. or higher rated cord. Do not drape over a countertop

or table where it can be pulled on by children or tripped over accidentally.

CAUTION: DO NOT UNDER ANY CIRCUMSTANCES CUT OR RE-

MOVE THE ROUND GROUNDING PRONG FROM THIS

PLUG.

OVEN DIAGRAM

1. One touch door open button.

Push to open door.

2. Door latches.

The oven will not operate unless the

door is securely closed.

3. Removable turntable support.

4. Removable turntable.

The turntable will rotate clockwise or

counterclockwise.

5. Oven lamp.

It will light when oven is operating or

door is opened.

6. Oven door with see-through window.

7. Ventilation openings. (Rear)

8. Auto-Touch control panel.

9. Time display: Digital display, 99

minutes 99 seconds.

10. Wave guide cover.

11. Power supply cord

TOUCH CONTROL PANEL

3-Pronged

Plug

Grounded

Receptacle Box

Grounding Pin

3-Pronged Receptacle

NOTE:

The directed features are disa-

bled after one minute when the

oven is not in use. These features

are automatically enabled when

the door is opened and closed or

the STOP/ CLEAR pad is pressed.

R-409JS

210

R-409JS

TEST PROCEDURES

PROCEDURE

LETTER COMPONENT TEST

1. Disconnect the power supply cord, and then remove outer case.

2. Open the door and block it open.

3. Discharge high voltage capacitor.

4. Using an ohmmeter and referring to the key unit matrix indicated on the control unit circuit, check the

circuit between the pins of the key unit that correspond to the STOP/CLEAR pad. When the pad is

pressed, the ohmmeter should indicate short circuit. When the pad is released, the ohmmeter should

indicate open circuit. If incorrect readings are obtained, the key unit is faulty and must be replaced.

About the other pads, the above method may be used.

5. Reconnect all leads removed from components during testing.

6. Re-install the outer case (cabinet).

7. Reconnect the power supply cord after the outer case is installed.

8. Run the oven and check all functions.

NO. G1

NO. G13

Key unit ribbon cable

Key unit (Membrane Switch) front view

JKEY UNIT TEST

G10G11G12G13 G9

G8 G7 G6 G5 G4 G3 G2 G1

TIMER

CLOCK

POPCORN

MINUTE PLUS

START

STOP

CLEAR

REHEAT

DEFROST

COOK

POWER

LEVEL

R-409JS

3) Power Source Circuit

This circuit generates voltages 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

VSS -5V LSI(IC1)

4) Relay Circuit

A 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.

8) Back Light Circuit

A circuit to drive the back light (Light emitting diodes LD1-

LD4).

TOUCH CONTROL PANEL ASSEMBLY

OUTLINE OF TOUCH CONTROL PANEL

The touch control section consists of the following units.

(1) Key Unit

(2) Control Unit (The Control Unit consists of Power Unit and

LSI Unit).

The principal functions of these units and the signals commu-

nicated among them 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 P20-P27.

When a key pad is touched, a signal is completed through the

key unit and passed back to the LSI through P70, P71, P41,

P45, P47 and AN3 to perform the function that was re-

quested.

Control Unit

Control unit consists of LSI, reset circuit, indicator circuit,

power source circuit, relay circuit, buzzer circuit, synchroniz-

ing signal circuit and back light circuit.

1) Reset Circuit

This circuit generates a signal which resets the LSI to the

initial state when power is supplied.

2) Indicator Circuit

This circuit consists of 22 segments and 3 common

electrodes using a Liquid Crystal Display.

R-409JS

1-2

VL2-VL1

IN Power source voltage input terminal.

Standard voltage for LCD.

3-6 AN7-AN4 IN Terminal to change cooking input according to the Model.

By using the A/D converter contained in the LSI, DC voltage in accordance with the Model

in operation is applied to set up its cooking constant.

7 AN3 IN Signal coming from touch key.

When either G13 line on key matrix is touched, a corresponding signal out of P20 - P27

will be input into AN3. When no key is touched, the signal is held at “H” level.

8 AN2 IN To input signal which communicates the door open/close information to LSI.

Door close "H" level signal (0V). Door Open "L" level (-5V).

9 AN1 IN Terminal not used.

10 AN0 IN Terminal not used.

11-13 P57-P55 OUT Terminal not used.

14 CNTR0 OUT Signal to sound buzzer (2.0 kHz).

A: key touch sound.

B: Completion sound.

15 P53 OUT Terminal not used.

16 P52 OUT Oven lamp, fan motor and turntable motor driving signal

To turn on and off shut off relay (RY1). The

square waveform voltage is delivered to the

RY1 driving circuit and RY2 control circuit.

17 P51 OUT Terminal not used.

18 P50 OUT Magnetron high-voltage circuit driving signal.

To turn on and off the cook relay (RY2). The

signals holds “L” level during microwave cook-

ing and “H” level while not cooking. In other

cooking modes (variable cooking) the signal

turns to “H” level and “L” level in repetition

according to the power level.

19 P47 IN Signal similar to AN3.

When either G13 line on key matrix is touched, a corresponding signal will be input into

P46.

20 P46 OUT Terminal not used.

21 P45 IN Signal similar to AN3.

When either G12 line on key matrix is touched, a corresponding signal will be input into

P45.

22-23 P44-P43 OUT Terminal not used.

24 INT0 IN Signal synchronized with commercial power source frequency.

This is the basic timing for time processing of LSI.

DESCRIPTION OF LSI

LSI

The I/O signal of the LSI is detailed in the following table.

Pin No. Signal I/O Description

0.1 sec.

2.0 sec.

H : GN

L : -5V

H : GN

L : -5V

16.7 msec.

During cooking

H : GND

L : -5V

Maximum

output

70% of maximum

output

H : GND

L : -5V

H : GND

L : -5V

OFF

OFF OFF

24 sec.

8 sec.

16.7 msec.

H : GN

L : -5V

R-409JS

25 P41 IN Signal similar to AN3.

When either G11 line on key matrix is touched, a corresponding signal will be input into

P41.

26 P40 IN Connected to GND through the pull-down resistor.

27 RESET IN Auto clear terminal.

Signal is input to reset the LSI to the initial state when power is applied.

28 P71 IN Signal similar to AN3.

When either G10 line on key matrix is touched, a corresponding signal will be input into

P71.

29 P70 IN Signal similar to ANI3.

When either G9 line on key matrix is touched, a corresponding signal will be input into P70.

30 XIN IN Internal clock oscillation frequency control input setting.

The internal clock frequency is set by inserting the ceramic filter oscillation circuit with

respect to XOUT terminal.

31 XOUT OUT Internal clock oscillation output.

Output to control oscillation input to XIN.

32 VSS IN Power source voltage : -5.0V.

The power source voltage to the drive LSI is input to VSS terminal.

33 P27 OUT Key strobe signal.